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Background: The long-term prognosis of jumper's knee and whether structural changes in the patellar tendon persist is unknown., Purpose: To investigate whether limitations in knee function and structural changes persisted beyond the athletic career of young elite volleyball players., Study Design: Cohort study; Level of evidence, 2., Methods: Volleyball players (mean ± SD age, 18 ± 0.8 years) enrolled in 2006-2011 in a prospective cohort study were invited in 2020-2022 to a follow-up study. Participants rated their knee function with the Victorian Institute of Sport Assessment-Patellar Tendon (VISA-P) score (baseline and follow-up) and the International Knee Documentation Committee (IKDC) score (follow-up) and reported if jumper's knee had influenced their decision to retire from sport. Tendon thickness and structural changes were assessed with ultrasound (baseline) and magnetic resonance imaging (MRI) (follow-up) of both patellar tendons., Results: We included 138 of 143 former athletes (97%) 11.4 ± 1.6 years after their baseline examination. At baseline, 37 persons (52 knees) had developed jumper's knee. At follow-up, participants reported lower knee function scores in knees diagnosed with jumper's knee at baseline than healthy knees (VISA-P scores: jumper's knee, 81 [95% CI, 70-92]; healthy, 90 [95% CI, 86-94]; P < .001; IKDC scores: jumper's knee, 82 [95% CI, 75-89]; healthy, 92 [95% CI, 91-95]; P < .001). Jumper's knee problems directly caused 7 of the 37 athletes (19%) with jumper's knee at baseline to retire from competitive volleyball. Of the 138 players included, 97 (70%) completed a bilateral MRI examination (194 knees). At follow-up, 38 of the 54 abnormal tendons (70%) had no structural changes ( P < .001 vs baseline) while 22 of the 140 normal tendons (16%) had developed structural changes. Clinical symptoms were not correlated with tendon structure at follow-up (VISA-P scores for normal tendons: 85 [95% CI, 73-87]; abnormal: 89 [95% CI, 85-92]; P = .48)., Conclusion: Jumper's knee is not a self-limiting condition; volleyball players who had developed jumper's knee during adolescence reported persistent reductions in knee function 11 years later, leading one-fifth to retire from competitive volleyball. Although approximately 70% of tendons with structural changes at baseline were normal at follow-up, there was no clear relationship between structure and function., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This study was made possible through a grant from the International Olympic Committee Medical Research Fund. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Rotator cuff repair augmentation using biological materials has become popular in clinical practice to reduce the high retear rates associated with traditional repair techniques. Tissue engineering approaches, such as engineered tendon-fibrocartilage-bone composite (TFBC), have shown promise in enhancing the biological healing of rotator cuff tears in animals. However, previous studies have provided limited long-term data on TFBC repair outcomes. The effect of mechanical stimulation on TFBC has not been explored extensively., Purpose: To evaluate functional outcomes after rotator cuff repair with engineered TFBC subjected to mechanical stimulation in a 6-month follow-up using a canine in vivo model., Study Design: Controlled laboratory study., Methods: A total of 40 canines with an acute infraspinatus (ISP) tendon transection model were randomly allocated to 4 groups (n =10): (1) unilateral ISP tendon undergoing suture repair only (control surgery); (2) augmentation with engineered TFBC alone (TFBC); (3) augmentation with engineered TFBC and bone marrow-derived stem cells (BMSCs) (TFBC+C); and (4) augmentation with engineered TFBC and BMSCs, as well as mechanical stimulation (TFBC+C+M). Outcome measures-including biomechanical evaluations such as failure strength, stiffness, failure mode, gross appearance, ISP tendon and muscle morphological assessment, and histological analysis-were performed 6 months after surgery., Results: As shown in the mechanical test, the TFBC+C+M group exhibited higher failure strength compared with other repair techniques. The most common failure mode was avulsion fracture in the TFBC+C+M group, but tendon-bone junction rupture was observed predominantly in different groups. Engineered TFBC with mechanical stimulation showed over 70% relative failure strength compared with normal ISP, and the other groups showed about 50% relative failure strength. Histological analysis revealed less fat infiltration and closer-to-normal muscle fiber structure in the mechanical stimulation group., Conclusion: This study provides evidence that mechanical stimulation of engineered TFBC promotes rotator cuff regeneration, thus supporting its potential for rotator cuff repair augmentation., Clinical Relevance: This study provides valuable evidence supporting the use of a novel tissue-engineered material (TFBC) in rotator cuff repair and paves the way for advancements in the field of rotator cuff regeneration., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by a grant from the National Institute of Health (AR73811). J.S.-S. has received consulting fees from Stryker, Acumed, and Exactech; royalties from Stryker, Elsevier, and OUP; and holds stocks in PSI, Orthobullets, and Precision OS. S.P.S. has received compensation for services other than consulting from Arthrex; support for education from Alpha Orthopedic Systems; and consulting fees from Acumed. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Large bone defect repair is a striking challenge in orthopedics. Currently, inorganic-organic composite scaffolds are considered as a promising approach to these bone regeneration. Silicon ions (Si 4+ ) are bioactive and beneficial to bone regeneration and Si 4+ -containing inorganic mesoporous silica (MS) can effectively load drugs for bone repair. To better control the release of drug, we prepared biodegradable MS/PLGA (MP) microspheres. MP loaded organic silk fibroin/carboxymethyl chitosan/sodium alginate (MP/SF/CMCS/SA) composite scaffolds were further constructed by genipin and Ca 2+ crosslinking. All MP/SF/CMCS/SA scaffolds had good swelling ability, degradation rate and high porosity. The incorporation of 1% MP significantly enhanced the compressive strength of composite scaffolds. Besides, MP loaded scaffold showed a sustained release of Si 4+ and Ca 2+ . Moreover, the release rate of rhodamine (a model drug) of MP/SF/CMCS/SA scaffolds was obviously lower than that of MP. When culturing with rat bone marrow mesenchymal stem cells, scaffolds with 1% MP displayed good proliferation, adhesion and enhanced osteogenic differentiation ability. Based on the results above, the addition of 1% MP in SF/CMCS/SA scaffolds is a prospective way for drug release in bone regeneration and is promising for further in vivo bone repair applications., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Morton neuroma is a common cause of forefoot pain and sensory disturbances, but it is difficult to identify on magnetic resonance imaging (MRI). The aim of this study was to verify the usefulness of a characteristic MRI finding (slug sign) for identifying Morton neuroma and to clarify the relationship between excised neuroma characteristics and preoperative MRI findings., Methods: Twenty-two web spaces were retrospectively assessed from the second and third intermetatarsal spaces of 11 feet of 10 patients (7 women and 3 men, aged average 59.5 years) who underwent surgical excision of Morton neuroma between 2017 and 2022. Asymptomatic web spaces were used as control. Neuromas with 2 branches of the plantar digital nerves on axial T1-weighted MRI (MRI-T1WI) were considered the slug sign. We investigated the preoperative presence of the slug sign in Morton neuroma and asymptomatic control web spaces. We also investigated the relationship between the maximum transverse diameter of the excised specimen and that estimated on coronal MRI-T1WI., Results: A total of 15 Morton neuromas were excised and assessed. The slug signs were present in 10 intermetatarsal spaces in 15 web spaces with Morton neuroma whereas the sign was found in 1 intermetatarsal space in 7 asymptomatic web spaces. The sensitivity and specificity for the slug sign to diagnose Morton neuroma was 66.7% and 85.7%, respectively. The positive and negative predictive values were 90.9% and 54.5%, respectively. The mean maximum transverse diameter of excised neuromas was 4.7 mm. The mean maximum transverse diameter of neuromas on coronal MRI-T1WI was 3.4 mm. A significant positive correlation was found between the maximum transverse diameters of excised specimens and diameters estimated on coronal MRI-T1WI ( r  = 0.799, P  < .001)., Conclusion: The slug sign may be a useful indicator of Morton neuroma on MRI to confirm nerve involvement after bifurcation., Level of Evidence: Level IV, retrospective series., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Disclosure forms for all authors are available online., (© The Author(s) 2024.)

Background: Quadriceps and hamstring strength deficits are related to the increased risk of reinjury after anterior cruciate ligament reconstruction (ACLR)., Hypothesis: Knee angle-specific quadriceps and hamstring strength differences would be observed in patients with ACLR 6 and 12 months after surgery., Study Design: Case-series., Level of Evidence: Level 4., Methods: A total of 23 postprimary unilateral ACLR patients followed-up at 6 and 12 months postoperatively and 25 controls were included. Isokinetic knee extension and flexion strength were evaluated at 60 deg/s from 20° to 90°. Statistical parametric mapping were performed to explore the angle-specific strength and the limb symmetry index (LSI)., Results: At 6 months postoperatively, the reconstructed leg demonstrated lower knee extension and flexion strength than the contralateral (20°-77°, 24°-90°) ( P < 0.01) and control legs (22°-90°, 40°-82°) ( P < 0.01). From 6 months to 12 months, knee extension (60°-90°) and flexion (20°-79°) strength improved in the reconstructed leg ( P < 0.05), while LSI remained unchanged ( P > 0.02). At 12 months, knee extension strength differences persisted in the reconstructed leg compared with the contralateral (20°-81°) and controls (25°-63°) ( P < 0.01). ACLR patients had lower LSI of knee extension strength at 6 (20°-59°) and 12 (24°-57°) months postoperatively than the controls ( P < 0.02)., Conclusion: The reconstructed leg exhibited differences in knee extension strength compared with the contralateral and control legs. Although bilateral knee extension strength increased from 6 to 12 months postoperatively, LSI did not show improvement during this period., Clinical Relevance: Quadriceps restoration was observed only in knee flexion angles greater than 60° compared with controls. Future studies should investigate whether knee extension strength, especially in lower flexion angles, can be enhanced through rehabilitation programs. Furthermore, assessing the impact of this improvement on long-term outcomes and reinjury risk in ACLR patients is warranted., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: Earlier statements suggested a negative impact of coronavirus disease 2019 (COVID-19) infection on sports performance and injury risk. With the COVID-19 pandemic under control and the dominance of a less-severe strain of the virus, there is a need to confirm whether these adverse effects still apply to the current situation., Hypothesis: Infected players would have a higher noncontact muscle injury incidence compared with noninfected counterparts., Study Design: Cohort observational study., Level of Evidence: Level 3., Methods: Seven teams (n = 147 players) competing in the Spanish professional women's football league (Liga F) were prospectively monitored during the 2021-2022 season. Data from noncontact injuries were recorded and classified following the latest consensus statement from the International Olympic Committee. COVID-19 was certified by the medical staff by regular polymerase chain reaction analysis., Results: Ninety-two players suffered at least 1 noncontact muscle injury during the season. Injury incidence during the season was similar in players with COVID-19 (n = 83) and players without infection (5.1 ± 6.7 versus 4.9 ± 10.0 injuries/1000 h of play, respectively; P = 0.90). Players with COVID-19 were not more likely to suffer noncontact injuries compared with those players without infection ( R 2 = 0.31). There was no effect of COVID-19 on the days of absence due to injury ( P = 0.31). There was no effect of COVID-19 on the days of absence due to injury ( R = 0.44) or in the classification of the severity of the injury ( 2 = 0.01; OR 95% CI = 1.00-1.01; P = 0.44) or in the classification of the severity of the injury ( P = 0.79)., Conclusion: COVID-19 has no significant effect on noncontact injury incidence and severity in professional female football players., Clinical Relevance: Currently, COVID-19 infection does not alter noncontact muscle injury risk in professional football and requires no further attention in terms of injury management. Usual return-to-play protocols apply to COVID-19 considering the particularities of each player since the severity of infection, period of inactivity, and effects on the player's health and performance., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: In adults with anterior cruciate ligament (ACL) tears, bone bruises on magnetic resonance imaging (MRI) scans provide insight into the underlying mechanism of injury. There is a paucity of literature that has investigated these relationships in children with ACL tears., Purpose: To examine and compare the number and location of bone bruises between contact and noncontact ACL tears in pediatric patients., Study Design: Cohort study; Level of evidence, 3., Methods: Boys ≤14 years and girls ≤12 years of age who underwent primary ACL reconstruction surgery between 2018 and 2022 were identified at 3 separate institutions. Eligibility criteria required detailed documentation of the mechanism of injury and MRI performed within 30 days of the initial ACL tear. Patients with congenital lower extremity abnormalities, concomitant fractures, injuries to the posterolateral corner and/or posterior cruciate ligament, previous ipsilateral knee injuries or surgeries, or closed physes evident on MRI scans were excluded. Patients were stratified into 2 groups based on a contact or noncontact mechanism of injury. Preoperative MRI scans were retrospectively reviewed for the presence of bone bruises in the coronal and sagittal planes using fat-suppressed T2-weighted images and a grid-based mapping technique of the tibiofemoral joint., Results: A total of 109 patients were included, with 76 (69.7%) patients sustaining noncontact injuries and 33 (30.3%) patients sustaining contact injuries. There were no significant differences between the contact and noncontact groups in terms of age (11.8 ± 2.0 vs 12.4 ± 1.3 years; P = .12), male sex (90.9% vs 88.2%; P > .99), time from initial injury to MRI (10.3 ± 8.1 vs 10.4 ± 8.9 days; P = .84), the presence of a concomitant medial meniscus tear (18.2% vs 14.5%; P = .62) or lateral meniscus tear (69.7% vs 52.6%; P = .097), and sport-related injuries (82.9% vs 81.8%; P = .89). No significant differences were observed in the frequency of combined lateral tibiofemoral (lateral femoral condyle + lateral tibial plateau) bone bruises (87.9% contact vs 78.9% noncontact; P = .41) or combined medial tibiofemoral (medial femoral condyle [MFC] + medial tibial plateau) bone bruises (54.5% contact vs 35.5% noncontact; P = .064). Patients with contact ACL tears were significantly more likely to have centrally located MFC bruising (odds ratio, 4.3; 95% CI, 1.6-11; P = .0038) and less likely to have bruising on the anterior aspect of the lateral tibial plateau (odds ratio, 0.27; 95% CI, 0.097-0.76; P = .013)., Conclusion: Children with contact ACL tears were 4 times more likely to present with centrally located MFC bone bruises on preoperative MRI scans compared with children who sustained noncontact ACL tears. Future studies should investigate the relationship between these bone bruise patterns and the potential risk of articular cartilage damage in pediatric patients with contact ACL tears., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: M.J.M. has received consulting fees from Arthrex and Smith + Nephew. R.F.L. has received consulting fees from Ossur and Smith + Nephew, royalties from Arthrex and Smith + Nephew, and research support from Arthrex and Linvatec. A.E.J. has received research support from Arthrex; support for education from Arthrex, Medwest, Polaris Technology Solutions, and Gotham Surgical Solutions & Devices; and hospitality payments from Abbott Laboratories. S.D.M. has received support for education from MedInc of Texas. P.D.F. has received consulting fees from WishBone Medical. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Arthroscopic anterior talofibular ligament repair (AATFLR) is a surgical strategy to treat chronic ankle instability (CAI) patients. This study identified risk factors that influenced the functional outcomes of AATFLR for CAI and developed prognostic nomogram for predicting functional outcomes in future AATFLR cases., Methods: Patients undergoing AATFLR from January 2016 to June 2022 with at least 10 months of follow-up were included in the study. The Karlsson Ankle Functional Score (KAFS) was evaluated preoperatively and at last follow-up visit. A total of 15 potential predictors including age, sex, body mass index, side affected, time from injury to surgery, sports-related injury, osteophyte, loose bodies, distal tibiofibular syndesmosis, ATFL avulsion fracture, Outerbridge classification of osteochondral lesions, postoperative immobilization method, ambulation time, walking time, and follow-up time, were recorded. We first used univariate binary logistic regression analysis to select the potential significant prognostic features, which were then subjected to the least absolute shrinkage and selection operator (LASSO) regression algorithm for final feature selection. A nomogram based on the regression model was developed to estimate the functional outcomes of patients. Models were validated internally using bootstrapping and externally by calculating their performance on a validation cohort., Results: Overall, 200 ankles fit inclusion criteria. Of these 200, a total of 185 (92.5%) ankles were eligible and divided into development (n = 121) and validation (n = 64) cohorts. Four predictors were ultimately included in the prognostic nomogram model: age, sex, sports-related injury, and postoperative immobilization method., Conclusion: We found in our cohort that the significant predictors of poorer functional outcomes of AATFLR were postoperative immobilization with lower-leg cast, female sex, non-sports-related ankle sprain, and increasing age. Prognostic nomograms were created., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Disclosure forms for all authors are available online.

Background: Massive irreparable rotator cuff tears (MIRCTs) are among the most challenging shoulder conditions to treat surgically. Supraspinatus tendon reconstruction (STR) is a recently introduced technique for MIRCTs based on fascia lata-muscle interface healing, which completely differs from the classic bridging technique with fascia lata-tendon interface healing. However, histological and biomechanical comparisons of the fascia-muscle and fascia-tendon interfaces have not been performed., Purpose: To investigate the histological and biomechanical healing of the fascia-bone interface and fascia-muscle interface after chronic MIRCTs in a rat model using different surgical methods., Study Design: Controlled laboratory study., Methods: The authors established a chronic MIRCT model in the right shoulder of rats and then repaired it using the STR or bridging repair technique. Evaluations were performed at 2, 4, 8, and 12 weeks, including histological, imaging, biomechanical, and functional analyses., Results: Both techniques resulted in good fascia-bone interface healing based on the histological results. The STR group had significantly more cartilage formation at 8 and 12 weeks and higher Modified Tendon Maturity Score after 12 weeks at the fascia-bone interface compared with the bridging repair group and formed the typical 4-layered structure. Collagen fibers in the fascia-muscle and fascia-tendon interfaces exhibited normal muscle-tendon interface characteristics at 12 weeks. However, the STR group had more improvement in fatty infiltration compared with the bridging repair group. The ultimate failure load and stiffness did not differ between the STR and bridging repair groups 4 weeks postoperatively in both the fascia-bone interface and supraspinatus muscle-fascia-bone integrity. Movement distance and grasp time were significantly longer in the STR group than in the bridging repair group at 12 weeks and attached the level in the normal control groups., Conclusion: These results suggest that the fascia-muscle interface from the STR technique is histologically and functionally better than the fascia-tendon interface. Moreover, this study provides a theoretical basis for the clinical use of the STR technique., Clinical Relevance: The fascia-muscle interface and fascia-tendon interface were the key points of the STR and bridging techniques, respectively. The fascia-muscle interface is histologically and functionally superior to the bridging technique, and the STR technique might be a better choice for the treatment of MIRCTs., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Bone marrow stimulation (BMS) is presently considered first-line surgical treatment for osteochondral lesions of the talus (OLTs); however, some patients still experience pain or dysfunction after surgery, and the reasons for success or failure remain somewhat unclear. This study aimed to investigate the effect of smoking on postoperative outcomes after arthroscopic BMS for OLTs., Methods: Consecutive patients with OLTs who underwent BMS between January 2017 and January 2020 were included. Smokers were defined as patients who actively consumed cigarettes before surgery and postoperatively, whereas nonsmokers were patients who never smoked. Visual analog scale (VAS), American Orthopaedic Foot & Ankle Society ankle hindfoot score (AOFAS), Karlsson-Peterson, and Tegner scores were assessed preoperatively and at follow-up. Additionally, a general linear model (GLM) was performed, followed by the interaction analysis to explore the potential influence of smoking., Results: The study enrolled 104 patients with a mean follow-up of 30.91 ± 7.03 months, including 28 smokers and 76 nonsmokers. There were no significant differences in patient age (35.2 ± 10.0 years vs 37.6 ± 9.7 years, P  = .282) or OLT area (63.7 ± 38.7 mm 2 vs 52.8 ± 37.0 mm 2 , P  = .782). Both univariate analysis and GLM revealed that smoking was associated with worse postoperative pain levels, Karlsson-Peterson, and AOFAS scores ( P  < .05). The interaction analysis showed a significant interaction between smoking and OLT area for postoperative Karlsson-Peterson scores (general ankle function) ( P  = .031). Simple main effects analysis revealed that the negative effect of smoking on Tegner score significantly increased among patients >32 years old or with OLT area>50 mm 2 ( P  < .05)., Conclusion: Smoking was associated with worse clinical outcomes following BMS of OLTs. As the size of OLTs increased, the difference in general ankle function between smokers and nonsmokers also increased. Furthermore, smokers who were older than 32 years or had larger OLTs were less likely to resume participation in high-level activities., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Dong Jiang, MD, reports grants from Capital Health Research and Development of Special (2022-2Z-40913), from Clinical Cohort Construction Program of Peking University Third Hospital (BYSYDL2022016), during the conduct of the study. Disclosure forms for all authors are available online.

Background: Cam morphology develops during skeletal growth, but its influence on cartilage and the labrum in high-impact athletes later in life is unknown., Purpose: To (1) explore the association between the presence and duration of cam morphology during adolescence and the cartilage and labral status 7 to 12 years later and (2) report the prevalence of cartilage loss and labral damage in a population of young male athletes (<32 years old) who played professional soccer during skeletal growth., Study Design: Cohort study (Prognosis); Level of evidence, 2., Methods: A total of 89 healthy male academy soccer players from the Dutch soccer club Feyenoord (aged 12-19 years) were included at baseline. At baseline and 2.5- and 5-year follow-ups, standardized supine anteroposterior pelvis and frog-leg lateral radiographs of each hip were obtained. At 12-year follow-up, magnetic resonance imaging of both hips was performed. Cam morphology was defined by a validated alpha angle ≥60° on radiographs at baseline or 2.5- or 5-year follow-up when the growth plates were closed. Hips with the presence of cam morphology at baseline or at 2.5-year follow-up were classified as having a "longer duration" of cam morphology. Hips with cam morphology only present since 5-year follow-up were classified as having a "shorter duration" of cam morphology. At 12-year follow-up, cartilage loss and labral abnormalities were assessed semiquantitatively. Associations were estimated using logistic regression, adjusted for age and body mass index., Results: Overall, 35 patients (70 hips) with a mean age of 28.0 ± 2.0 years and mean body mass index of 24.1 ± 1.8 participated at 12-year follow-up. Cam morphology was present in 56 of 70 hips (80%). The prevalence of cartilage loss was 52% in hips with cam morphology and 21% in hips without cam morphology (adjusted odds ratio, 4.52 [95% CI, 1.16-17.61]; P = .03). A labral abnormality was present in 77% of hips with cam morphology and in 64% of hips without cam morphology (adjusted odds ratio, 1.99 [95% CI, 0.59-6.73]; P = .27). The duration of cam morphology did not influence these associations., Conclusion: The development of cam morphology during skeletal growth was associated with future magnetic resonance imaging findings consistent with cartilage loss in young adults but not with labral abnormalities., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: The Anna Foundation (Anna Fonds) and the Dutch Orthopaedic Research and Education Foundation provided financial support for this study. D.E. has received a personal educational grant (€2200) from Zimmer Biomet. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: The self-repair ability after meniscal tears is poor, leading to the development of posttraumatic osteoarthritis. Promoting the repair of meniscal injuries remains a great challenge, especially in the avascular region., Hypothesis: Local delivery of skeletal stem cell (SSC)-derived exosomes (SSC-Exos) would promote meniscal healing and prevent secondary osteoarthritis progression., Study Design: Controlled laboratory study., Methods: SSCs were isolated from bone marrow and exosomes were extracted via ultracentrifugation. The cell migration capabilities after incubation with exosomes were validated through in vitro cell culture. Full-thickness longitudinal medial meniscal tears were performed in the avascular region of 40 male Sprague-Dawley rats and 20 male New Zealand White rabbits, which were randomly divided into 2 groups: group treated with phosphate-buffered saline (G CON ) and group treated with exosomes (G Exosome ). The effects of these treatments on meniscal healing and secondary osteoarthritis were evaluated by gross inspection, biomechanical testing, and histological assessment. RNA sequencing of in vitro cell cultures was performed to explore the underlying mechanisms., Results: Exosomes were successfully extracted and identified. These exosomes significantly promoted cell migration capabilities in vitro ( P < .01). The G Exosome exhibited greater cell proliferation and tissue regeneration with type 2 collagen secretion, and a significantly higher meniscal repair score than that of the G CON at 8 weeks postoperatively ( P < .05). In contrast to the degenerative changes in both the meniscus and articular cartilage of the G CON , meniscal tissue in the G Exosome exhibited restoration of normal morphology with a smooth and glossy white surface and better mechanical strength at 8 weeks after meniscal repair. Both degeneration scores and synovitis scores were significantly higher in the G CON than in the G Exosome ( P < .05). Compared with the G CON , the expression of key genes related to cell migration, such as the chemokine family, was enhanced by exosome injection, leading to an upregulation of extracellular matrix expression while downregulating the expression of inflammation-related genes such as CD68 and the matrix metalloproteinase family., Conclusion: The administration of SSC-Exos effectively promoted meniscal healing in the avascular region and ameliorated secondary osteoarthritis. The effect might be attributed to inflammation modulation, promotion of cell migration, and secretion of extracellular matrix components., Clinical Relevance: Injection of SSC-Exos represents a promising therapeutic option for promoting meniscal healing in the avascular region., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by National Natural Science Foundation of China (No. 82072428, No. 823B2057) and Natural Science Foundation of Beijing, China (No. 7212132). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Arthroscopic treatment is recommended for hip synovial chondromatosis. However, evidence regarding long-term clinical outcomes is limited., Purpose: To evaluate long-term patient-reported outcomes (PROs) and survival, and to determine the potential effect of residual loose bodies, as evaluated by immediate postoperative computed tomography (CT), on clinical outcomes., Study Design: Case series; Level of evidence, 4., Methods: A consecutive cohort of patients undergoing arthroscopic treatment and diagnosed with synovial chondromatosis between March 2010 and May 2015 were included in the study. Preoperative radiography, CT, and magnetic resonance imaging were performed. Preoperative, midterm (minimum of 4 years), and long-term (minimum of 8 years) PROs were collected for visual analog scale for pain, modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), and 12-item international Hip Outcome Tool (iHOT-12). The percentages achieving minimal clinically important difference (MCID) were calculated. PROs and survival were compared between patients with and without residual loose bodies evident on immediate postoperative CT scan., Results: A total of 28 patients (20% of patients were lost to follow-up) were included in the study with a mean follow-up period of 104.9 months (range, 96-139 months). PROs including visual analog scale for pain (preoperative, 3.8 ± 1.2; midterm, 0.9 ± 1.7; long-term, 0.8 ± 1.4), mHHS (preoperative, 66.4 ± 14.4; midterm, 92.8 ± 12.3; long-term, 93.5 ± 10.5), NAHS (preoperative, 45.2 ± 16.2; midterm, 81.8 ± 15.3; long-term, 83.1 ± 12.9), and iHOT-12 (preoperative, 48.4 ± 15.6; midterm, 69.3 ± 11.7; long-term, 72.7 ± 11.4) were improved at both midterm and long-term follow-up (all with P < .001). In total, 27 (96.4%), 28 (100%), and 26 (92.9%) patients achieved MCID for mHHS, NAHS and iHOT-12, respectively, at the long-term follow-up. No significant difference was found in any of the PROs and the rate of achieving MCID between midterm and long-term follow-up (all with P > .05). One patient (3.6%) underwent revision surgery. Among the 23 patients who had loose bodies on preoperative CT or radiographs, 14 patients (60.9%) with residual loose bodies evident on immediate postoperative CT demonstrated lower NAHS ( P = .045) and iHOT-12 ( P = .037) scores but a comparable survival ( P > .05) at long-term follow-up compared with those who did not have loose bodies., Conclusion: Arthroscopic treatment for hip synovial chondromatosis achieved satisfactory long-term clinical outcomes with strong survival. Most patients maintained or improved their overall functional status between midterm and long-term follow-up. Furthermore, patients with residual loose bodies had less favorable clinical outcomes, although the survival rate was comparable., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Unrepairable massive rotator cuff tears (UMRCTs) are challenging to surgeons owing to the severely retracted rotator cuff musculotendinous tissues and extreme defects in the rotator cuff tendinous tissues., Purpose: To fabricate a tendon stem cell-derived exosomes loaded scaffold (TSC-Exos-S) and investigate its effects on cellular bioactivity in vitro and repair in a rabbit UMRCT model in vivo., Study Design: Controlled laboratory study., Methods: TSC-Exos-S was fabricated by loading TSC-Exos and type 1 collagen (COL-I) into a 3-dimensional bioprinted and polycaprolactone (PCL)-based scaffold. The proliferation, migration, and tenogenic differentiation activities of rabbit bone marrow stem cells (BMSCs) were evaluated in vitro by culturing them in saline, PCL-based scaffold (S), COL-I loaded scaffold (COL-I-S), and TSC-Exos-S. In vivo studies were conducted on a rabbit UMRCT model, where bridging was repaired with S, COL-I-S, TSC-Exos-S, and autologous fascia lata (FL). Histological and biomechanical analyses were performed at 8 and 16 weeks postoperatively., Results: TSC-Exos-S exhibited reliable mechanical strength and subcutaneous degradation, which did not occur before tissue regeneration. TSC-Exos-S significantly promoted the proliferation, migration, and tenogenic differentiation of rabbit BMSCs in vitro. In vivo studies showed that UMRCT repaired with TSC-Exos-S exhibited significant signs of tendinous tissue regeneration at the bridging site with regard to specific collagen staining. Moreover, no significant differences were observed in the histological and biomechanical properties compared with those repaired with autologous FL., Conclusion: TSC-Exos-S achieved tendinous tissue regeneration in UMRCT by providing mechanical support and promoting the trend toward tenogenic differentiation., Clinical Relevance: The present study proposes a potential strategy for repairing UMRCT with severely retracted musculotendinous tissues and large tendinous tissue defects., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by the National Natural Science Foundation of China (grant No. 82072426). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: After anterior cruciate ligament reconstruction (ACLR), single-leg horizontal hop distance limb symmetry index (LSI) >90% is recommended as a cutoff point for safe return to sport (RTS). However, athletes after ACLR have abnormal lower limb biomechanics despite an adequate single-leg hop distance LSI, implying that athletes are at high risk of reinjury. Symmetry of single-leg vertical jump height appears to be more difficult to achieve and can be a better representation of knee function than single-leg horizontal hop distance., Hypothesis: Athletes after ACLR with single-leg jump height LSI >90% had similar biomechanical characteristics to healthy athletes., Study Design: Controlled laboratory study., Level of Evidence: Level 3., Methods: A total of 46 athletes after ACLR were divided into low jump height (LJH, jump height LSI <90%, n = 23) and high jump height (HJH, jump height LSI >90%, n = 23) groups according to symmetry of single-leg vertical jump height, while 24 healthy athletes acted as a control (CONT) group. One-way analysis of variance was used to compare the kinematic and kinetic characteristics of the LJH, HJH, and CONT groups during single-leg vertical jump., Results: Both the LJH and HJH groups demonstrated greater limb asymmetry (lower LSI) during landing compared with the CONT group in knee extension moment ( P < 0.05), peak knee flexion angle ( P < 0.05), and knee power ( P < 0.05)., Conclusion: Symmetry in single-leg vertical jump height does not represent normal lower limb biomechanics in athletes after ACLR., Clinical Relevance: Symmetrical jump height may not signify ideal biomechanical or RTS readiness, but single-leg vertical jump test can be used as a supplement to horizontal hop test or other functional tests to reduce the likelihood of false-negative results in the absence of detailed biomechanical evaluation., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: Despite reassuring scientific data, the lay press and social media continue to propagate largely unsubstantiated claims that a significant number of athletes have died from cardiovascular complications related to COVID-19 vaccines. The present study sought to determine the incidence of COVID-19 vaccine cardiovascular complications in Team USA athletes., Hypothesis: It was predicted that there would be a low incidence of cardiovascular complications from COVID-19 vaccination in Team USA athletes., Study Design: Descriptive epidemiology study., Level of Evidence: Level 4., Methods: A retrospective review was conducted on the United States Olympic and Paralympic Committee electronic medical record, inclusive of athletes who represented Team USA in the 2020 Tokyo and 2022 Beijing Olympic and Paralympic Games, for COVID-19 vaccine cardiac complications including sudden cardiac arrest/death, myocarditis, pericarditis, and myopericarditis. Vaccination status (ie, fully vaccinated, yes or no), date of vaccination and eligible boosters, and type of vaccination during the study period were abstracted from the electronic medical record., Results: A total of 1229 athletes represented Team USA during the 2020 Tokyo (Olympic, 697; Paralympic, 237) and 2022 Beijing Games (Olympic, 229; Paralympic, 66). For the 2020 Tokyo Games, 73.8% of Olympians and 80.6% of Paralympians with available vaccination status had completed a primary vaccine series. For the 2022 Beijing Games, 100% of Olympians and Paralympians with available vaccination status were fully vaccinated. No athletes suffered sudden cardiac arrest/death or were diagnosed with myocarditis, pericarditis, or myopericarditis after COVID-19 vaccination., Conclusion: The data demonstrate an overall willingness of elite athletes to receive recommended COVID-19 vaccination coupled with a complete absence of vaccine-related cardiac complications in >1 year of follow-up., Clinical Relevance: Supposedly, this is the first study to investigate the incidence of COVID-19 vaccine cardiovascular complications in elite athletes. These data are an important first step to better inform cardiologists and sports medicine physicians who care for elite athletes., Competing Interests: The following authors declared potential conflicts of interest: A.B.S. has received consulting fees from the USOPC. J.T.F. has received royalties from UpToDate and Demos Publishing. A.L.B. has received grants from the National Institute of Health/National Heart, Lung and Blood Institute, the National Football Players Association, and the American Heart Association, and consulting fees from the USOPC, US Soccer, US Rower, the New England Patriots, the Boston Bruins, the New England Revolution, and Harvard University. W.M.A. has received royalties from Springer Nature, consulting fees from Korey Stringer Institute and Emerja Corp, and has stock or stock options in My Normative and Emerja Corp.

Background: The association between ligamentous knee injuries and corticospinal tract (CST) structure has attracted attention; however, any causal relationship remains uncertain. We performed Mendelian randomization (MR) analysis to identify the causal effects of ligamentous knee injuries on the CST., Hypothesis: Ligamentous knee injuries impair CST microstructure (ie, by reducing fractional anisotropy [FA] and increasing mean diffusivity [MD])., Study Design: MR analysis., Level of Evidence: Level 2., Methods: MR uses genetic variants as instrumental variables to infer causal relationships between exposures and outcomes. Summary data for ligamentous injuries in knee and CST structure were obtained from genome-wide association study datasets. Significant and independent (5 × 10 -6 ; r 2 < 0.001; 10,000 kb) single-nucleotide polymorphisms were extracted for MR analysis. Three methods for MR analysis were used (hypothesis-driven 1-tailed inverse variance weighted, MR-Egger, and weighted median), and sensitivity analyses were conducted to test reliability and stability., Results: Results from 3 MR methods consistently demonstrated that ligamentous knee injuries increased MD of the right CST (β, 0.063; 90% CI, 0.003-0.123; P = 0.04), and weak statistical significance suggested increased MD of the left CST (β, 0.060; 90% CI, -0.002 to -0.121; P = 0.05). However, no significant causal relationships were observed in CST FA, and no significant pleiotropy or heterogeneity was observed. Sensitivity analysis utilizing 2-tailed tests had no significant associations between ligamentous knee injuries and changes in CST structure., Conclusion: There is statistically weak genetic evidence that corticospinal pathway abnormalities may evolve after ligamentous knee injuries, which manifests as abnormally organized neurites., Clinical Relevance: Ligamentous knee injuries require attention not only to damage to the structure of the knee joint itself but also to the process of maladaptive neuroplasticity that leads to structural and functional changes of the CST; novel interventions that target the corticospinal pathway may provide subsequent treatment of ligamentous knee injuries., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Context: Access to real-time data that provide accurate and timely information about the status and extent of disease spread could assist management of the COVID-19 pandemic and inform decision-making., Aim: To demonstrate our experience with regard to implementation of technical and architectural infrastructure for a near real-time electronic health record-based surveillance system for COVID-19 in Iran., Method: This COVID-19 surveillance system was developed from hospital information and electronic health record (EHR) systems available in the study hospitals in conjunction with a set of open-source solutions; and designed to integrate data from multiple resources to provide near real-time access to COVID-19 patients' data, as well as a pool of health data for analytical and decision-making purposes., Outcomes: Using this surveillance system, we were able to monitor confirmed and suspected cases of COVID-19 in our population and to automatically notify stakeholders. Based on aggregated data collected, this surveillance system was able to facilitate many activities, such as resource allocation for hospitals, including managing bed allocations, providing and distributing equipment and funding, and setting up isolation centres., Conclusion: Electronic health record systems and an integrated data analytics infrastructure are effective tools to enable policymakers to make better decisions, and for epidemiologists to conduct improved analyses regarding COVID-19., Implications: Improved quality of clinical coding for better case finding, improved quality of health information in data sources, data-sharing agreements, and increased EHR coverage in the population can empower EHR-based COVID-19 surveillance systems., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Rotator cuff tears have been repaired using the transosseous method for decades. The direct suture (DS) technique has been widely used for rotator cuff tears; however, the retear rate is relatively high. Suture anchors are now used frequently for rotator cuff repair (RCR) in accordance with recent developments in materials. However, polyether ether ketone (PEEK) may still cause complications such as the formation of cysts and osteophytes. Some studies have developed the inlay suture (IS) technique for RCR., Purpose/hypothesis: To compare how 3 different surgical techniques-namely, the DS, IS, and PEEK suture anchor (PSA)-affect tendon-bone healing after RCR. We hypothesized that the IS technique would lead to better tendon-to-bone healing and that the repaired structure would be similar to the normal enthesis., Study Design: Controlled laboratory study., Methods: Acute infraspinatus tendon tears were created in 36 six-month-old male rabbits, which were divided into 3 groups based on the technique used for RCR: DS, IS, and PSA. Animals were euthanized at 6 and 12 weeks postoperatively and underwent a histological assessment and imaging. The expression of related proteins was demonstrated by immunohistochemistry and immunofluorescence staining. Mechanical properties were evaluated by biomechanical testing., Results: At 12 weeks, regeneration of the enthesis was observed in the 3 groups. However, the DS group showed a lower type I collagen content than the PSA and IS groups, which was similar to the results for scleraxis. The DS group displayed a significantly inferior type II collagen expression and proteoglycan deposition after safranin O/fast green and sirius red staining. With regard to runt-related transcription factor 2 and alkaline phosphatase, the IS group showed upregulated expression levels compared with the other 2 groups., Conclusion: Compared with the DS technique, the PSA and IS techniques contributed to the improved maturation of tendons and fibrocartilage regeneration, while the IS technique particularly promoted osteogenesis at the enthesis., Clinical Relevance: The IS and PSA techniques may be more beneficial for tendon-bone healing after RCR., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Objectives: To examine the effects of acupuncture and therapeutic exercise alone and in combination on temporomandibular joint symptoms in tension-type headache and to evaluate the potential interaction of existing temporomandibular dysfunction on the success of headache treatment., Design: Pre-planned secondary analysis of a randomized controlled, non-blinded trial., Setting: Outpatient clinic of a German university hospital., Subjects: Ninety-six Participants with frequent episodic or chronic tension-type headache were randomized to one of four treatment groups., Interventions: Six weeks of acupuncture or therapeutic exercise either as monotherapies or in combination, or usual care. Follow-up at 3 and 6 months., Main Measures: Subjective temporomandibular dysfunction symptoms were measured using the Functional Questionnaire Masticatory Organ, and the influence of this sum score and objective initial dental examination on the efficacy of headache treatment interventions was analyzed., Results: Temporomandibular dysfunction score improved in all intervention groups at 3-month follow-up (usual care: 0.05 [SD 1.435]; acupuncture: -5 [SD 1.436]; therapeutic exercise: -4 [SD 1.798]; combination: -3 [SD 1.504]; P  = 0.03). After 6 months, only acupuncture (-6 [SD 1.736]) showed a significant improvement compared to the usual care group ( P  < 0.01). Subjective temporomandibular dysfunction symptoms had no overall influence on headache treatment., Conclusions: Only acupuncture had long-lasting positive effects on the symptoms of temporomandibular dysfunction. Significant dental findings seem to inhibit the efficacy of acupuncture for tension-type headache., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Study Design: Retrospective Cohort Study., Objectives: This study aimed to develop survival prediction models for spinal Ewing's sarcoma (EWS) based on machine learning (ML)., Methods: We extracted the SEER registry's clinical data of EWS diagnosed between 1975 and 2016. Three feature selection methods extracted clinical features. Four ML algorithms (Cox, random survival forest (RSF), CoxBoost, DeepCox) were trained to predict the overall survival (OS) and cancer-specific survival (CSS) of spinal EWS. The concordance index (C-index), integrated Brier score (IBS) and mean area under the curves (AUC) were used to assess the prediction performance of different ML models. The top initial ML models with best performance from each evaluation index (C-index, IBS and mean AUC) were finally stacked to ensemble models which were compared with the traditional TNM stage model by 3-/5-/10-year Receiver Operating Characteristic (ROC) curves and Decision Curve Analysis (DCA)., Results: A total of 741 patients with spinal EWS were identified. C-index, IBS and mean AUC for the final ensemble ML model in predicting OS were .693/0.158/0.829 during independent testing, while .719/0.171/0.819 in predicting CSS. The ensemble ML model also achieved an AUC of .705/0.747/0.851 for predicting 3-/5-/10-year OS during independent testing, while .734/0.779/0.830 for predicting 3-/5-/10-year CSS, both of which outperformed the traditional TNM stage. DCA curves also showed the advantages of the ensemble models over the traditional TNM stage., Conclusion: ML was an effective and promising technique in predicting survival of spinal EWS, and the ensemble models were superior to the traditional TNM stage model., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Background: Rehabilitation after anterior cruciate ligament ACL reconstruction (ACLR) is crucial for safe return to play (RTP) and reducing the chances of a reinjury. Yet, there is no consensus on the ideal functional tests to assess rehabilitation progress in soccer players after ACLR., Purpose: The primary objective was to highlight the existing gap in the literature concerning the most effective standardized rehabilitation protocols and testing for facilitating successful RTP among soccer players., Study Design: Systematic review; Level of evidence, 4., Methods: A systematic review using PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) was conducted. Inclusion criteria encompassed original studies (level of evidence 1-4) that examined rehabilitation protocols, metrics of knee rehabilitation, and clinical outcomes after ACLR in soccer players., Results: This review incorporated 23 studies, predominantly retrospective case series, with a total number of 874 soccer players who underwent ACLR and rehabiliation. 5 (21.7%) studies utilized an accelerated rehabilitation protocol, while 7 (30.4%) of studies utilized a criterion-based rehabilitation. A wide heterogeneity of data was extracted including functional tests of rehabilitation and RTP such as strength test batteries, hop test batteries, and movement quality assessments. Of the 23 selected studies, 2 (8.7%) used all 3 test batteries, 8 (34.8%) used 2 test batteries, 12 (52.2%) used 1 test battery, and 1 (4.3%) used 0 of the test batteries. The mean time between surgery and RTP ranged from 3 to 8 months with only 2 (8.7%) studies reporting complications after ACLR. Lastly, out of the total studies examined, 9 (39.1%) assessed patient-reported outcome measures (PROMs), all of which demonstrated significant improvement from the initial assessment to the final follow up., Conclusion: Soccer-specific rehabilitation after ACLR lacks standardization. Even though many studies have assessed protocols for optimal RTP and reduced secondary ACL injuries, there is a gap in the literature regarding the most effective protocols and RTP testing. The methodology reported by Kyritsis et al could serve as a foundation for future prospective randomized multicenter studies to establish a standard rehabilitation protocol and enable a successful return to soccer., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: I.S.H. is a biostatistical consultant for LifeNet Health. B.M.S. has received consulting fees from Bioventus and support for education from Arthrex, Smith+Nephew, Peerless Surgical, Medwest Associates, and DePuy Synthes. R.S.L. has received consulting fees from Medtronic, support for education from Sea Pearl and Arthrex, and hospitality payments from Wright Medical Technology. P.F.D. has received support for education from Liberty Surgical. L.R. has received support for education from Arthrex and hospitality payments from Arthrosurface. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Context: Patients experiencing pain from femoral acetabular impingement and considering hip arthroscopy may be concerned about their timeline to resume activities they enjoy, such as golf., Objective: The purpose of this study was to review current literature on return-to-play data after hip arthroscopy and to provide clinicians with data to set proper expectations with patients., Data Sources: The following terms were used to search PubMed and Embase electronic databases on October 18, 2023: hip, arthroscopy, arthroscopic, golf., Study Selection: Studies were included if they were in the English language, of Level 1 to 4 evidence, and contained data specific to golfers undergoing hip arthroscopy. Studies were excluded if they did not designate participants as golfers or did not specify return-to-play data. Editorials, case reports, and review articles were excluded. Screening was completed by 2 authors in a blind and duplicate manner., Study Design: Systematic review., Level of Evidence: Level II., Data Extraction: The following datapoints were extracted from each study: hip pathology and arthroscopic procedure data; number of players returning to golf and time from surgery to return; outcome score(s); and rehabilitation details. Descriptive statistics were calculated using Comprehensive Meta-Analysis software., Results: The search returned 400 studies, of which 4 were included for analysis. Of these 4 studies, 2 specified return-to-play time. Of 95 golfers, 90 (94.7%) returned to golf successfully after arthroscopic hip surgery. Subjective and objective outcome scores improved postoperatively, including an increased average drive distance., Conclusion: Return to golf after hip arthroscopy is highly probable, with approximately 95% of patients throughout literature returning to play. A mean return time of 4.7 months for professional golfers and 7.2 months for amateurs, alongside improved subjective outcomes and performance metrics postsurgery, suggest patients can expect a relatively quick return to the course with similar or improved performance., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

This retrospective study investigates the effectiveness of a nursing intervention based on Orem's self-care model of nursing with elderly patients with femoral head necrosis who underwent total hip arthroplasty. Postoperative outcomes in the intervention and control groups were assessed by the visual analog scale (VAS), Barthel index, and Harris Hip Score (HHS). Participants in the intervention group had significantly better outcomes in terms of VAS, Barthel index, and HHS. The occurrence of pneumonia was significantly different between the groups. Those who underwent Orem's self-care model of nursing intervention were highly satisfied with their status postoperatively compared with the control group., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the authorship and/or publication of this review.

Background: Tibial tubercle osteotomy (TTO) is a well-established surgical treatment option for patellofemoral instability and pain. TTO with distalization (TTO-D) is indicated for patients with patellofemoral instability, patellar malalignment, and patella alta. The current literature demonstrates several complications that may be associated with TTO, with reportedly higher rates of complications associated with TTO-D., Purpose: To analyze and compare complication rates after TTO without distalization (TTO-ND) and TTO-D and assess risk factors associated with complications., Study Design: Cohort study; Level of evidence, 3., Methods: All skeletally mature patients who underwent TTO with or without distalization by a single surgeon between September 2014 and May 2023 with a minimum of 6 months of clinical follow-up were retrospectively reviewed. Patient factors, surgical indications, perioperative data, and complications were collected via a retrospective review of electronic medical records. Concomitant procedures were categorized as intra-articular, extra-articular, and osteotomies., Results: A total of 251 TTOs (117 TTO-D, 134 TTO-ND) were included in the study group. Postoperative complications were observed in 15 operations (6%), with arthrofibrosis as the most common complication (10 operations [4%]). TTO-D and TTO-ND had similar rates of complication (5% vs 7%; P = .793). Clinical nonunion was observed in 3 operations (3%) in the TTO-D cohort and 1 operation (1%) in the TTO-ND cohort. In the TTO-D cohort, concomitant intra-articular procedures were significantly associated with an increased likelihood of complications in a univariate model. In the TTO-ND cohort, an increased tourniquet time was significantly associated with an increased likelihood of complications in a univariate model. For all TTOs as well as the TTO-D and TTO-ND cohorts, there were no significant associations between patient or surgical variables in a multivariate model., Conclusion: TTO with and without distalization is a safe procedure with low rates of complication. TTO-D was not associated with a higher rate of complications compared with TTO-ND. There was no association between complications and surgical variables for TTO procedures., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: A.H.G. has received consulting fees from JRF, Moximed, Smith & Nephew, and Vericel; research support from Cartiheal, Moximed, Organogenesis, and Vericel; and speaking fees from Bioventus; and holds stock or stock options in Engage and Stryker. S.M.S. has received consulting fees from Smith & Nephew, Vericel, Flexion Therapeutics, and Miach; research support from Miach and Vericel; hospitality payments Bioventus, Aesculap Biologics, Zimmer Biomet Holdings, DePuy Synthes Sales, Joint Restoration Foundation, Dynasplint Systems, Pacira Therapeutics, Smith & Nephew, and Organanogenesis; and a gift from Engage Uni; and holds stock or stock options in Engage and Stryker. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: An athlete who returns to sport after an anterior cruciate ligament (ACL) injury has a substantially high risk of sustaining a new secondary ACL injury. Because ACL injuries most frequently occur during cutting maneuvers, such movements should be at the center of research attention., Purpose: To investigate whether knee biomechanical parameters during side-step cutting maneuvers differ between female elite athletes with and without a history of ACL injury and to evaluate whether such parameters are associated with future secondary ACL injury., Study Design: Cohort study; Level of evidence, 2., Methods: A total of 756 female elite handball and soccer players, of whom 76 had a history of ACL injury, performed a sport-specific cutting task while 3-dimensional kinematics and kinetics were measured. ACL injuries were registered prospectively over an 8-year follow-up period. Seven knee-specific biomechanical variables were the basis for all analyses. Two-way analyses of variance were applied to assess group differences, whereas logistic regression models served to evaluate associations between the knee-specific variables and future secondary ACL injury., Results: When players with a previous ACL injury performed the cutting maneuver with their ipsilateral leg, they exhibited lower knee abduction angles (mean difference [MD], 1.4°-1.5°; 95% CI, 0.2°-2.9°), lower peak knee flexion moments (MD, 0.33 N·m/kg -1 ; 95% CI, 0.18-0.48 N·m/kg -1 ), lower peak knee abduction moments (MD, 0.27 N·m/kg -1 ; 95% CI, 0.12-0.41 N·m/kg -1 ), and lower peak knee internal rotation moments (MD, 0.06 N·m/kg -1 ; 95% CI, 0.01-0.12 N·m/kg -1 ) compared with injury-free players. When players performed the cut with their contralateral leg, no differences were evident ( P < .05). None of the 7 knee-specific biomechanical variables was associated with future secondary ACL injury in players with an ACL injury history ( P < .05)., Conclusion: Approximately 4 years after ACL injury, female elite team-ball athletes still unloaded their ipsilateral knee during cutting maneuvers, yet contralateral knee loading was similar to that of injury-free players. Knee biomechanical characteristics were not associated with future secondary ACL injury., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Extracorporeal shock wave therapy (ESWT) promotes tissue healing by modulating inflammation, which has implications for meniscal tear healing in the avascular zone., Purpose: To evaluate the effects of a single dose of radial ESWT on the healing process and inflammation of the meniscus and knee joints after meniscal tears in the avascular zone., Study Design: Controlled laboratory study., Methods: Avascular tears were induced in the medial meniscus (MM) of 72 Sprague-Dawley rats. One week postoperatively, the rats received a single session of radial ESWT with a Power+ handpiece (ESWT group; n = 36) or with a fake handpiece (sham-ESWT group; n = 36). The rats were then euthanized at 2, 4, or 8 weeks postoperatively. The MMs were harvested for analysis of healing (hematoxylin-eosin, safranin O-Fast Green, and collagen type 2 staining) and inflammation (interleukin [IL]-1β and IL-6 staining). Lateral menisci and synovia were obtained to evaluate knee joint inflammation (enzyme-linked immunosorbent assay of IL-1β and IL-6). Cartilage degeneration was assessed in the femurs and tibial plateaus using safranin O-Fast Green staining., Results: The ESWT group showed significantly better meniscal healing scores than the sham-ESWT group at 4 ( P = .0066) and 8 ( P = .0050) weeks postoperatively. The IL-1β level was significantly higher in the sham-ESWT group than in the ESWT group at 2 (MM: P = .0009; knee joint: P = .0160) and 8 (MM: P = .0399; knee joint: P = .0001) weeks. The IL-6 level was significantly lower in the sham-ESWT group than in the ESWT group at 2 (knee joint: P = .0184) and 4 (knee joint: P = .0247) weeks but higher at 8 weeks (MM: P = .0169; knee joint: P = .0038). The sham group had significantly higher osteoarthritis scores than the ESWT group at 4 (tibial plateau: P = .0157) and 8 (femur: P = .0048; tibial plateau: P = .0359) weeks., Conclusion: A single dose of radial ESWT promoted meniscal tear healing in the avascular zone, modulated inflammatory factors in the menisci and knee joints in rats, and alleviated cartilage degeneration., Clinical Relevance: Radial ESWT can be considered a potential option for improving meniscal tear healing in the avascular zone because of its ability to modulate inflammation., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by National Key R&D Program of China (2021YFA1201303), Clinical Research Plan of SHDC (SHDC2022CRT021), National Natural Science Foundation of China (81972129 and 82072521), The Introduction Project of Clinical Medicine Expert Team for Suzhou (SZYJTD201714), Shanghai Talent Development Funding Scheme (2020080), Science and Technology Innovation Project of General Administration of Sport of China (22KJCX010), and Medical Engineering Joint Fund of Fudan University (YG2022-14). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Bone morphogenetic protein 2 (BMP2) is an appealing osteogenic and chondrogenic growth factor for promoting tendon-bone healing. Recently, it has been reported that soluble vascular endothelial growth factor (VEGF) receptor 1 (sVEGFR1) (a VEGF receptor antagonist) could enhance BMP2-induced bone repair and cartilage regeneration; thus, their combined application may represent a promising treatment to improve tendon-bone healing. Moreover, BMP2 could stimulate skeletal stem cell (SSC) expansion and formation, which is responsible for wounded tendon-bone interface repair. However, whether the codelivery of BMP2 and sVEGFR1 increases tendon enthesis injury-activated SSCs better than does BMP2 alone needs further research., Purpose: To study the effect of BMP2 combined with sVEGFR1 on tendon-bone healing and injury-activated SSC lineage., Study Design: Controlled laboratory study., Methods: A total of 128 C57BL/6 mice that underwent unilateral supraspinatus tendon detachment and repair were randomly assigned to 4 groups: (1) untreated control group; (2) hydrogel group, which received a local injection of the blank hydrogel at the injured site; (3) BMP2 group, which received an injection of hydrogel with BMP2; and (4) BMP2 with sVEGFR1 group, which received an injection of hydrogel with BMP2 and sVEGFR1. Histology, micro-computed tomography, and biomechanical tests were conducted to evaluate tendon-bone healing at 4 and 8 weeks after surgery. In addition, flow cytometry was performed to detect the proportion of SSCs and their downstream differentiated subtypes, including bone, cartilage, and stromal progenitors; osteoprogenitors; and pro-chondrogenic progenitors within supraspinatus tendon enthesis at 1 week postoperatively., Results: The repaired interface in BMP2 with sVEGFR1 group showed a significantly improved collagen fiber continuity, increased fibrocartilage, greater newly formed bone, and elevated mechanical properties compared with the other 3 groups. There were more SSCs; bone, cartilage, and stromal progenitors; osteoprogenitors; and pro-chondrogenic progenitors in the BMP2 with sVEGFR1 group than that in the other groups., Conclusion: Our study suggests that the combined delivery of BMP2 and sVEGFR1 could promote tendon-bone healing and stimulate the expansion of SSCs and their downstream progeny within the injured tendon-bone interface., Clinical Relevance: Combining BMP2 with sVEGFR1 may be a good clinical treatment for wounded tendon enthesis healing., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by the National Natural Science Foundation of China (Nos. 82230085, 82272572, and 81974338), the Science and Technology Major Project of Changsha (No. kh2102015), and the Fundamental Research Funds for the Central Universities of Central South University (No. 2022ZZTS0855). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Previous studies have examined patients with chronic lateral ankle instability (CLAI) undergoing open and arthroscopic anterior talofibular ligament (ATFL) reconstruction, reporting equivalent clinical results between the 2 procedures. However, data on the magnetic resonance imaging (MRI) outcomes on cartilage health after the 2 procedures are limited., Purpose: To compare the cartilage MRI T2 values of the talar and subtalar joints between patients with CLAI undergoing open and arthroscopic ATFL reconstruction., Study Design: Cohort study; Level of evidence, 3., Methods: A prospective study was conducted on patients who underwent open or arthroscopic ATFL reconstruction between January 2018 and December 2019, with a mean follow-up duration of 3 years. MRI scans and American Orthopaedic Foot & Ankle Society (AOFAS) and Tegner score estimations were completed by patients ≤1 week before surgery, as a baseline measurement, and at a 3-year follow-up. A total of 21 healthy volunteers were included who underwent MRI at baseline. Cartilage health was evaluated using MRI T2 mapping. The talar and subtalar cartilage regions were segmented into 14 subregions., Results: At baseline, patients with CLAI had substantially higher T2 values in the medial anterior, medial center, medial posterior, and lateral center regions on the talus compared with the healthy controls ( P = .009, .003, .001, and .025, respectively). Remarkable increases in T2 values in the lateral posterior region on the talus were observed from baseline to follow-up in the open group ( P = .007). Furthermore, T2 values were considerably higher in the medial center, medial posterior, lateral posterior, and lateral posterior calcaneal facets of the posterior subtalar joint at follow-up in the arthroscopic group compared with the baseline values ( P = .025, .002, .006, and .044, respectively). No obvious differences in ΔT2 values were noted between the 2 groups at follow-up. The AOFAS and Tegner scores remarkably improved from baseline to follow-up for the 2 groups (open: 3.25 ± 0.58 vs 5.13 ± 0.81, P < .001; arthroscopic: 3.11 ± 0.90 vs 5.11 ± 1.08, P < .001), with no considerable difference between them., Conclusion: The elevated T2 values of cartilage could not be fully recovered after open or arthroscopic ATFL reconstruction. Both arthroscopic and open ATFL reconstruction displayed similar effects on cartilage health concerning ΔT2, but the arthroscopic group demonstrated more degenerative cartilage subregions than the open group., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This study was funded by Shanghai Pujian Program (No. 22PJ1401400) and the National Science Foundation, China (Nos. 82171911 and 82271968). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: An anterior cruciate ligament (ACL) injury accompanied by patellar instability (PI) is a topic that has gained orthopaedic surgeons' attention recently. Untreated PI is reportedly associated with worse clinical outcomes after isolated ACL reconstruction (ACLR) in patients after an ACL injury with PI. Nevertheless, the appropriate surgical approach and its long-term therapeutic effects in these patients remain unclear., Purpose: (1) To compare the clinical and radiological outcomes between isolated ACLR (iACLR) and combined ACLR and medial patellofemoral ligament reconstruction (cAMR) in patients after an ACL injury with PI and (2) to explore the correlations between these 2 procedures and clinical and radiological outcomes., Study Design: Cohort study; Level of evidence, 3., Methods: A total of 106 patients diagnosed with an ACL injury accompanied by PI between January 2016 and April 2021 were analyzed in this study. There were 34 patients excluded because of missing postoperative radiological data. Among the remaining 72 patients, 34 patients underwent iACLR, while 38 patients underwent cAMR. Demographic characteristics, intraoperative findings, and patient-reported outcomes (Lysholm score, subjective International Knee Documentation Committee score, and Tegner activity score) were prospectively collected. Patellar alignment parameters and worsening patellofemoral osteoarthritis (PFOA) features (evaluated with the modified Whole-Organ Magnetic Resonance Imaging Score) were analyzed longitudinally on magnetic resonance imaging. The Kujala score was used to evaluate the functional recovery of the patellofemoral joint, and redislocations of the patella were prospectively recorded. Finally, multivariate logistic regression analysis was used to explore the correlations between these 2 procedures and clinical (not achieving the minimal detectable change [MDC] for the Lysholm score) and radiological (worsening PFOA features) outcomes., Results: The mean follow-up duration was 28.9 ± 6.2 and 27.1 ± 6.8 months for the iACLR and cAMR groups, respectively ( P = .231). Significantly higher Lysholm scores (88.3 ± 9.9 vs 82.1 ± 11.1, respectively; P = .016) and subjective International Knee Documentation Committee scores (83.6 ± 11.9 vs 78.3 ± 10.2, respectively; P = .046) were detected in the cAMR group compared with the iACLR group postoperatively. The rates of return to preinjury sports were 20.6% and 44.7% in the iACLR and cAMR groups, respectively (difference, 24.1% [95% CI, 3.3%-45.0%]; P = .030). Moreover, the rates of worsening PFOA features were 44.1% and 18.4% in the iACLR and cAMR groups, respectively (difference, 25.7% [95% CI, 4.9%-46.4%]; P = .018). In addition, significantly higher Kujala scores (87.9 ± 11.3 vs 80.1 ± 12.0, respectively; P = .006), lower redislocation rates (0.0% vs 11.8%, respectively; difference, 11.8% [95% CI, 0.9%-22.6%]; P = .045), and significantly better patellar alignment were detected in the cAMR group compared with the iACLR group postoperatively. Furthermore, multivariate logistic regression analysis determined that iACLR and partial lateral meniscectomy were significantly correlated with not achieving the MDC for the Lysholm score and worsening PFOA features in our study population., Conclusion: In patients after an ACL injury with PI, cAMR yielded better clinical and radiological outcomes compared with iACLR, with better patellar stability and a lower proportion of worsening PFOA features. Furthermore, not achieving the MDC for the Lysholm score and worsening PFOA features were significantly correlated with iACLR and partial lateral meniscectomy. Our study suggests that cAMR may be a more appropriate procedure for patients after an ACL injury with PI, which warrants further high-level clinical evidence., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by the National Natural Science Foundation of China (31370945, 82002274, 82272579), Natural Science Foundation of Shanghai (19ZR1438500), Shanghai Rising-Star Program (21QC1401300), and Shanghai Science and Technology Committee (22dz1204700). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Treatment options for calcific tendinitis (CT) of the shoulder remain controversial. A consensus for an operative indication for this condition is lacking., Purpose: To compare nonoperative versus operative treatment for shoulder CT and analyze factors affecting the prognosis after treatment., Study Design: Cohort study; Level of evidence, 3., Methods: A total of 180 patients diagnosed with symptomatic CT between January 2017 and September 2021 were evaluated in this retrospective cohort study. There were 103 patients treated nonoperatively at our institution, which included the use of nonsteroidal anti-inflammatory drugs, acupuncture, steroid injections, extracorporeal shock wave therapy, and ultrasound-guided needle aspiration/percutaneous irrigation. However, 77 patients were treated with arthroscopic surgery after 6 months of failed nonoperative treatment. The visual analog scale (VAS) for pain, the Constant-Murley score, and imaging were used to assess and evaluate outcomes. Descriptive data, functional outcomes, and imaging findings were compared between the operative and nonoperative groups before and after propensity score matching. Additionally, prognostic factors including calcium deposit size, tendon infiltration by calcium deposits, involvement of single or multiple tendons, and occurrence of rotator cuff tears were analyzed by comparing the groups to determine their effect on treatment options and recovery., Results: Magnetic resonance imaging showed that the supraspinatus tendon (66.7%) was most commonly involved, followed by the infraspinatus (42.8%) and subscapularis (21.1%) tendons. Tendon infiltration by calcium deposits was observed in 84.4% of the patients, and rotator cuff tears occurred in 30.0% of the patients. After propensity score matching, there was no significant difference in changes in the Constant-Murley score (48.1 ± 25.4 vs 49.0 ± 22.8, respectively; P = .950) and VAS score (4.9 ± 2.3 vs 4.5 ± 1.9, respectively; P = .860) between the operative and nonoperative groups at the final follow-up. However, for patients with shoulder CT and without rotator cuff tears, there was a significant difference in changes in the Constant-Murley score (52.93 ± 25.18 vs 42.13 ± 22.35, respectively; P = .012) and VAS score (5.21 ± 2.06 vs 3.81 ± 1.98, respectively; P < .001) between the operative and nonoperative groups, but the recovery time in the operative group was longer than that in the nonoperative group (86.92 ± 138.56 vs 30.42 ± 54.97 days, respectively; P = .016). The results also showed that calcium deposit size, involvement of multiple tendons, and tendon infiltration by calcium deposits did not affect the recovery time after treatment. The survival analysis showed that rotator cuff tears affected the complete recovery of shoulder function., Conclusion: This study demonstrated no significant difference between nonoperative and operative treatment for patients with shoulder CT, on the whole. However, for patients with shoulder CT and without rotator cuff tears, the effect of operative treatment was better than that of nonoperative treatment; yet, operative treatment was shown to prolong the recovery time. Calcium deposit size, tendon infiltration by calcium deposits, and involvement of multiple tendons did not correlate with recovery time or the recovery of function. A rotator cuff tear was the only factor affecting the complete recovery of shoulder function., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by the National Natural Science Foundation of China (82102632, 82160412), Guangxi Natural Science Foundation (2020GXNSFBA297089), Youth and Talent Research Project of Guangxi Science and Technology (AD21220065), and Liuzhou Science and Technology Project (2021CBB0106). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Chronic lateral ankle instability that develops after ankle sprains has a severe, negative influence on the patient's lower extremity function. Anatomic repair or reconstruction of the lateral ankle ligament is an effective treatment for people with chronic lateral ankle instability who want to regain their preinjury levels of work and sport., Purpose: To determine the rate of return to sport (RTS) and related factors after anatomic lateral ankle stabilization (ALAS) surgery., Study Design: Systematic review and meta-analysis; Level of evidence, 4., Methods: Electronic databases including Medline, Embase, the Cochrane Library, and EBSCO Rehabilitation & Sports Medicine Source were searched from the earliest feasible entrance until August 2021. Articles reporting the number of patients who returned to sport after ALAS surgery and analyzing the relevant factors were included. The results were combined using proportion meta-analyses., Results: A total of 25 publications were reviewed, with a total of 1384 participants. Results showed that 95% of patients (95% CI, 91%-99%) returned to any sport, 83% (95% CI, 73%-91%) returned to their preinjury level of sport, and 87% (95% CI, 71%-98%) returned to competitive sport after surgery. The mean time to RTS was 12.45 weeks (95% CI, 10.8-14.1 weeks). Each decade of age increased the likelihood of RTS failure by 6%, and increases in body mass index (BMI) of 5 kg/m 2 raised the risk of RTS failure by 4%. The rate of RTS was higher in professional and competitive athletes (93%; 95% CI, 73%-100%) than in recreational athletes (83%; 95% CI, 76%-89%). Analysis showed no differences for arthroscopy versus open surgery, repair versus reconstruction, and early versus late weightbearing., Conclusion: In most cases, patients may return to some kind of sport after ALAS surgery, and some patients RTS at their preinjury level. The relative risk of RTS failure increases according to the magnitude of the increase in age and BMI. Elite athletes are more likely to return compared with nonelite athletes., Competing Interests: The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Total meniscectomy for treating massive meniscal tears may lead to joint instability, cartilage degeneration, and even progressive osteoarthritis. The meniscal substitution strategies for advancing reconstruction of the meniscus deserve further investigation., Hypothesis: A decellularized meniscal scaffold (DMS) modified with collagen affinity stromal cell-derived factor (C-SDF1α) may facilitate meniscal regeneration and protect cartilage from abrasion., Study Design: Controlled laboratory study., Methods: The authors first modified DMS with C-SDF1α to fabricate a new meniscal graft (DMS-CBD [collagen-binding domain]). Second, they performed in vitro studies to evaluate the release dynamics, biocompatibility, and differentiation inducibility (osteogenic, chondrogenic, and tenogenic differentiation) on human bone marrow mesenchymal stem cells. Using in vivo studies, they subjected rabbits that received medial meniscectomy to a transplantation procedure to implement their meniscal graft. At postoperative weeks 6 and 12, the meniscal regeneration outcomes and chondroprotective efficacy of the new meniscal graft were evaluated by macroscopic observation, histology, micromechanics, and immunohistochemistry tests., Results: In in vitro studies, the optimized DMS-CBD graft showed notable biocompatibility, releasing efficiency, and chondrogenic inducibility. In in vivo studies, the implanted DMS-CBD graft after total meniscectomy promoted the migration of cells and extracellular matrix deposition in transplantation and further facilitated meniscal regeneration and protected articular cartilage from degeneration., Conclusion: The new meniscal graft (DMS-CBD) accelerated extracellular matrix deposition and meniscal regeneration and protected articular cartilage from degeneration., Clinical Relevance: The results demonstrate that the DMS-CBD graft can serve as a potential meniscal substitution after meniscectomy., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by the Science and Technology Major Project of Changsha (No. kh2102015) and the National Natural Science Foundation of China (Nos. 82230085 and 82272572). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Osteoarthritis (OA) is a common joint disease that is characterized by inflammation and cartilage degradation. Death-associated protein kinase 1 (DAPK1) is a multi-domain serine/threonine kinase and has been reported to be involved in the progression of OA. However, its role and mechanism in OA remain unclear. Here, we found the expression of DAPK1 in OA cartilage tissues was higher than that in normal cartilage tissues. The expression of DAPK1 in chondrocytes was up-regulated by IL-1β. Knockdown of DAPK1 promoted cell viability and anti-apoptotic protein expression, while it inhibited the apoptosis rate and pro-apoptotic protein expressions in IL-1β-induced chondrocytes. In addition, DAPK1 inhibition reduced the levels of inflammatory cytokines and expressions of matrix metalloproteinases (MMPs), and increased the expressions of collagen II and aggrecan. The data of mechanistic investigation indicated that the expression of pigment epithelium-derived factor (PEDF) was positively regulated by DAPK1. Overexpression of PEDF attenuated the effects of DAPK1 knockdown on IL-1β-induced cell viability, apoptosis, inflammation, and cartilage degradation. Furthermore, PEDF overexpression restored the activity of the NF-κB pathway and NLRP3 inflammasome after DAPK1 knockdown. Collectively, down-regulation of DAPK1 inhibited IL-1β-induced inflammation and cartilage degradation via the PEDF-mediated NF-κB and NLRP3 inflammasome pathways., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Context: Postural control deficits arising from injured ankles are central to chronic ankle instability (CAI) and its persistent symptoms. This is usually measured by recording the center of pressure (CoP) trajectory during static single-leg stance using a stable force plate. However, existing studies have produced conflicting results on whether this mode of measurement adequately reveals the postural deficits in CAI., Objective: To determine whether postural control during static single-leg stance is impaired in CAI patients when compared with uninjured healthy controls., Data Sources: Literature databases, PubMed, Embase, Web of Science, Cochrane Library, Scopus, CINAHL, and SPORTDiscus, were searched from inception to April 1, 2022, using ankle-, injury-, and posture-related terms., Study Selection: Two authors independently performed the step-by-step screening of article titles, abstracts, and full texts to select peer-reviewed studies investigating CoP trajectory during static single-leg stance using a stable force plate in CAI patients and healthy controls. A total of 13,637 studies were reviewed, and 38 studies (0.003%) met the selection criteria., Study Design: Meta-analyses of descriptive epidemiological study., Level of Evidence: Level 4., Data Extraction: CoP parameters, sway directions, visual condition, and numerical data (means and standard deviations) were extracted., Results: The injured ankles of CAI patients had higher standard deviations of sway amplitude in both anterior-posterior and medial-lateral directions (standardized mean difference [SMD] = 0.36 and 0.31, respectively) under conditions of open eyes than controls. Higher mean sway velocity in anterior-posterior, medial-lateral, and total directions (SMD = 0.41, 0.37, and 0.45, respectively) with closed eyes was also found., Conclusion: CAI patients had deficits of postural control during static single-leg stance, and these deficits were identified by the CoP trajectory. Further methodological explorations of CoP parameters and corresponding test conditions are required to enhance the sensitivity and reliability of postural deficit assessments in CAI using force plates., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: Ankle sprain causes proprioceptor injuries and prolonged joint deafferentation, which might lead to maladaptive neuroplasticity in patients with chronic ankle instability (CAI), especially in the cerebellum. Previous studies have indicated the impairment of superior cerebellar peduncle (SCP), but the inferior cerebellar peduncle (ICP) and middle cerebellar peduncle (MCP) have not been fully analyzed., Hypothesis: The cerebellar peduncles of participants with CAI would have altered fractional anisotropy (FA) and orientation dispersion index (ODI) in comparison with healthy controls without ankle injury history. In addition, FA and ODI would be correlated with the duration or severity of the sensorimotor deficits in CAI., Study Design: Cross-sectional study., Level of Evidence: Level 3., Methods: A group of 27 participants with CAI and 26 healthy controls underwent diffusion-weighted imaging scanning, with the cerebellar peduncles as the regions of interest. The measures obtained by single-shell diffusion tensor imaging and the multishell neurite orientation dispersion and density imaging were used. Correlation analyses were performed to examine the potential relationship between the FA/ODI and both the normalized Y-balance scores and the durations of ankle instability., Results: The ipsilateral ICP of the injured ankle in participants with CAI showed significantly lower FA (Cohen d 95% CI, -1.33 to -0.21; P = 0.04) and marginally significant higher ODI (Cohen d 95% CI, 0.10 to 1.20, P = 0.08) when compared with the same measures in the control group, with the ODI being positively correlated with the duration of ankle instability ( r = 0.42, P = 0.03)., Conclusion: The ICP in participants with CAI exhibited impaired integrity and a trend of abnormally organized neurites in comparison with a healthy control group., Clinical Relevance: The impairments of ICP might be an ongoing part of the pathological process of CAI, having the potential to become a target for the diagnostic evaluation of this clinical entity., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: A reliable landmark and precise distances from the ligament attachments are needed for lateral ankle stabilization surgery. The distal fascicle of the anterior inferior tibiofibular ligament (AITFL) has been used to locate the anterior talofibular ligament (ATFL) or calcaneofibular ligament (CFL) centers on the fibula. However, there is no anatomic study to validate the distal fascicle of the AITFL as a landmark of lateral ankle ligament stabilization, and more importantly, the exact distances from the ATFL or CFL attachments to the distal fascicle of the AITFL are unknown., Methods: Sixteen frozen cadaveric specimens (8 paired specimens) with no previous history of ankle injury were used in this study. Whether the distal fascicle of AITFL was present in each specimen was confirmed. Then, the distances from the most distal insertion of the AITFL's distal fascicle to the footprint centers of the ATFL and CFL on the fibula were measured. All measurements were performed by 2 observers, and the intraobserver and interobserver reliabilities were analyzed by intraclass correlation coefficients (ICCs)., Results: The distal fascicle of the AITFL was found in all specimens (100%). The mean distance from the most distal insertion of the AITFL's distal fascicle to the footprint centers of the ATFL, CFL, and the intersection center of the 2 ligaments on the fibula was 6.0 to 7.1 mm, 11.5 to 13.2 mm, and 9.0 to 10.0 mm, respectively. Excellent interobserver and intraobserver agreement (all ICCs > 0.9, P  < .01) was shown in the anatomic measurements of these distances., Conclusion: In this cadaveric study, we found that the distal fascicle was a constant structure of the AITFL in the lateral ankle. The distances from the most distal insertion of the AITFL's distal fascicle to the ligamentous footprint centers were reliable and may be used to identify the origins of the ATFL and CFL for lateral ankle ligament reconstruction., Clinical Relevance: This anatomic study validates the AITFL's distal fascicle as a potential landmark and, more importantly, determines the range of distances from AITFL's distal fascicle to the attachment centers of lateral ankle ligaments by anatomic measurements. The data may be used to identify the ATFL and CFL for lateral ankle stabilization surgery and become particularly valuable for endoscopic or arthroscopic techniques., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. ICMJE forms for all authors are available online.

Background: Various muscle contraction modalities have differing effects on the musculoskeletal system. To understand the magnitude of these effects, the authors investigated the effects of eccentric and concentric contractions on the bone-tendon interface after rotator cuff repair in mice., Hypothesis: Eccentric contraction promotes healing of the bone-tendon interface after rotator cuff repair in mice better than other muscle contraction patterns., Study Design: Controlled laboratory study., Methods: The authors performed acute supraspinatus tendon repair of the right shoulder in 104 C57BL/6 mice. Animals were randomized into 4 groups postoperatively: control group (Con group), horizontal running group (Horz group), +15° uphill running group (Up group), and -15° downhill running group (Down group), with 26 animals in each group. At 4 and 8 weeks postoperatively, the authors removed the eyeball, collected blood samples, and extracted the supraspinatus tendon-humerus complex for histological, immunological, bone morphological, and biomechanical tests., Results: At 4 and 8 weeks postoperatively, the Down group exhibited a better collagen cell arrangement and fibrocartilage layer than the other 3 groups. At 4 weeks postoperatively, anti-inflammatory macrophages (M2 macrophages) were observed at the repair site in all groups except for the Con group. At 8 weeks postoperatively, M2 macrophages were withdrawn from the tendon site in all groups. The transforming growth factor β1 concentration in the Down group was greater than that in the other 3 groups at 4 weeks postoperatively, and it was higher than that in the Con group at 8 weeks postoperatively. The bone volume fraction, number of trabeculae, and thickness of trabeculae at the repair site in the Down group, as well as the ultimate strength and failure load in the biomechanical tests, were greater than those in the other 3 groups at 8 weeks postoperatively., Conclusion: Eccentric contraction promotes healing of the bone-tendon interface after rotator cuff repair in mice better than other muscle contraction patterns., Clinical Relevance: After clinical rotator cuff repair, patients can be rehabilitated by eccentric training to speed up the functional recovery of the shoulder joint., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by the Hubei Provincial Natural Science Foundation of China (No. 2019CFB397), Research Fund for Young Teachers of Wuhan Sports University and Donghu Scholar Program of Wuhan Sports University (2019), and Young and Middle-Aged Scientific Research Team Project of Wuhan Sports University (No. 21KT14). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Impaired knee extensor neuromuscular function has been frequently observed in individuals with patellofemoral pain (PFP); however, few researchers have aimed to understand the influence of sex on knee extensor neuromuscular function in this pathological population. The authors aimed to determine whether there are differences in knee extensor neuromuscular function between sexes in individuals with and without PFP., Hypothesis: Women with PFP would exhibit greater deficits in knee extensor neuromuscular function than men with PFP, compared with sex-matched individuals without PFP., Study Design: Cross-sectional, case-control study., Level of Evidence: Level 4., Methods: A total of 110 individuals were classified into 4 groups: women with PFP (n = 25); men with PFP (n = 30); women without PFP (n = 25); and men without PFP (n = 30). Knee extensor strength (isometric peak torque [PT]), activation (central activation ratio), early, late, and total phase rate of torque development (RTD 0-100 , RTD 100-200 , and RTD 20-80% ), and endurance (isokinetic average PT) were assessed using an isokinetic dynamometer. Group differences were assessed using a 2-way multivariate analysis of variance (sex by PFP)., Results: Both women and men with PFP exhibited lower knee extensor strength, activation, early, late, and total phase RTD, and endurance versus sex-matched individuals without PFP ( P < 0.05 for all comparisons). Women with PFP exhibited lower early phase (7.91 ± 2.02 versus 9.78 ± 2.43 N·m/s/kg; P < 0.01; Cohen d = 0.83), late phase (5.34 ± 1.02 versus 7.28±2.28 N·m/s/kg; P < 0.01; Cohen d = 1.37), and total phase (7.40 ± 2.57 versus 8.72 ± 2.57 N·m/s/kg; P = 0.03; Cohen d = 0.51) RTD than men with PFP., Conclusion: Compared with sex-matched pain-free individuals, women with PFP displayed lower RTD than men with PFP. Clinicians should note that among individuals with PFP, women are more likely to experience a greater impairment in their knee extensor torque-generating capacity than men., Clinical Relevance: Additional treatment strategies that effectively improve the ability to rapidly generate torque should be developed and implemented, especially when treating women with PFP., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: Unlike the adult meniscus, the fetal meniscus possesses robust healing capacity. The dense and stiff matrix of the adult meniscus provides a biophysical barrier for cell migration, which is not present in the fetal meniscus. Inspired by developmental characteristics, modifying the matrix of the adult meniscus into a fetal-like, loose and soft microenvironment holds opportunity to facilitate repair, especially in the avascular zone., Hypothesis: Modifying the dense and stiff matrix of the adult meniscus into a fetal-like, loose and soft microenvironment could enhance cell migration to the tear interface and subsequent robust healing capacity., Study Design: Controlled laboratory study., Methods: Fresh porcine menisci were treated with hyaluronidase or collagenase. The density and arrangement of collagen fibers were assessed. The degradation of proteoglycans and collagen was evaluated histologically. Cell migration within the meniscus or the infiltration of exogenous cells into the meniscus was examined. Dendritic silica nanoparticles with relatively large pores were used to encapsulate hyaluronidase for rapid release. Mesoporous silica nanoparticles with relatively small pores were used to encapsulate transforming growth factor-beta 3 (TGF-β3) for slow release. A total of 24 mature male rabbits were included. A longitudinal vertical tear (0.5 cm in length) was prepared in the avascular zone of the medial meniscus. The tear was repaired with suture, repaired with suture in addition to blank silica nanoparticles, or repaired with suture in addition to silica nanoparticles releasing hyaluronidase and TGF-β3. Animals were sacrificed at 12 months postoperatively. Meniscal repair was evaluated macroscopically and histologically., Results: The gaps between collagen bundles increased after hyaluronidase treatment, while collagenase treatment resulted in collagen disruption. Proteoglycans degraded after hyaluronidase treatment in a dose-dependent manner, but collagen integrity was maintained. Hyaluronidase treatment enhanced the migration and infiltration of cells within meniscal tissue. Last, the application of fibrin gel and the delivery system of silica nanoparticles encapsulating hyaluronidase and TGF-β3 enhanced meniscal repair responses in an orthotopic longitudinal vertical tear model., Conclusion: The gradient release of hyaluronidase and TGF-β3 removed biophysical barriers for cell migration, creating a fetal-like, loose and soft microenvironment, and enhanced the fibrochondrogenic phenotype of reparative cells, facilitating the synthesis of matrix and tissue integration., Clinical Relevance: Modifying the adult matrix into a fetal-like, loose and soft microenvironment via the local gradient release of hyaluronidase and TGF-β3 enhanced the healing capacity of the meniscus., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by the National Natural Science Foundation of China (No. 82172420, No. 32000923, No. 81802161), Beijing Municipal Natural Science Foundation (No. 7214304), and Beijing Municipal Science and Technology Commission (No. Z171100001017085). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Although Hill-Sachs lesions (HSLs) are assumed to be influenced by glenoid characteristics in the context of bipolar bone loss, little is known about how glenoid concavity influences HSL morphology., Purpose: To investigate the relationship between the native glenoid depth and HSL morphological characteristics., Study Design: Cross-sectional study; Level of evidence, 3., Methods: Computed tomography images of bilateral shoulders from 151 consecutive patients with traumatic unilateral anterior shoulder instability were retrospectively reviewed. Patients were categorized into flat (<1 mm), moderate (1-2 mm), and deep (>2 mm) groups based on the native glenoid depth measured from the contralateral unaffected shoulder. The HSL morphological characteristics included size (depth, width, length, and volume), location (medial, superior, and inferior extent), and orientation (rim and center angle). The glenoid characteristics included diameter, depth, version, and bone loss. The patient, glenoid, and HSL morphological characteristics were compared among the 3 depth groups. Subsequently, the independent predictors of some critical HSL morphological characteristics were determined using multivariate stepwise regression., Results: After exclusion of 55 patients, a total of 96 patients were enrolled and classified into the flat group (n = 31), moderate group (n = 35), and deep group (n = 30). Compared with those in the flat group, patients in the deep group were more likely to have dislocation (38.7% vs 93.3%; P = .009) at the primary instability and had a significantly larger number of dislocations (1.1 ± 1.0 vs 2.2 ± 1.8; P = .010); moreover, patients in the deep group had significantly deeper, wider, larger volume, more medialized HSLs and higher incidences of off-track HSLs (all P ≤ .025). No significant differences were detected among the 3 groups in HSL length, vertical position, and orientation (all P ≥ .064). After adjustment for various radiological and patient factors in the multivariate regression model, native glenoid depth remained the strongest independent predictor for HSL depth (β = 0.346; P < .001), width (β = 0.262; P = .009), volume (β = 0.331; P = .001), and medialization (β = -0.297; P = .003)., Conclusion: The current study sheds light on the association between native glenoid depth and the morphology of HSLs in traumatic anterior shoulder instability. Native glenoid depth was independently and positively associated with HSL depth, width, volume, and medialization. Patients with deeper native glenoids were more likely to have off-track HSLs and thus require more attention in the process of diagnosis and treatment., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This work was supported by the National Natural Science Foundation of China (grant No. 31972923), Shanghai Shenkang Hospital Development Center (grant No. 12017121), and the Basic Research Program of Shanghai Sixth People’s Hospital (grant No. vnms202105). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Adipokines represent a spectrum of bioactive molecules that could modulate fibroblastic and inflammatory processes. The role of adipokines in the pathogenesis of frozen shoulder (FS), a common musculoskeletal disorder characterized by chronic inflammation, remains obscure., Purpose: To evaluate whether adipokines contribute to the pathogenic mechanisms of FS and to evaluate any potential correlation of adipokines with patients' symptoms., Study Design: Controlled laboratory study., Methods: Shoulder capsule specimens were obtained from 10 patients with FS and 10 patients with shoulder instability (control group). The specimens were dyed using hematoxylin and eosin and immunohistochemically assessed with antibodies targeting adipokines, collagen I, collagen III, and tumor necrosis factor α. Immunoreactivity was graded from "no" to "strong" in a blinded manner. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) analysis was conducted. Before the surgery, patient-reported frequency of pain, severity of pain, stiffness, and shoulder range of motion were documented., Results: In comparison with the control group, patients with FS had significantly greater pain frequency, pain severity, and stiffness and more limited shoulder range of motion ( P < .001). Hematoxylin and eosin- and Masson trichrome-stained samples from the FS group displayed hypercellularity and increased collagen fibers. Immunohistochemistry and RT-qPCR analyses indicated that expression of adipokines was significantly increased in FS capsules compared with the control group. The expression of collagen I, collagen III, and tumor necrosis factor α was also increased in FS capsules. No significant correlation was noted between adipokine expression and patient-reported outcomes in the control group, whereas in patients with FS, adiponectin expression was correlated with pain frequency ( r = 0.78; P = .01) and stiffness ( r = 0.73; P = .02). Visfatin was also correlated with pain frequency ( r = 0.70; P = .02)., Conclusion/clinical Relevance: This study indicated a potential role for adipokines in the pathogenesis of FS and demonstrated a correlation between adipokine expression and patients' pain and stiffness.

Background: Patient-reported outcome measures (PROMs) have transitioned from primarily being used as research instruments to becoming increasingly used in the clinical setting to assess recovery and inform shared decision-making. However, there is a need to develop validated short-form PROM instruments to decrease patient burden and ease incorporation into clinical practice., Purpose: To assess the validity and responsiveness of a shortened version of the Western Ontario Shoulder Instability Index (Short-WOSI) when compared with the full WOSI and other shoulder-related PROM instruments., Study Design: Cohort study (diagnosis); Level of evidence, 2., Methods: This study was a secondary analysis of data collected as part of an institutional review board-approved, multicenter cohort of 1160 patients undergoing surgical stabilization for shoulder instability. The following PROMs were captured preoperatively and 2 years after surgery: WOSI, American Shoulder and Elbow Surgeons (ASES) score, the Single Assessment Numeric Evaluation (SANE), and 36-Item Health Survey (RAND-36). The cohort was split into 2 data sets: a training set to be used in the development of the Short-WOSI (n = 580) and a test set to be used to assess the validity and responsiveness of the Short-WOSI relative to the full WOSI, ASES, SANE, and RAND-36., Results: The Short-WOSI demonstrated excellent internal consistency before surgery (Cronbach α = .83) and excellent internal consistency at the 2-year follow-up (Cronbach α = .93). The baseline, 2-year, and pre- to postoperative changes in Short-WOSI and WOSI were closely correlated ( r > 0.90), with both demonstrating large effect sizes (Short-WOSI = 1.92, WOSI = 1.81). Neither the Short-WOSI nor the WOSI correlated well with the other PROM instruments before ( r = 0.21-0.33) or after ( r = 0.25-0.38) surgery. The Short-WOSI, WOSI, and SANE scores were more responsive than ASES and RAND-36 scores., Conclusion: The 7-item Short-WOSI demonstrated excellent internal consistency and a lack of floor or ceiling effects. The Short-WOSI demonstrated excellent cross-sectional and longitudinal construct validity and was similarly responsive over time as the full WOSI. Neither the Short-WOSI nor WOSI correlated with more general shoulder PROMs, underscoring the advantage of using instability-specific instruments for this population.

Background: The rerupture or need for revision after anterior cruciate ligament reconstruction (ACLR) is a serious complication. Preventive strategies that target the early identification of risk factors are important to reduce the incidence of additional surgery., Purpose: To perform a systematic review and meta-analysis to investigate risk factors for revision or rerupture after ACLR., Study Design: Systematic review and meta-analysis; Level of evidence, 4., Methods: Literature searches were performed in PubMed, Embase, and Web of Science from database inception to November 2021 and updated in January 2022. Quantitative, original studies reporting potential adjusted risk factors were included. Odds ratios (ORs) were calculated for potential risk factors., Results: A total of 71 studies across 13 countries with a total sample size of 629,120 met the inclusion criteria. Fifteen factors were associated with an increase in the risk of revision or rerupture after ACLR: male sex (OR, 1.27; 95% CI, 1.14-1.41), younger age (OR, 1.07; 95% CI, 1.05-1.08), lower body mass index (BMI) (OR, 1.03; 95% CI, 1.00-1.06), family history (OR, 2.47; 95% CI, 1.50-4.08), White race (OR, 1.32; 95% CI, 1.08-1.60), higher posterolateral tibial slope (OR, 1.15; 95% CI, 1.05-1.26), preoperative high-grade anterior knee laxity (OR, 2.30; 95% CI, 1.46-3.64), higher baseline Marx activity level (OR, 1.07; 95% CI, 1.02-1.13), return to a high activity level/sport (OR, 2.03; 95% CI, 1.15-3.57), an ACLR within less than a year after injury (OR, 2.05; 95% CI, 1.81-2.32), a concomitant medial collateral ligament (MCL) injury (OR, 1.62; 95% CI, 1.31-2.00), an anteromedial portal or transportal technique (OR, 1.36; 95% CI, 1.22-1.51), hamstring tendon (HT) autografts (vs bone-patellar tendon-bone [BPTB] autografts) (OR, 1.60; 95% CI, 1.40-1.82), allografts (OR, 2.63; 95% CI, 1.65-4.19), and smaller graft diameter (OR, 1.21; 95% CI, 1.05-1.38). The other factors failed to show an association with an increased risk of revision or rerupture after ACLR., Conclusion: Male sex, younger age, lower BMI, family history, White race, higher posterolateral tibial slope, preoperative high-grade anterior knee laxity, higher baseline Marx activity level, return to a high activity level/sport, an ACLR within less than a year from injury, a concomitant MCL injury, an anteromedial portal or transportal technique, HT autografts (vs BPTB autografts), allografts, and smaller graft diameter may increase the risk of revision or rerupture after ACLR. Raising awareness and implementing effective preventions/interventions for risk factors are priorities for clinical practitioners to reduce the incidence of revision or rerupture after ACLR.

Background: Rotator cuff tear size, fatty infiltration, and scapular morphology are correlated with tendon healing and functional outcomes after arthroscopic repair; however, the association between anteroposterior acromial coverage and the clinical outcomes of anteroposterior massive rotator cuff tears (AP-MRCTs; involving all 3 tendons) remains unclear., Purpose: To identify the association between AP acromial coverage and functional and radiological outcomes after arthroscopic repair of AP-MRCTs., Study Design: Cohort study; Level of evidence, 3., Methods: A total of 98 patients who underwent arthroscopic repair of AP-MRCTs between January 2015 and December 2020 were included in the study and classified according to whether anterior acromial coverage (AAC) was anterior (46 patients; positive AAC group) or posterior (52 patients; negative AAC group) to the scapular line on true lateral shoulder radiographs. Demographic characteristics, surgical details, and functional outcomes were prospectively collected. Acromial morphological features, global tear extension (GTE), the global fatty infiltration index (GFII), tendon integrity after repair, proximal humeral migration, and glenohumeral abduction were measured and calculated on radiographs or magnetic resonance imaging scans preoperatively and at 2 years postoperatively. Multivariate logistic regression was performed to identify the independent risk factors of a rotator cuff retear., Results: The positive AAC group showed larger AAC, posterior acromial tilt, and anterior acromial slope as well as smaller posterior acromial coverage compared with the negative AAC group. Postoperatively, the American Shoulder and Elbow Surgeons score (82.5 ± 8.3 vs 77.2 ± 11.5, respectively; P = .013), active abduction (157.8°± 27.1° vs 142.7°± 39.6°, respectively; P = .048), and glenohumeral abduction (45.6°± 10.4° vs 39.7°± 14.9°, respectively; P = .041) in the positive AAC group were significantly higher than those in the negative AAC group, while the retear rate (23.9% vs 44.2%, respectively; P = .035) and proximal humeral migration (1.7 ± 1.0 vs 2.3 ± 1.2 mm, respectively; P = .006) were significantly lower in the positive AAC group than in the negative AAC group. Smaller AAC (odds ratio [OR], 0.93 [95% CI, 0.87-1.00]; P = .040), larger GTE (OR, 1.03 [95% CI, 1.01-1.06]; P = .017), and a higher GFII (OR, 3.49 [95% CI, 1.09-11.19]; P = .036) were associated with an increased risk of a rotator cuff retear., Conclusion: Increased AAC was associated with a lower retear rate and better functional outcomes after arthroscopic repair of AP-MRCTs. A preliminary risk evaluation integrating GTE, the GFII, and AAC is recommended to consider the necessity of additional procedures for patients in need of arthroscopic rotator cuff repair.

Background: Ankle osteoarthritis is debilitating and usually affects relatively young people, often as a result of previous ankle traumas, frequently occurring in sports. Platelet-rich plasma (PRP) injections for ankle osteoarthritis have shown no evidence of benefit over the course of 26 weeks. Previous studies on PRP for knee osteoarthritis showed that clinically significant improvements with PRP occurred between 6 to 12 months in the absence of initial benefit. No studies have evaluated the effect of PRP from 6 to 12 months in ankle osteoarthritis., Purpose: To assess the efficacy of PRP injections in ankle osteoarthritis over the course of 52 weeks., Study Design: Randomized controlled trial; Level of evidence, 1., Methods: In this 52-week follow-up trial, 100 patients with ankle osteoarthritis were randomized to a PRP group or placebo (saline) group. Patients received 2 intra-articular talocrural injections: at inclusion and after 6 weeks. Patient-reported outcome measures were used to assess pain, function, quality of life, and indirect costs over 52 weeks., Results: Two patients (2%) were lost to follow-up. The adjusted between-group difference for the patient-reported American Orthopaedic Foot & Ankle Society score over 52 weeks was -2 points (95% CI, -5 to 2; P = .31) in favor of the placebo group. No significant between-group differences were observed for any of the secondary outcome measures., Conclusion: For patients with ankle osteoarthritis, PRP injections did not improve ankle symptoms and function over 52 weeks compared with placebo injections., Registration: NTR7261 (Netherlands Trial Register).

Background: Adipose-derived stem cell (ADSC) sheets have been shown to promote tendon-to-bone healing. However, conventional laboratory preparation methods for ADSC sheets are time-consuming and risky, which precludes their diverse clinical applications., Purpose: To explore the utility of off-the-shelf cryopreserved ADSC sheets (c-ADSC sheets) for rotator cuff tendon-to-bone healing., Study Design: Controlled laboratory study., Methods: The ADSC sheets were cryopreserved and thawed for live/dead double staining, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, scanning electron microscopy observation, and biomechanical testing. Clone formation, proliferative capacity, and multilineage differentiation of ADSCs within the c-ADSC sheets were assayed to explore the effect of cryopreservation on stem cell properties. A total of 67 rabbits were randomly divided into 4 groups: normal group (without supraspinatus tendon tears; n = 7), control group (repair alone; n = 20), fresh ADSC (f-ADSC) sheet group (repair; n = 20), and c-ADSC sheet group (repair; n = 20). Rabbit bilateral supraspinatus tendon tears were induced to establish a chronic rotator cuff tear model. Gross observation, micro-computed tomography analysis, histological or immunohistochemical tests, and biomechanical tests were conducted at 6 and 12 weeks after repair., Results: No significant impairment was seen in the cell viability, morphology, and mechanical properties of c-ADSC sheets when compared with f-ADSC sheets. The stem cell properties of ADSC sheets also were preserved by cryopreservation. At 6 and 12 weeks after the repair, the f-ADSC and c-ADSC sheet groups showed superior bone regeneration, higher histological scores, larger fibrocartilage areas, more mature collagen, and better biomechanical results compared with the control group. No obvious difference was seen between the f-ADSC and c-ADSC sheet groups in terms of bone regeneration, histological score, fibrocartilage formation, and biomechanical tests., Conclusion: c-ADSC sheets, an off-the-shelf scaffold with a high potential for clinical translational application, can effectively promote rotator cuff tendon-to-bone healing., Clinical Relevance: Programmed cryopreservation of ADSC sheets is an efficient off-the-shelf scaffold for rotator cuff tendon-to-bone healing.

Background: Increased femoral torsion (FT) or tibial torsion (TT) has been suggested to be a potential risk factor for recurrent patellofemoral instability. However, the influence of increased FT or TT on the postoperative clinical outcomes of recurrent patellofemoral instability has rarely been investigated., Purpose: To assess the effect of increased FT or TT on postoperative results in patients with recurrent patellofemoral instability after combined medial patellofemoral ligament reconstruction (MPFLR) and tibial tubercle transfer, along with the influence of other risk factors., Study Design: Cohort study; Level of evidence, 3., Methods: Out of 91 patients, the study's analyses included 86 patients with recurrent patellofemoral instability who were treated with MPFLR and tibial tubercle transfer and enrolled between April 2020 and January 2021. FT and TT were assessed using preoperative computed tomography images. According to the torsion value of FT or TT, patients were categorized into 3 groups for each of FT and TT: group A (<20°), group B (20°-30°), and group C (>30°). Patellar height, femoral trochlear dysplasia, and the tibial tuberosity-trochlear groove (TT-TG) distance were also assessed. Patient-reported outcome scores (Tegner, Kujala, International Knee Documentation Committee [IKDC], Lysholm, and Knee injury and Osteoarthritis Outcome Score [KOOS]) were evaluated pre- and postoperatively. Clinical failure of MPFLR was recorded. Subgroup analysis was conducted to evaluate the effect of increased FT or TT on the postoperative outcomes., Results: A total of 86 patients were enrolled with a median follow-up time of 25 months. At the final follow-up, all functional scores improved significantly. Patella alta, high-grade trochlear dysplasia, and increased TT-TG distance did not have any significant effect on the postoperative functional scores. Regarding FT, subgroup analysis indicated that all functional scores of group C were lower than those of groups A and B except the KOOS knee-related Quality of Life score. For TT, group C had lower scores than group A for all functional outcomes except Tegner and KOOS Quality of Life and lower scores than group B for Kujala, IKDC, KOOS (Symptoms and Sport and Recreation subscales), Tegner, and Lysholm scores. The comparison between group A and group B, whether for FT or TT, revealed no significant differences., Conclusion: For patients with recurrent patellofemoral instability, increased lower extremity torsion (FT or TT >30°) was associated with inferior postoperative clinical outcomes after combined MPFLR and tibial tubercle transfer.