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Purpose: The purpose of this study was to identify risk factors for subsequent meniscal surgery following anterior cruciate ligament (ACL) reconstruction (ACLR) in patients without recurrent ACL injury. Methods: Patients aged ≥14 years who underwent primary ACLR with minimum 1‐year follow‐up and without recurrent ACL injury were retrospectively reviewed. Patient demographics and surgical data at the time of ACLR were collected. Postoperative radiographs were used to measure femoral and tibial tunnel position, and posterior tibial slope. Univariate and multivariate analyses were performed to identify risk factors for subsequent meniscal surgery. Results: Of 629 ACLRs that fulfilled the inclusion criteria, subsequent meniscal surgery was performed in 65 [10.3%] patients. Multivariate analysis revealed that medial meniscal repair at the time of ACLR, younger age, anterior femoral tunnel position and distal femoral tunnel position were significantly associated with subsequent meniscal surgery (p < 0.001, p = 0.016, p = 0.015, p = 0.035, respectively). The frequency of femoral tunnel placement >10% outside of the literature‐established anatomic position was significantly higher in those who underwent subsequent meniscal surgery compared to those who did not (38.3% vs. 20.3%, p = 0.006). Posterior tibial slope and ACL graft type were not significantly associated with subsequent meniscal surgery. Conclusion: Medial meniscal repair at the time of ACLR, younger age and nonanatomic femoral tunnel placement were risk factors for subsequent meniscal surgery in patients without recurrent ACL injury. Femoral tunnel placement <10% outside of the native anatomic position is important to reduce the risk of subsequent meniscal surgery. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the postoperative outcomes of the all‐inside technique in arthroscopic anterior cruciate ligament reconstruction (ACLR). Methods: Patients who underwent ACLR using the all‐inside technique between 2018 and 2021 were retrospectively assessed. All patients were followed up for at least 2 years. Functional recovery and pain relief were assessed using the International Knee Documentation Committee (IKDC) score, Lysholm score, Knee Injury and Osteoarthritis Outcome Score (KOOS) and visual analogue scale (VAS). Instrumented laxity was assessed via side‐to‐side difference using the Kneelax3 arthrometer. Graft maturity was estimated using the signal‐to‐noise quotient value based on magnetic resonance imaging (MRI). Adverse events during and after the surgery were recorded. Results: A total of 78 patients were included in this study, with a mean age of 28.1 ± 7.6 years. The IKDC (p < 0.001), Lysholm (p < 0.001) and KOOS (p < 0.001 for all subgroups) scores at the final follow‐up were significantly higher than those before the surgery. The VAS scores (p < 0.05) were significantly lower than those before surgery. The side‐to‐side difference results indicated that 50 patients had a difference of less than 3 mm, indicating a tight graft, whereas only 1 patient had a difference of >5 mm, indicating a loose graft. The median signal‐to‐noise quotient of the graft on MRI was 1.4 (P25, P75: 1.0, 2.0). No intraoperative adverse events were observed. Postoperative adverse events included three cases of infection, three cases of graft rerupture, two cases of cyclops lesion and one case of surgical intervention for a meniscal tear. Conclusion: ACLR using the all‐inside technique offers promising results in patients with ACL rupture. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: To investigate sex‐based recovery differences in patients undergoing anterior cruciate ligament reconstruction (ACLR) with a hamstring (HT) or quadriceps (QT) tendon autograft. Methods: This study included 97 patients, including 50 females (HT = 25, QT = 25) and 47 males (HT = 24, QT = 23), assessed presurgery and at 12‐ and 24‐month postoperatively via surveys, laxity, isokinetic knee extensor and flexor torque and a 6‐hop performance battery. Limb symmetry indices (LSIs) were calculated. Outcomes were compared between males and females, as well as within each graft type. Results: Males reported significantly higher Tegner scores at 12 (p = 0.029) and 24 (p = 0.031) months, Anterior Cruciate Ligament Return to Sport after Injury scores at 12 (p = 0.009) and 24 (p = 0.010) months, and a significantly higher lateral hop LSI at 12 (p = 0.045) months, knee extensor torque LSI at 12 (p = 0.020) months, and knee flexor torque LSI at 12 (p = 0.001) and 24 (p = 0.039) months. Females undergoing ACLR with a QT (vs. HT) graft demonstrated a lower knee extensor torque LSI at 12 (p = 0.006) months, a lower lateral hop LSI at 12 (p = 0.038) months, and a lower medial hop LSI at 12 (p = 0.042) months. Conclusions: Females reported less activity and psychological readiness, as well as strength symmetry. Furthermore, the recovery of quadriceps strength and hop symmetry was delayed in females (vs. males) undergoing ACLR with a QT graft. A better understanding of these differences will assist in counselling on expectations, determining the most appropriate graft construct and permitting more targeted rehabilitation. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: Previous evidence indicated that the tibiofemoral bone configuration might elevate the risk of an anterior cruciate ligament (ACL) injury. Furthermore, a low hamstring‐to‐quadriceps muscle ratio predisposes especially females to unfavourable knee kinematics. The primary objective of the present study was to investigate sex‐specific associations between tibiofemoral bone geometry and isokinetic knee flexion torque in patients with primary ACL injury followed by ACL reconstruction. Methods: N = 100 patients (72 = male, 28 = female, age = 31.3 ± 10.2, body mass index = 25.3 ± 3.6) with primary ACL rupture with isokinetic knee flexion torque assessments before and 6 months after ACL reconstruction surgery were analysed. Magnetic resonance imaging scans were analysed for medial posterior tibial slope (MPTS) and lateral posterior tibial slope, notch width index (NWI) and lateral femoral condyle index (LFCI). Additionally, isokinetic knee flexion torque (60°/s) and hamstring–quadriceps ratios were evaluated. Subsequently, functional parameters were correlated with imaging data for gender subgroups. Results: The findings showed that presurgical isokinetic knee flexion torque was not associated with any marker of femoral or tibial bone geometry. Further, while significant differences were observed between female (0.883 ± 0.31 Nm/kg) and male (1.18 ± 0.35 Nm/kg) patients regarding preoperative normalized knee flexion torque (p < 0.001), no significant sex differences were found for percentage increases in normalized knee flexion torque from presurgery to postsurgery. Generally, female patients demonstrated significantly higher MPTS magnitudes (p < 0.05) and lower LFCI values (p < 0.05) compared to men. Conclusion: The present results demonstrated no association between tibial or femoral bone geometry and muscle strength of the hamstrings in patients with ACL reconstruction, indicating an important mismatch of muscular compensation to deviations in bone geometry. There were no sex‐specific differences in tibiofemoral bone parameters. Level of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to identify factors influencing persistent muscle weakness in knee flexor strength after anterior cruciate ligament (ACL) reconstruction using the hamstring tendon and establish a clear cut‐off value at 3 months postoperatively for the limb symmetry index (LSI) to exceed 90% at 6 months postoperatively. Methods: One hundred forty‐eight patients undergoing ACL reconstruction were included and categorised into two groups based on knee flexor strength at 6 months postoperatively: patients with LSI of 90% or greater (achieved group: n = 114) and patients with LSI less than 85% (nonachieved group: n = 34). Items with significant differences between the two groups (preoperative waiting period, LSI to body weight ratio of knee flexor and extensor strength at 3 months postoperatively and peak torque angle of knee flexor muscle) were included in the multiple logistic regression analysis. Additionally, a receiver operating characteristic curve was used to calculate the cut‐off value of the LSI at 3 months postoperatively, which was required to achieve the LSI criteria for knee flexor strength 6 months postoperatively. Results: Multiple logistic regression analysis extracted the preoperative waiting period and LSI for knee flexor strength at 3 months postoperatively. The cut‐off value at 3 months postoperatively was 76.9% (area under the curve value, 0.82; sensitivity, 0.76; and specificity, 0.81) of the LSI. Conclusion: The LSI of at least 76.9% for knee flexor strength at 3 months after ACL reconstruction was an indicator for achieving the 6 months postoperatively. This is a criterion to aim for, considering the stress on the graft and the regeneration process of the semitendinosus tendon. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: This study radiologically investigated the potential of preoperative recovery of the anterolateral ligament (ALL) in patients who did not undergo anterior cruciate ligament reconstruction (ACLR) surgery in the early stages despite surgical indication. The secondary aim was to investigate the relationship between ALL injuries in magnetic resonance imaging (MRI) and the results of Lachman and pivot shift tests performed preoperatively and postoperatively under anaesthesia among patients who underwent ACLR in acute and chronic stages. Methods: The study examined 100 patients aged 19–51 years who underwent anatomic single bundle ACLR using hamstring autografts for the ACL. Based on the time between the injury and ACLR, they were divided into acute (≤6 months) and chronic (>6 months) groups. The chronic group had three subgroups of ACLR times: 7–12, 13–24 and >24 months. Complete recovery was defined as a change from grade B or C upon injury to grade A before surgery according to the Muramatsu MRI classification. The relationship between preoperative and postoperative Lachman grades and pivot shifting test results and the degree of ALL injury was evaluated. Results: In the chronic group, 19/61 patients (31.1%) had preoperative grade A, and 4/61 patients (6.5%) had grade A at the time of injury. In the acute group, 22/29 patients with grades B and C (76%) had grade 3 preoperative pivot shifting. In the acute group, grades 1 and 2 were more common in patients with grades B and C (10/29, 35%) than grade A (0/10, 0.0%). Conclusion: The improvement rate was 24.6% among patients who did not receive ACLR in the acute phase and underwent ACLR in the chronic phase. In the acute group, the degree of ALL damage was related to the pivot shift results. However, the results in the chronic phase were not associated with the degree of injury. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: Risk factors for the development of symptomatic cyclops lesion after anterior cruciate ligament reconstruction (ACLR) surgery are not entirely identified yet. This study aimed to investigate whether the choice of hamstring graft (semitendinosus‐gracilis; STG vs. semitendinosus; ST) affects the risk of developing a symptomatic cyclops lesion after ACLR. Methods: This retrospective cohort study included 1416 patients receiving either an ST graft (n = 1209) or an STG graft (n = 207) ACLR with a follow‐up of at least 2 years. A persisting extension limitation was clinically determined, and cyclops lesions were confirmed by magnetic resonance imaging (MRI) and second‐look arthroscopy. Graft‐specific incidence of cyclops lesions was examined with χ2 test and combined with the factors number of graft bundles, graft diameter and sex evaluated with a binominal logistic regression model. Results: In total, 46 patients developed symptomatic cyclops lesions (3.2%), with 36 having ACLR with an ST graft (3.0%) and 10 with an STG graft (4.8%) (n.s). The mean time from ACLR to the second‐look arthroscopy for cyclops removal was 1.1 ± 0.6 years. Female patients were 2.5 times more likely to develop a cyclops lesion than male patients. Patients with an STG graft and larger graft diameters did not have a higher risk of developing cyclops lesions. Patients who received an STG graft with both tendons folded four times (double‐quadruple) had significantly higher risk of developing a cyclops compared with all other numbers of graft bundles combined (8.3%, respectively 3.0%; p = 0.014). Conclusion: This study could not prove an increased risk of developing a symptomatic cyclops lesion for patients with an STG graft compared with an ST graft used for ACLR. However, patients with a double‐quadruple ACLR had a higher percentage of cyclops lesions compared with all other numbers of graft bundles. Female sex was associated with an increased risk of developing cyclops lesions. Level of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: There remains a lack of consensus around autograft selection in anterior cruciate ligament reconstruction (ACLR), though there is a large body of overlapping systematic reviews and meta‐analyses. Systematic reviews and their methodological quality were aimed to be further assessed, using a validated tool known as assessing the methodological quality of systematic reviews (AMSTAR‐2). Methods: MEDLINE, Embase and CENTRAL were searched from inception to 23 April 2023 for systematic reviews (with/without meta‐analysis) comparing primary ACLR autografts. A final quality rating from AMSTAR‐2 was provided for each study ('critically low', 'low', 'moderate' or 'high' quality). Correlational analyses were conducted for ratings in relation to study characteristics. Results: Two thousand five hundred and ninety‐eight studies were screened, and 50 studies were ultimately included. Twenty‐four studies (48%) were rated as 'critically low', 17 (34%) as 'low', seven (14%) as 'moderate' and two (4%) as 'high' quality. The least followed domains were reporting on sources of funding (1/50 studies), the impact of risk of bias on results of meta‐analyses (11/36 studies) and publication bias (17/36 studies). There was a significant increase in the frequency of studies graded as 'moderate' compared to 'low' or 'critically low' quality over time (p = 0.020). Conclusion: The methodological quality of systematic reviews comparing autografts in ACLR is low, with many studies being rated lower due to commonly absent aspects of systematic review methodology such as investigating sources of funding and publication bias. More recent studies were generally more likely to be of higher quality. Authors are advised to consult AMSTAR‐2 prior to conducting systematic reviews in ACLR. Level of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: Environmental sustainability in medicine is a growing concern. Determining the carbon footprint of medical procedures may aid in selecting a less impactful technique moving forward. The purpose of this study was to understand the environmental impact of different anterior cruciate ligament reconstruction techniques, for which there is no consensus in terms of optimal graft. Methods: A life cycle analysis of different anterior cruciate ligament reconstruction techniques was performed. These included quadrupled semitendinosus graft, bone‐patellar tendon‐bone graft, iliotibial band augmented with gracilis graft, doubled semitendinosus and doubled gracilis graft, and quadriceps tendon graft. All procedures were systematically paired with a lateral extra‐articular procedure. The study was conducted in a specialised centre using surgeon preference cards, with the help of a dedicated organisation for calculation according to the ISO 14044 standard. The primary outcome measure was the carbon footprint of each of the five techniques. Secondary outcomes included other environmental impact indicators, including human carcinogenic toxicity and mineral resource scarcity, among others, based on the ReCiPe 2016 midpoint guideline. The analysis had three scopes, each encompassing varying numbers of processes: graft implantation, full procedure, and entire environmental impact, from medical prescription to patient discharge. Results were reported as percentage increases compared to the graft technique with the lowest environmental impact. Results: It was demonstrated that the surgical procedure itself accounted for <40% of the life cycle, with arthroscopy being 88% of surgery's GHG emissions, and scrubbing and draping contributing 39% to the carbon footprint. The iliotibial band augmented with gracilis tendon technique had the lowest carbon footprint (0.199 Kg Co2 eq), and the least impact in most categories at all scopes of the life cycle analysis. Using this technique as a reference, in terms of graft implantation, it was determined that extensor mechanism grafts had the highest carbon footprint (300% higher than the reference). Greater scopes showed a similar trend, with percentage differences decreasing significantly, reaching 1–3% when considering the entire environmental impact for most categories. Nevertheless, among the aforementioned factors of the ReCiPe 2016 guidelines, the semitendinosus graft paried with a lateral extra‐articular procedure displayed greater difference in human carcinogenic toxicity and mineral resource scarcity (6% and 10% respectively) compared to the reference. The individual processes with the highest impact were also highlighted. Conclusions: In the institution where the study was conducted, the studied iliotibial band graft option was found to have the lowest environmental impact. Such analyses of standardised procedures can be replicated in individual institutions in order to determine their environmental impact. Identification of procedures with comparable results and differing environmental consequences may influence the future decision‐making process. Level of Evidence: Level II, prospective cohort study. [ABSTRACT FROM AUTHOR]

Purpose: A debilitating complication following anterior cruciate ligament reconstruction is a secondary meniscus tear. Currently, the literature is mixed regarding the risk factors associated with the incidence of secondary meniscus tears. The aim of this study was to investigate risk factors associated with meniscus tears following an isolated primary anterior cruciate ligament reconstruction. ACL graft failure was hypothesized to be the strongest risk factor for secondary meniscal injury occurrence. Methods: A retrospective cohort analysis was performed using the PearlDiver Database. Patients with a primary anterior cruciate ligament reconstruction were identified in the database. Patients with concomitant knee ligament injury or meniscus injury present at the time the index procedure were excluded. Patients were grouped to those who had a secondary meniscus tear within 2 years following anterior cruciate ligament reconstruction and those who did not. Univariate analysis and multivariable regression analysis was conducted to identify significant risk factors for a secondary meniscus tear. Results: There were 25,622 patients meeting criteria for inclusion in this study. Within 2 years from the primary anterior cruciate ligament reconstruction, there were 1,781 patients (7.0%) that experienced a meniscus tear. Graft failure had the highest odds of having a postoperative meniscus tear within 2 years (OR: 4.1; CI 3.5–4.8; p < 0.002). Additional significant risk factors included tobacco use (OR: 2.0; CI 1.0–3.1; p < 0.001), increased Charlson Comorbidity Index (OR: 1.2; CI 1.1–1.4), male gender (OR: 1.1; CI 1.1–1.2; p < 0.001), obesity (OR: 1.1; CI 1.1–1.2; p < 0.001), delayed surgery (OR:1.1; CI 1.1–1.2; p < 0.002), and patients age 30 and older (OR: 1.0; CI 1.0–1.0; p < 0.001). Conclusions: This study found that anterior cruciate ligament graft failure is the strongest predictor of post-operative meniscus tears. Other risk factors, including tobacco use, increased CCI, male gender, obesity, delayed surgery, and age 30 and older, were established, with several being modifiable. Therefore, targeted preoperative optimization of modifiable risk factors and postoperative protocols may reduce the risk of secondary meniscus tears. Level of evidence: Level III, prognostic trial. [ABSTRACT FROM AUTHOR]

Purpose: The results after anterior cruciate ligament reconstruction (ACLR) are evaluated by laxity measures, functional tests, and patients' perception by patient-reported outcome measures (PROMs). It is not known, if one of these evaluation instruments is representative or if outcome scores from all must be reported to obtain a full evaluation of the condition. The aim was to study the correlations between these three types of outcomes 1 year after primary ACLR. Method: All adult patients (range 18–45 years) who had an ACLR between 1.1.2019 and 31.12.2021 were offered 1-year follow-up by an independent observer. Preoperative information about knee laxity and peroperative information about the condition of menisci and cartilage were registered. At 1-year follow-up clinical and instrumented knee stability and function assessed by four different hop tests were registered. Patients completed four PROMs (the Subjective International Knee Documentation Committee (IKDC) score, the Knee Numeric-Entity Evaluation Score (KNEES-ACL), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Lysholm score) and Tegner activity scale and answered anchor questions regarding satisfaction and willingness to repeat the operation. Results: A total of 190 adults attended the 1-year follow-up and 151 had all assessments. There were only a few positive and weak correlations between performance tests and PROMS and between clinical measurements and PROMS (r = 0.00–0.38), and the majority were of negligible strength. Tegner score had in general the highest correlation (low to moderate). The highest correlation was 0.53 (moderate) between the anchor question about patient satisfaction and Lysholm/IKDC scores. There was no difference in the correlations depending on meniscal condition. Conclusions: In ACLR patients there was no clinically relevant correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. Therefore, one type of outcome cannot represent the others. This is an argument for always to include and report all three types of outcomes, and conclusions based on one type of outcome may not be sufficient. Level of evidence: II. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the association between hamstring autograft diameter and ACL graft failure rate in athletes who successfully returned to pivoting sports after ACL reconstruction. Methods: Retrospective evaluation of ACL graft failure rates in athletes who underwent ACL reconstruction with all-inside hamstring autograft and successfully returned to pivoting sports following postoperative rehabilitation. Athletes were divided into a ≤ 8 mm group and a > 8 mm group. Data about return to pivoting sports and ACL graft failures after ACL reconstruction were collected via a digital questionnaire. ACL graft failures were in all cases confirmed by an orthopaedic surgeon and/or MRI. The association between hamstring autograft diameter and ACL graft failure rate was investigated using a Fisher's exact test in the subgroup of athletes who completed the digital questionnaire and returned to pivoting sports. Results: Two-hundred and twenty-nine of the 422 athletes who completed the digital questionnaire (54.2%) returned to a pivoting sport and were included for final analyses. Ninety-seven (42.4%) of the athletes who returned to sport were in the ≤ 8 mm group (8 graft failures) and 132 (57.6%) in the > 8 mm group (10 graft failures). There were significantly more women (49.5 and 13.6% respectively; p < 0.001) and significantly smaller (1.75 and 1.81 m respectively; p < 0.001), lighter (72.2 and 79.6 kg respectively; p < 0.001) and younger (23.6 and 26.1 years old respectively; p = 0.015) athletes in the ≤ 8 mm group compared to the > 8 mm group. There was no significant association between hamstring autograft diameter and ACL graft failure rate. Conclusion: A hamstring autograft diameter of ≤ 8 mm is a legitimate option for smaller, lighter and female athletes without increasing the risk for ACL graft failure. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: One-stage revision anterior cruciate ligament reconstruction (ACLR) with the anatomic rectangular tunnel (RT) technique using bone–patellar tendon–bone (BTB) grafts results in anatomically precise tunnel placement and secure graft fixation. This study evaluated knee joint laxity and clinical outcomes in terms of femoral tunnel overlap. It was hypothesised that there would be no significant differences in knee joint laxity or clinical outcomes regardless of femoral tunnel overlap. Methods: Between 2012 and 2021, a single surgeon conducted 196 one-stage revision ACLRs with the RT technique using BTB grafts. Patients were divided based on the presence of femoral tunnel overlap. Knee joint laxity was evaluated using the Lachman test, pivot shift test, and side-to-side difference measured with a KT-1000 arthrometer. Clinical outcomes were assessed using the Lysholm score, Knee Injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) Knee Examination Form 2000. Knee joint laxity and clinical outcomes were compared between groups after a median follow-up of 2.5 years (range 2.0–8.0). Results: The study included 30 and 73 patients in the overlap and non-overlap groups, respectively. No significant differences were observed in the results of the Lachman test, pivot shift test, or KT-1000 arthrometer as well as in the Lysholm, KOOS, or IKDC scores between the two groups. Based on the IKDC scores, all patients were graded as normal or nearly normal. Conclusion: One-stage revision ACLR with the RT technique using BTB grafts improved knee joint laxity and had favourable clinical outcomes regardless of femoral tunnel overlap. To achieve optimal results in one-stage revision ACLR, it is crucial to create a tunnel within the anatomical attachment area and ensure proper graft fixation and tensioning. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: Psychosocial interventions have shown potential in reducing the fear of re-injury after anterior cruciate ligament reconstruction (ACLR), but this has not been systematically reviewed. The aim of this study was to assess the available evidence on the effect of psychosocial interventions on kinesiophobia after ACLR. Methods: Two independent researchers conducted a systematic search in the electronic databases including Scopus, PubMed, Web of Science (WOS), SPORTDiscus, PsycINFO, and CINAHL from their inception until May 2022. They included studies that utilised a randomised controlled study design with a control group, and measured kinesiophobia using the Tampa Scale for kinesiophobia in patients who underwent primary ACLR. The outcome of interest was the mean and standard deviation of kinesiophobia. Extracted data were analysed using Comprehensive Meta-Analysis software, version 3.0 (CMA.V2), employing a random-effects model to calculate the overall effect estimates of psychosocial interventions on Kinesiophobia. The standardised mean difference with 95% confidence intervals (CIs) was computed based on the mean and standard deviation in each group. Results: This systematic review and meta-analysis included 5 randomised controlled trials with a total of 213 patients who underwent ACLR. The results of the meta-analysis showed that psychosocial intervention was more effective than non-psychosocial comparators in reducing kinesiophobia among patients who underwent a primary ACLR (5 trials, MD 0.56, 95% CI 0.28–0.83, p < 0.001). The heterogeneity score was zero (I2 = 0%; n.s. for Cochran's Q test), indicating no significant variation among the studies. Conclusions: Psychosocial interventions can alleviate kinesiophobia in patients with primary ACLR. Although the limited number of reviewed studies and their methodological limitations precludes drawing a definitive conclusion regarding the effectiveness of psychosocial interventions on kinesiophobia, these promising findings can serve as a basis for developing psychological strategies to manage kinesiophobia in patients with primary ACLR and can also guide future research this issue. Level of evidence: II. Trial registration: This trial is registered in PROSPERO on December 2021 (CRD42021282413). [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine the factors affecting knee extensor strength 6 months after anterior cruciate ligament (ACL) reconstruction using autograft hamstring tendon. Methods: 144 patients who could undergo regular follow-up after ACL reconstruction were divided into 2 groups: those with greater than 90% (Group A: n = 95) and less than 85% (Group B: n = 49) isokinetic knee contraction at 60°/s 6 months post-ACL reconstruction. Basic information, injury status, limited preoperative knee extension, and knee extensor strength at 3 and 6 months postoperatively were compared between the groups. Multivariate logistic analysis was performed and included variables that showed statistically significant differences between the groups in the univariate analysis. In addition, the cut-off value for the limb symmetry index (LSI) at 3 months postoperatively needed to exceed an LSI of 90% at 6 months postoperatively was calculated using the receiver operating characteristics curve. Results: Age, preoperative waiting period, limited preoperative knee extension, and knee extensor strength at 3 months postoperatively were significantly different between the two groups. The multivariate logistic analysis showed that all the variables affected the improvement in knee extensor strength at 6 months postoperatively. Limited preoperative knee extension was the most significant factor (odds ratio: 15.1, 95% confidence interval: 2.57–118.56, p < 0.01). The LSI cut-off value at 3 months postoperatively was 72.0%. Conclusion: Key factors in achieving the necessary knee extensor strength criteria for return to sports at 6 months post-ACL reconstruction include addressing limited preoperative knee extension and achieving an LSI ≥ 72% in knee extensor strength at 3 months postoperatively. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the morphology of the anterior cruciate ligament (ACL) femoral footprint with three-dimensional magnetic resonance imaging (3D MRI) in healthy knees. Methods: Fifty subjects with healthy knees were recruited, utilising 3D-SPACE sequences for ACL evaluation. The ACL was manually segmented, and the shape, size and location of the ACL femoral footprint were evaluated on a reformatted oblique-sagittal plane, which aligned closely with the ACL attachment. Statistical analysis included one-way ANOVA for continuous variables and Fisher's exact test for categorical variables, with a P value < 0.05 considered significant. Results: Three types of ACL femoral footprint shape were identified, namely, oblong-ovate (OO) in 33 knees (66%), triangular (Tr) in 12 knees (24%) and two-tears (TT) in 5 knees (10%), with the mean areas being 58, 47 and 68 mm2, respectively. Within group TT, regions with similar sizes but different locations were identified: high tear (TT-H) and low tear (TT-L). Notably, group OO demonstrated a larger notch height index, whilst group TT was characterised by a larger α angle and lateral femoral condyle index. A noticeable variation was observed in the location of the femoral footprint centre across groups, with group TT-L and group Tr showing a more distal position relative to the apex of the deep cartilage. According to the Bernard and Hertel (BH) grid, the ACL femoral footprint centres in group TT-L exhibited a shallower and higher position than other groups. Furthermore, compared to group OO and TT-H, group Tr showed a significantly higher position according to the BH grid. Conclusion: In this study, the morphology of the ACL femoral footprint in healthy young adults was accurately evaluated using 3D MRI, revealing three distinct shapes: OO, Tr and TT. The different ACL femoral footprint types showed similar areas but markedly different locations. These findings emphasise the necessity of considering both the shape and precise location of the ACL femoral footprint during clinical assessments, which might help surgeons enhance patient-specific surgical plans before ACL reconstruction. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to determine the efficacy of anterior cruciate ligament reconstruction (ACLR) using autograft combined with or without ligament augmentation. Methods: A computerized search of the databases was conducted, including PubMed, Web of Science, Embase, Scopus and the Cochrane Library. Only prospective or retrospective comparative studies with a minimum 2-year follow-up were considered for inclusion. Two independent reviewers performed data extraction and methodological quality assessment. A Mantel–Haenszel analysis was used for the pooling of results. Sensitivity analysis was performed to maintain the stability of results. The egger test was applied to assess the publication bias. Results: Fourteen studies were included. The total cohort was 1353 patients (non-augmented group: 763 patients; augmented group: 590 patients). There were three Randomized Controlled Trials (RCTs, Level I), six retrospective comparative studies (Level III) and five case–control studies (Level III). The follow-up rate was ≥ 88% and the follow-up periods were ≥ 24 months in all included studies. The augmented graft used to compare with autograft included the Ligament Augmentation Device (LAD), the Ligament Advanced Reinforcement System (LARS) artificial ligament, FiberTape, hamstring tendon allograft, degradable poly (urethane urea). No significant differences were observed between the augmented and non-augmented groups regarding postoperative patient-reported outcomes (PROs), including the International Knee Documentation Committee score, Lysholm score and Tegner score, knee laxity, including KT-1000, side-to-side difference, Lachman test and pivot shift and rate of graft failure. Conclusions: ACLR using autografts combined with ligament augmentation shows no advantages in PROs, knee laxity and graft failure rate compared with using autografts only. Level of evidence: Level III. Trial registration: The research protocol was registered at the PROSPERO database (CRD42022324784). [ABSTRACT FROM AUTHOR]

Purpose: Lateral posterior meniscal root tear (LPMRT) repair, at the time of anterior cruciate ligament (ACL) reconstruction are increasingly being performed. The aim of this study was to compare the clinical and functional outcomes, as well as the complication rates at a minimum of 2 years follow-up, between an isolated ACL reconstruction group with intact menisci and a combined ACL reconstruction and LPMRT repair group. Methods: All patients who underwent combined ACL reconstruction and LPMRT repair between 2016 and 2020 were included in the study. They were matched with an isolated ACL reconstruction group with intact menisci based on age, gender and the pre-injury IKDC score. The KOOS, ACLRSI Tegner-Lysholm score and the TELOS-test were collected pre- and postoperatively; complications (re-rupture, recurrence or persistence of a high grade pivot shift, new meniscal injury) were recorded. All LPMRTs were repaired using transtibial pull-out technique. Results: After matching, 100 patients were included in this study (mean age 29.6 ± 1.0 years and mean follow-up 42.9 ± 7.3 months): 50 patients in the isolated ACL reconstruction group with intact menisci (group A) and 50 in the combined ACL reconstruction and LPMRT repair group (group B). Preoperatively, patients in group B had significant lower KOOS scores (Global 55.9 ± 2.9 vs. 64.6 ± 2.3, p = 0.02), but similar ACLRSI, TEGNER and TELOS scores. At the last follow-up, all functional scores had improved, and no significant difference between the two groups on any score was observed. There was also no difference in terms of complications rates. Conclusion: At a minimum of 2 years follow-up (mean follow-up 42.9 months), LPMRT repair during ACL reconstruction has no significant difference in terms of post-operative functional outcomes compared to the isolated ACL reconstruction group. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: To perform a predictive analysis to identify preoperative patient factors associated with failure to achieve a newly defined patient acceptable symptom state (PASS) for the International Knee Documentation Committee (IKDC) Score after anterior cruciate ligament reconstruction (ACLR) in patients aged ≥ 40 years with a minimum of 2-year follow-up. Methods: This was a secondary analysis of a retrospective review of all patients aged 40 years or older receiving a primary allograft ACLR at a single institution between the years of 2005 and 2016, with 2-year minimum follow-up. Using an updated PASS threshold of 66.7 for the International Knee Documentation Committee (IKDC) score previously established for this patient cohort, a univariate and multivariate analysis was performed to identify preoperative patient characteristics predictive of failure to achieve PASS. Results: A total of 197 patients with a mean follow-up of 6.2 ± 2.1 years (range 2.7 – 11.2) were included in the analysis (48.5 ± 5.6 years, 51.8% female, Body Mass Index (BMI) 25.9 ± 4.4). PASS was achieved by 162 patients (82.2%). Patients who failed to achieve PASS more often had lateral compartment cartilage defects (P = 0.001) and lateral meniscus tears (P = 0.004), higher BMIs (P = 0.004), and Workers' Compensation status (P = 0.043) on univariable analysis. Factors predictive of failure to achieve PASS on multivariable analysis included BMI and lateral compartment cartilage defect (OR 1.12 [1.03–1.23], P = 0.013; OR 5.1 [1.87–13.9], P = 0.001). Conclusion: Among patients ≥ 40 years who receive a primary allograft ACLR, patients who fail to achieve PASS more often had lateral compartment cartilage defects and higher BMIs. Level of evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: Knee extension deficits complicate recovery from ACL injury and reconstruction; however, the incidence of knee extension loss is not well defined. The aim of this review was to identify the incidence of loss of extension (LOE) following ACL rupture and reconstruction, explore the definitions of knee extension deficits reported and identify prognostic factors affecting LOE incidence. Methods: A systematic search was conducted in Medline, Cochrane Library and PEDro for studies in publication up to November 2021, with no restrictions on publication year. References were screened and assessed for inclusion using predetermined eligibility criteria. Randomised controlled trials (RCTs) that quantified knee angle, loss of extension or incidence of extension deficit were included for quality assessment and data extraction. Statistical summaries were generated and meta-analyses performed in two parts to examine: (i) the probability of a datapoint being zero incidence compared to a nonzero incidence and (ii) the relationship between the predictors and nonzero LOE incidence. Results: A sample of 15,494 studies were retrieved using the search criteria, with 53 studies meeting eligibility criteria. The pooled results from 4991 participants were included for analysis, with 4891 participants who had undergone ACLR. The proportion of included studies judged at an overall low risk of bias was small (7.8%). The observed group and study were the most important predictors for whether a datapoint reported an incidence of extension deficit. Time to follow-up (P < 0.001) and graft type (P = 0.02) were found to have a significant influence on nonzero LOE incidence (%). Covariate adjusted estimates of average LOE indicated 1 in 3 patients presenting with LOE at 12 month follow-up, reducing to 1 in 4 at 2 years. Conclusions: This review examined the definitions for the measurement and interpretation of postoperative knee extension and established the trajectory of knee extension deficit after ACL injury and reconstruction. While factors associated with loss of extension were identified, the exact trajectory of knee extension deficits was difficult to infer due to discrepancies in measurement techniques and patient variation. On average, 1 in 3 patients may present with loss of extension of at least 3 degrees at 12-month follow-up, decreasing to 1 in 4 at 2 years. These results may be used by clinicians as an upper threshold for acceptable complication rates following ACLR. Future work should focus on LOE as a clinically relevant complication of ACL injury and treatment with appropriate attention to standardisation of definitions, measurements and better understanding of natural history. PROSPERO registration number: CRD42018092295. Level of evidence: Level I [ABSTRACT FROM AUTHOR]

PurposeA stringent outcome assessment is a key aspect for establishing evidence-based clinical guidelines for anterior cruciate ligament (ACL) injury treatment. The aim of this consensus statement was to establish what data should be reported when conducting an ACL outcome study, what specific outcome measurements should be used and at what follow-up time those outcomes should be assessed.MethodsTo establish a standardized approach to assessment of clinical outcome after ACL treatment, a consensus meeting including a multidisciplinary group of ACL experts was held at the ACL Consensus Meeting Panther Symposium, Pittsburgh, PA; USA, in June 2019. The group reached consensus on nine statements by using a modified Delphi method.ResultsIn general, outcomes after ACL treatment can be divided into four robust categories-early adverse events, patient-reported outcomes, ACL graft failure/recurrent ligament disruption and clinical measures of knee function and structure. A comprehensive assessment following ACL treatment should aim to provide a complete overview of the treatment result, optimally including the various aspects of outcome categories. For most research questions, a minimum follow-up of 2 years with an optimal follow-up rate of 80% is necessary to achieve a comprehensive assessment. This should include clinical examination, any sustained re-injuries, validated knee-specific PROs and Health-Related Quality of Life questionnaires. In the mid- to long-term follow-up, the presence of osteoarthritis should be evaluated.ConclusionThis consensus paper provides practical guidelines for how the aforementioned entities of outcomes should be reported and suggests the preferred tools for a reliable and valid assessment of outcome after ACL treatment.Level of evidenceV.

Purpose: Associated risk factors for the development of cyclops lesions have been little. Investigated, because most previous studies have limited their research to cases with symptomatic cyclops lesions (cyclops syndrome). The purpose of this study was to evaluate the presence of cyclops lesions using magnetic resonance image (MRI) at 6 and 12 months after anterior cruciate ligament reconstruction (ACL-R), and to investigate the associated risk factors of cyclops lesions and syndrome. Methods: A retrospective analysis of patients who underwent ACL-R using bone–patellar tendon–bone (BTPB) or hamstring tendon autograft from 2008 to 2017 was conducted. Predictor variables (age, sex, body mass index [BMI], time from injury to ACL-R, preinjury Tegner activity score, graft, meniscal and cartilage injury, and notch width index on MRI for the presence of cyclops lesions and syndrome were analyzed with multivariate logistic regression. Results: Four hundred and fifty-five patients (225 males and 230 females) were enrolled. One hundred and four patients (22.9%) had cyclops lesions, and all cyclops lesions were detected on MRI at 6 months post-operatively. In addition, 20 patients (4.4%) had cyclops syndrome which means that these were symptomatic cases. The risk factors for presence of cyclops lesions were BPTB autograft (OR = 2.85; 95% CI 1.75–4.63; P < 0.001) and female sex (OR = 2.03; 95% CI 1.27–3.25; P = 0.003). The presence of cyclops syndrome increased with graft (BPTB) (OR = 18.0; 95% CI 3.67–88.3; Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation P < 0.001), female sex (OR = 3.27; 95% CI 1.07–10.0; P = 0.038), and increased BMI (OR = 1.21; 95% CI 1.05–1.39; P = 0.008). Conclusions: All cyclops lesions were detected 6 months after ACL-R, and the majority of them were asymptomatic. BPTB autograft and female sex were the significant risk factors for the presence of cyclops lesions and syndrome. In addition, increased BMI was associated with a higher risk of developing cyclops syndrome. When BPTB autograft is used for a female patient, full active knee extension should be encouraged in the early period after ACL-R to prevent cyclops lesion formation. Level of evidence: Level IV, retrospective case series. [ABSTRACT FROM AUTHOR]

Purpose: To compare the midterm clinical outcomes of different meniscal surgeries in patients undergoing anatomic double-bundle anterior cruciate ligament reconstruction (DB-ACLR) with eight strands of hamstring (HT8) autografts and explore the potential predictive risk factors for residual knee laxity. Methods: From 2010 to 2017, a total of 410 patients who underwent anatomic trans-tibial DB-ACLR with HT8 autografts (169 patients without meniscal surgery, 105 patients with meniscal repair, and 136 patients with meniscal resection) were included in this study. The equivalent graft diameter was introduced to make the total graft size of DB-ACLR comparable with that of single-bundle ACLR and calculated as the square root of the quadratic sum of the diameter for each bundle. Residual laxity was defined as excessive anterior tibial translation or residual pivot shift at any follow-up visit, while graft rupture was confirmed by second-look arthroscopy or magnetic resonance imaging. Results: The mean follow-up period was 8.3 ± 2.2 years. The mean equivalent graft diameter was 9.9 ± 0.7 mm. Graft rupture was confirmed in 16 (3.9%) patients, while residual laxity was detected in 72 (17.6%) patients (34 [25.0%] in the meniscal resection group vs. 22 [13.0%] in the no meniscal surgery group, p = 0.021). In the multivariate logistic regression analysis, high-grade preoperative knee laxity (odds ratio OR 2.04, p = 0.020), equivalent graft diameter < 9 mm (OR 3.31 compared with 9–10 mm, p = 0.012; OR 3.28 compared with ≥ 10 mm, p = 0.019), and meniscal resection (OR 1.94 compared with no meniscal surgery, p = 0.045) were associated with residual laxity. Conclusion: During a midterm follow-up, meniscal resection increased the risk of residual knee laxity even in patients undergoing anatomic DB-ACLR with HT8 autografts. Increasing the hamstring graft diameter and preserving the menisci are important strategies for ACLR to restore knee stability. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

A 49-year-old woman underwent anatomic double-bundle anterior cruciate ligament reconstruction using a hamstring tendon. Due to knee osteoarthritis progression, total knee arthroplasty was performed 13 years after the surgery. The anteromedial (AM) bundle was composed partly of tendon-like tissue and partly of scar-like tissue. In the tendon-like part of the AM bundle, the collagen fibers were slightly loose and showed a low-frequency crimp structure with an ovoid cell shape. In contrast, the collagen arrangement in the scar-like part was irregular, edematous, and sparsely cell-dense, with an ovoid cell shape. The posterolateral bundles were generally composed of spindle-shaped cells, and the collagen was arranged in tight cohesion and had well-demarcated bundles with normal crimping. Within the tibial tunnel, the graft was mainly connected to the surrounding lamellar bone on the posterior sides, with sparser connections on the anterior and medial/lateral side. The findings of this long-term case provide valuable information to enable understanding of multiple-folded hamstring tendons. Level of evidence V. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of a new remnant-preserving double-bundle anterior cruciate ligament reconstruction (ACLR) technique, focused on avoiding remnant damage and preserving continuity of remnants, on graft maturity using magnetic resonance imaging (MRI). Methods: A total of 169 patients were divided into three groups: 41 in the preservation group, 70 in the resection group, and 58 in the absent group. In the preservation group, rather than passing the graft through the remnant tissue, the graft was reconstructed such that the anteromedial and posterolateral bundles sandwiched the remnant to avoid damage to the remnant and maintain its continuity. Based on 1-year postoperative MRI, the grafts were divided into three regions: distal, middle, and proximal. The signal/noise quotient (SNQ) of each region of interest was calculated to evaluate the signal intensity of the graft and was compared among the three groups. Additionally, to identify factors influencing graft maturity, a multiple regression analysis was performed with SNQ as the dependent variable and patient demographics, bone morphology, and surgical factors as independent variables. Results: In a three-group comparison of mean SNQs, the distal region was 3.3 ± 3.4, 8.9 ± 8.3, and 9.0 ± 8.6 (p < 0.001), the middle region was 5.3 ± 3.7, 10.9 ± 11.1, and 11.3 ± 10.2 (p < 0.001), and the proximal region was 6.8 ± 4.5, 11.1 ± 8.8, and 11.7 ± 10.8 (p = 0.017), in order of the preservation, resection, and absent groups, respectively. That indicated that the remnant-preserving ACLR was more hypointense than ACLR with remnant resection or absent in all three regions. Multiple regression analysis showed that remnant preservation remained the relevant factor affecting SNQ of the graft at the distal and middle levels. Conclusion: The new remnant-preserving anatomic double-bundle ACLR had significantly better graft maturity, measured by SNQ on MRI, than the remnant resection and absent groups. The remnant procedure was the relevant factor affecting graft maturity. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the extent of tunnel widening after anterior cruciate ligament reconstruction (ACLR) using the all-inside technique and to establish its correlation with patient-reported clinical outcomes and femoral graft bending angle (GBA). Methods: Tunnel widening was evaluated using computed tomography (CT)-based three-dimensional (3D) models, and the femoral GBA was directly measured on CT images using the Picture Archiving and Communication System (PACS) software. Clinical follow-up was routine procedure, and patient-reported clinical outcomes mainly included International Knee Documentation Committee (IKDC), Lysholm, and Knee Injury and Osteoarthritis Outcome Scores (KOOS) scores, and subjective knee stability assessment. Results: Fifty-two patients received standard all-inside ACLR, with a median follow-up of 6 months. Reconstructed anterior cruciate ligaments (ACLs) were scanned during the first 3 days and 6 months after surgery. On both the femoral and tibial sides, bone tunnels were most significantly enlarged at the articular aperture segment; the femoral tunnel was 9.2 ± 1.3 mm postoperatively and was significantly enlarged by 32% to a mean tunnel diameter of 12.1 ± 2.0 mm at 6 months after surgery. Moreover, the extent of tunnel enlargement gradually decreased as the measured levels approached those of the bone cortex. The femoral tunnel center was shifted into the anterior and distal direction, and the tibial tunnel center was shifted into the posterior and lateral direction. Additionally, the mean femoral GBA was 105.9° ± 8.1° at the 6-month follow-up. Tunnel enlargement and GBA were not significantly correlated with patient-reported outcomes. Conclusions: Femoral and tibial tunnels were significantly greater and eccentrically shifted at the 6-month follow-up after all-side ACLR. However, the extent of tunnel widening does not markedly affect the short-term clinical outcomes. Meanwhile, the femoral GBA was not significantly correlated with femoral tunnel widening or patient-reported outcomes. Although the tunnel widening following all-inside ACLR was not associated with clinical outcomes, it potentially caused difficulties in revision ACLR. Level of evidence: Level IV. [ABSTRACT FROM AUTHOR]

Purpose: Button implants with an adjustable-loop device (ALD) are often used in anterior cruciate ligament reconstruction (ACLR). Clinical research comparing ALDs with fixed-loop devices (FLD) has mainly been conducted in small patient populations with short follow-up times. To determine whether ALDs are safe to use in ACLR, a non-inferiority study with a large sample population and a long follow-up period would be beneficial. This study compared ALDs with FLDs to determine non-inferior revision surgery rates, knee stability, and patient-reported outcomes (PROM) in ACLRs. Methods: This non-inferiority register-based cohort study was conducted using data from the Danish Knee Ligament Reconstruction Registry (DKRR). A total of 12,723 patients > 15 years of age with primary ACLR using hamstring tendon autografts and either an FLD or ALD for femoral fixation were included: 9719 patients were in the FLD group, and 3014 patients were in the ALD group. The primary outcome was revision ACLR with a non-inferiority margin for ALDs at 4% at the 2-year follow-up. The secondary outcomes were anterior and rotatory knee stability and PROMs based on the Knee Injury and Osteoarthritis Outcome Score (KOOS) at the 1-year follow-up. Results: The crude cumulative revision rates in ALD implants at 2 and 5 years were 2.1% (95% CI 1.62–2.68) and 5.0% (95% CI 4.22–5.96), respectively. In the FLD group, the rates were 2.2% (95% CI 1.89–2.48) at 2 years and 4.7% (95% CI 4.31–5.20) at 5 years. The 1-year side-to-side differences were 0.97 mm (95% CI 0.90–1.03) in the ALD group and 1.45 mm (95% CI 1.41–1.49) in the FLD group. In the FLD group, 13% had a positive pivot shift, and in the ALD group, 6% had a positive pivot shift. There were no differences in KOOS. Conclusion: ALDs were non-inferior to FLDs regarding revision rates, knee stability, and patient-reported outcomes. Based on this conclusion, ALDs are safe to use for femoral fixation in ACLR. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the present study was to evaluate the long-term outcome of combined medial unicompartmental knee arthroplasty (UKA) and anterior cruciate ligament reconstruction (ACLR). The authors hypothesized that the combined procedure leads to good long-term outcome in patients with isolated medial knee osteoarthritis (OA) and anterior cruciate ligament (ACL) deficiency. Methods: Twenty-three patients with ACL deficiency and concomitant medial knee OA were treated from 2008 to 2016 with a combined UKA (Oxford Partial Knee) and ACLR using a hamstring tendon autograft. The follow-up assessment included VAS pain score, Lysholm score, Oxford Knee Score (OKS), American Knee Society scores (AKSS), International Knee Documentation Committee (IKDC 2000), Tegner and UCLA activity scores. Instrumented laxity test was done using the KT-1000 arthrometer. Survivorship analysis was performed using the Kaplan–Meier method. Implant loosening and disease progression was assessed by conventional radiography. Results: Average follow-up duration was 10 years (6–14.5). VAS, Lysholm, Tegner and UCLA scores improved significantly. OKS, AKSS and IKDC 2000 showed excellent results on follow-up. Implant survivorship was 91.4% at 14.5 years. There were 2 revisions with conversion to total knee arthroplasty at 6 and 12 years postoperatively due to trauma and disease progression, respectively. There were no radiological or clinical signs of instability or disease progression in any of the remaining knees. The side-to-side difference using the KT-1000 arthrometer was insignificant. Conclusions: UKA combined with ACLR is an effective therapeutic option with good outcome and return to sport rate on the long-term. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the differences in maximal (isometric and concentric peak torque) and explosive (rate of torque development (RTD)) hamstring and quadriceps strength symmetry between males and females during early- and late-phase rehabilitation after anterior cruciate ligament reconstruction (ACLR) using hamstring tendon (HT) autografts and to determine the interaction of time and sex on maximal and explosive strength symmetry. Methods: A total of 38 female and 51 male participants were assessed during early (3–6 months post-operative) and late (7–12 months post-operative) phases of rehabilitation following ACLR. Maximal (concentric and isometric peak torque) and explosive (isometric RTD) hamstring and quadriceps strength were assessed and presented as limb symmetry index (LSI). Results: Maximal concentric hamstrings asymmetry (Early: 86 ± 14; Late 92 ± 13; p = 0.005) as well as maximal concentric (Early, 73 ± 15; Late 91 ± 12; p < 0.001) and explosive (Early: 82 ± 30; Late: 92 ± 25; p = 0.03) quadriceps asymmetry decreased from early to late rehabilitation. However, there were no significant changes in maximal isometric quadriceps strength and explosive isometric hamstring strength in the same time period. Females had a larger asymmetry in maximal concentric (Females: 75 ± 17; Males: 81 ± 15; p = 0.001) and explosive (Females: 81 ± 32; Males: 89 ± 25; p = 0.01) quadriceps strength than males throughout rehabilitation. There were no sex differences in maximal and explosive hamstring strength. There were no sex by time interactions for any variables. Conclusion: Explosive hamstring strength asymmetry did not improve despite recovery of maximal hamstring strength during rehabilitation following ACLR with HT autografts. While sex did not influence strength recovery, females had larger maximal and explosive quadriceps strength asymmetry compared to males throughout rehabilitation following ACLR. Level of evidence: Level III [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to comparatively evaluate the accuracy of femoral tunnel positioning after anatomic single-bundle anterior cruciate ligament (ACL) reconstruction performed with the remnant preservation (RP) technique versus the non-remnant preservation (NRP) technique. Methods: A retrospective review of 145 patients who underwent ACL reconstruction from May 2020 to May 2022 were performed in this single-surgeon study. A total of 120 patients met the inclusion criteria and were allocated into two groups according to the surgical technique (i.e. RP group and NRP group). The relative location of the femoral tunnel in the lateral condyle was evaluated as a percentage using a standardized grid system on the three-dimensional computed tomography (3D-CT) image. The accuracy and precision of the RP group were assessed based on published anatomical data in direct comparison with the NRP group. Results: According to the surgical procedure, 57 of the 120 patients included were allocated into the RP group, and 63 into the NRP group. Significant differences were observed between the two groups in terms of tunnel position (posterior-to-distal (PD): 28.4 ± 5.4% (RP) vs. 31.8 ± 5.3% (NRP); P = 0.01), (anterior-to-posterior (AP): 32.6 ± 7.7% (RP) vs. 38.8 ± 7.7% (NRP); P = 0.00), while no significant differences were found in terms of the accuracy (8.6% (RP) vs. 8.9% (NRP); n.s) and precision (4.4% (RP) vs. 5.6% (NRP); n.s) of femoral tunnel positioning between the two groups. Conclusions: From this single-surgeon study, it was concluded that there were no differences in the creation of ACL femoral tunnel between the RP technique and the non-remnant preserving technique. Meanwhile, the RP technique would not sacrifice the ideal position of the femoral tunnel and is able to retain the possible benefits of the ACL stump. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: Anterior cruciate ligament (ACL) injuries are one of the most frequently studied injuries in orthopedic care and research. However, limited epidemiological data are available in Canada regarding trend and distribution of anterior cruciate ligament reconstruction (ACLR). In this paper, our purpose was to assess trends of ACLR between 2002/03 and 2018/19 by age, sex, season of surgery, and location (inpatient vs outpatient) of surgery. Methods: In this descriptive epidemiological study of retrospective data available from Alberta Ministry of Health, we report annual incidence of ACLR between 2002/03 until 2018/19 among Albertans aged 10 years and older. Information was collected by authors from physician claims database for primary ACLR and revision ACLR and linked with other databases. Incidence proportions (number of ACLR/100,000 population) were calculated and compared by age category and gender over the study period. Results: A total of 28,401 primary ACLR and 2085 revision ACLR were identified during the study period. Age-standardized annual incidence of primary ACLR increased from 40.6 to 51.2 per 100,000 population aged 10 years and older. Average annual increase in ACLR incidence was higher among females (1.8% per years) compared to males (0.96% per year). The overall peak incidence and peak incidence among males was observed in 20–29 year age group, whereas peak incidence in females was observed in 10–19 years of age. The number of ACLR in females outnumbers those among males for 10–19 year age group. Generally, a lower proportion of ACLR were conducted in summer compared to other seasons. Primary ACLR conducted in outpatient setting increased from 72% in 2002/03 to 97% in 2018/19. Conclusion: The incidence of ACLR is increasing in Alberta, especially among females and among younger cohorts under 20 years of age. This information can help clinicians to provide patient education and policy-makers to design and implement targeted ACL injury prevention programs. Level of evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate whether generalized joint hypermobility (GJH) influences postoperative results, including return to sport, patientreported outcomes, functional performance (hop tests), muscular strength, and the occurrence of ACL re-injury, in patients 1 year after anterior cruciate ligament (ACL) reconstruction. Methods: Data was extracted from a regional rehabilitation-specific registry containing information on patients with ACL injury. Patients between the ages of 16–50 years previously undergoing ACL reconstruction with available 1 year follow-up data were eligible for inclusion. Generalized joint hypermobility was assessed using the Beighton score (BS). Patients were examined one year postoperatively in terms of return to sport, patient-reported outcome, hop tests, muscular strength and the occurrence of reinjury. For purpose of analysis, patients were allocated into two groups, depending on the existence of GJH. The KOOS subscale of sports and recreation was considered the primary outcome. Analyses were performed both dichotomously and by using adjusted logistic regression, to consider potential confounders. Results: A total of 356 patients (41% males) were included, of which 76 (24% male) were categorized as having GJH. Patients with GJH had an inferior limb symmetry index preoperatively in terms of knee extension (mean 81.6 [SD 16.4] vs. 91.4 [SD 15.9], p = 0.02) and flexion strength (mean 91.9 vs. 99.1, p = 0.047) compared to patients without GJH. There was no difference between the groups in terms of the primary outcome, nor in any of the other postoperative outcomes. Nine patients (11.8%) in the group with GJH suffered ACL re-injury, compared with 13 patients (4.6%) in the control group (n.s.). Conclusion: One year after ACL reconstruction the existence of GJH did not affect postoperative patient satisfaction, strength or functional outcome. No conclusive statements can be made regarding the influence of GJH on the risk of ACL re-injury in this particular study. Level of evidence: Level II. [ABSTRACT FROM AUTHOR]

Purpose: To compare return to sport and clinical results in young active patients who underwent anatomic single-bundle (SB) versus double-bundle (DB) anterior cruciate ligament reconstruction (ACLR). Methods: Young active patients undergoing SB or DB ACLR from 2017 to 2019 at our institution were retrospectively reviewed. The primary outcome measures were the rate and time to return to sports, with secondary measures including the Lachman test, pivot shift test, Lysholm scores, International Knee Documentation Committee (IKDC) scores and graft rupture. Results: The study included a total of 90 patients (DB group, 42; SB group, 48), with a mean follow-up of 27.1 ± 6.1 months. Young active patients who underwent DB ACLR had a higher rate of return to pivoting sports than those who underwent SB ACLR (HR = 2.4; 95% confidence interval [CI]: 1.4, 4.1; p = 0.013). The DB group returned to pivoting sports at a mean ± SD of 11.0 ± 2.9 months compared with 12.7 ± 2.7 months in the SB group (p = 0.01). There was one traumatic failure in the SB group and one contralateral ACL rupture in the DB group. There was no significant difference in the rate and time to return to running, Lachman test, pivot-shift test, Lysholm or IKDC scores in either group. Conclusion: Both anatomical SB and DB techniques achieved satisfactory clinical outcomes. DB techniques led to superior performance of return to pivoting sports but nonsignificant differences in time and rate of return to running, passive stability measurement, subjective knee function outcome and graft rupture rate in both groups at the 2-year follow-up. The DB ACLR should be considered a viable option to treat young patients with high activity demands. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the correlation between femoral intercondylar notch volume and the characteristics of femoral tunnels in anatomical single bundle anterior cruciate ligament (ACL) reconstruction. Methods: Fifty-one subjects (24 male and 27 female: median age 27: range 15–49), were included in this study. Anatomical single bundle ACL reconstruction was performed in all subjects using a trans-portal technique. Femoral tunnel length was measured intra-operatively. Three-dimensional computed tomography (3D-CT) was taken at pre and post-surgery. The intercondylar notch volume was calculated with a truncated-pyramid shape simulation using the pre-operative 3D-CT image. In the post-operative 3D-CT, the modified quadrant method was used to measure femoral ACL tunnel placement. Results: Femoral tunnel placement was 47.6 ± 10.5% in the high-low (proximal–distal) direction, and 22.6 ± 5.4% in the shallow-deep (anterior–posterior) direction. Femoral tunnel length was 35.3 ± 4.4 cm. Femoral intercondylar notch volume was 8.6 ± 2.1cm3. A significant correlation was found between femoral intercondylar notch volume and high-low (proximal–distal) femoral tunnel placement (Pearson's coefficient correlation: 0.469, p = 0.003). Conclusion: Femoral ACL tunnel placement at a significantly lower level was found in knees with large femoral intercondylar notch volume in the trans-portal technique. For the clinical relevance, although the sample size of this study was limited, surgeons can create femoral ACL tunnel low (distal) in the notch where close to the anatomical ACL footprint in the knees with large femoral intercondylar notch volume. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: Effects of suture preparation on graft contamination remain unknown in anterior cruciate ligament reconstruction (ACLR). This study aimed to evaluate the incidence of allograft contamination at different time points of graft preparation and investigate differences in contamination between different sites of the allografts. Methods: Fourteen hamstring tendon (HT), 9 quadriceps tendon (QT), and 9 bone–patellar tendon–bone (BTB) allografts were harvested, sterilised, and stored following routine procedures. Graft suture preparation was performed with baseball stitching for soft tissue and bone drilling for bone plug. The time was recorded simultaneously. The graft was kept moist in a standard operating room environment for 30 min after the initiation of preparation. The specimens were obtained from the middle and both ends of each graft for culture at three different time points: pre-suturing, post-suturing, and 30 min after the initiation of preparation. A total of 192 specimens were transferred to the microbiology laboratory for culture, identification, and semi-quantitative assessment. Culture results were classified as negative, poor, and abundant based on the extent of growth. Contamination level was recorded as low or high corresponding to culture results of poor or abundant. Results: The duration of suture preparation was 348, 301, and 246 s for HT, QT, and BTB (P = 0.090). The specimens had a positive culture rate of 41/192 (21.4%), of which 21 were from the ends and 20 from the middle. More positive samples with abundant bacterial growth were detected from the ends than from the middles post-suturing (7/8 vs. 1/7, P = 0.010) and at 30 min (6/11 vs. 0/11, P = 0.012). The total graft contamination rate was significantly higher at 30 min (19/32, 59.4%) than pre-suturing (4/32, 15.6%) and post-suturing (9/32, 28.1%) (P < 0.001). The contamination rate with abundant bacterial growth was higher post-suturing (7/32, 21.9%) than pre-suturing (0%). No statistically significant differences were found among the three types of allografts. Conclusion: The contamination rate increases significantly at 30 min compared with pre-suturing and post-suturing. Suture preparation may have introduced the high-level contamination, to which the ends of the graft were more prone than the middle. Therefore, routine prophylactic decontamination after suture preparation should be considered, especially for the ends of the grafts. [ABSTRACT FROM AUTHOR]

Purpose: The posterior tibial slope (PTS) is considered a risk factor for anterior cruciate ligament (ACL) injury. However, the influence of PTS on graft failure following ACL reconstruction remains relatively unknown. Therefore, this systematic review was conducted to investigate whether PTS could be a potential risk factor for graft failure after ACL reconstruction. Methods: PubMed, EMBASE, Cochrane Library, Web of Science, China National Knowledge Infrastructure Database, and Wanfang Database were comprehensively searched from inception to March 31, 2021. Observational studies reporting the associations of medial tibial plateau slope (MTPS) or lateral tibial plateau slope (LTPS) with graft failure after ACL reconstruction were evaluated. Results: Twenty studies involving 12 case–control studies, 4 retrospective studies and 4 cross-sectional studies including 5326 patients met the final inclusion criteria. The high heterogeneity and the characteristics of nonrandomized controlled trials limited data synthesis. Fifteen of the 20 included studies detected a significant association between increased PTS and ACL graft failure, while 5 studies concluded that increased PTS was not associated with ACL graft failure. Ten studies suggested that MTPS is associated with ACL graft failure, and six studies suggested that LTPS is associated with ACL graft failure. The mean MTPS values for nonfailure group ranged from 3.5° ± 2.5° to 14.4° ± 2.8°. For the graft failure group, MTPS ranged from 4.71° ± 2.41° to 17.2° ± 2.2°. The mean LTPS values for nonfailure group ranged from 2.9° ± 2.1° to 11.9° ± 3.0°. For the graft failure group, LTPS ranged from 5.5° ± 3.0° to 13.3° ± 3.0°. The reported PTS values that caused ACL graft failure was greater than 7.4° to 17°. Conclusion: Based on the current clinical evidence, increased PTS is associated with a higher risk of ACL graft failure after ACL reconstruction. Despite various methods of measuring PTS have high reliability, there is still vast disagreement in the actual value of PTS. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: The choice of graft for anterior cruciate ligament (ACL) reconstruction remains controversial. The quadriceps tendon (QT) autograft is a good alternative for ACL reconstruction. However, concerns regarding its use in short-statured patients, related to donor site morbidity, anterior knee pain, or loss of muscle strength remain. This study aimed to compare muscle strength and morbidity between patients with short and normal statures following ACL reconstruction with a QT autograft. Methods: A total of 73 female patients (mean age, 33.8 ± 11.5 years) who underwent primary ACL reconstruction between 2016 and 2019 were included. Patients were categorized into two groups: group S, with a height ≤ 163 cm, and group L, with a height > 163 cm. Muscle strength, harvesting site morbidity, and ACL-return to sport after injury scale (ACL-RSI) were evaluated, with a mean timing of the follow-up of 9.0 ± 2.3 months. Results: The mean quadriceps strength for the isokinetic measurements at 60° and 240° was 65.0% and 74.0% in group S, respectively, and 70.0% and 75.7% in group L, respectively. There was no significant difference in the postoperative muscle strength or mean ACL-RSI (group S, 70.0; group L, 65.9) between the groups. No donor site morbidity was observed in either group. Conclusion: Muscle strength recovery, morbidity, and readiness to return to sports were similar in both groups, which supports the possibility of QT autografts for patients with a small stature. The results of this study may provide useful information for surgeons who are hesitant to perform QT autografts because of patient physique. Level of Evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: To compare the clinical and radiological outcomes in patients undergoing anterior cruciate ligament reconstruction (ACLR) with, or without, LARS augmentation. Methods: One-hundred and thirty-six patients that underwent double-bundle ACLR with (DB Hams/LARS, n = 67), or without (DB Hams, n = 69), LARS augmentation, were assessed clinically and with Magnetic Resonance Imaging (MRI) at a minimum of 7-years post-surgery. Patients were assessed via patient-reported outcome measures (PROMs), KT-1000 (laxity), isokinetic knee extensor and flexor strength and a 4-hop test battery. Limb symmetry indices (LSIs) were calculated. The Whole-Organ Magnetic Resonance Imaging Score (WORMS) evaluated knee status via MRI. Sport participation, secondary operations, ACL re-tears and contralateral ACL tears were reported. Results: No differences (n.s.) were observed in demographics, PROMs, KT-1000 scores or strength and hop LSIs. Normal (< 3 mm side-to-side differences) KT-1000 scores were observed in 64 (92.8%) and 59 (88.1%) of DB Hams and DB Hams/LARS patients, respectively. Comparative rates of satisfaction were reported. Knee flexor strength and hop test LSIs were all ˃95% in both groups, which was 94.2% and 96.7% for knee extensor strength in the DB Hams and DB Hams/LARS cohorts, respectively. While 53 (76.8%) and 52 (77.6%) of the DB Hams and DB Hams/LARS patients had returned to pivoting sports, 42 (60.9%) and 41 (61.2%) were participating in pivoting sports at the minimum 7-year review. No difference (n.s.) was observed in the WORMS (12.3 DB Hams, 16.7 DB Hams/LARS). Of the cohort assessed, 8 (11%) DB Hams and 11 (16%) DB Hams/LARS patients had undergone secondary surgery. In addition to one patient in each group that demonstrated ACL rupture on MRI, an additional cohort of patients were excluded from the current analysis due to prior re-tear (DB Hams n = 6, DB Hams/LARS n = 8) or contralateral ACL tear (DB Hams n = 4, DB Hams/LARS n = 4). Conclusions: Comparable outcomes were observed after double-bundle ACLR using autologous hamstrings with, or without, LARS augmentation. Therefore, while these outcomes do not justify the additional use of synthetic augmentation given the lack of further benefit and additional cost, higher rates of graft failure, synovitis and early osteoarthritic change previously reported were not observed. Level of Evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: Meniscus repair has gained increasing interest over the last two decades as loss of meniscus tissue predisposes to early onset knee arthritis. Although there are many reports of meniscus repair outcome in short-term studies, data on the long-term outcome of meniscus repair are still scarce. The purpose of this meta-analysis was to evaluate the overall failure rate of meniscus repair with a minimum follow-up of 5 years. Additionally, possible factors influencing meniscus repair outcome were assessed. Methods: PubMed and Scopus were searched for studies of the last 20 years reporting on meniscus repair outcome with a minimum follow-up of 5 years. The study was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search terms used for this study were ([meniscus OR meniscal] AND repair). Titles and abstracts were evaluated by two authors independently. Using meta package of R (version 3.6.2), random-effect models were performed to pool failure rates. Subgroup analyses were performed and effect estimates in form of an odds ratio with 95% CIs were established. Results: In total, 12 studies with 864 patients were included. Degenerative tears were excluded in two studies and one study only included traumatic meniscus tears. Other studies did not state whether the cause of meniscus tear was degenerative or traumatic. Studies reporting meniscus repair outcome on root repairs, revision anterior cruciate ligament reconstruction, discoid menisci or ramp lesions were excluded. Revision surgery was used as failure definition in all included studies. The overall failure rate of meniscal repair at a mean follow-up of 86 months was 19.1%. There was no significant difference in meniscus repair outcome when performed in combination with anterior cruciate ligament reconstruction compared to isolated meniscus repair (18.7% vs. 28%; n.s.) or when performed on the lateral meniscus compared to the medial meniscus (19.5% vs. 24.4%; n.s.). There was no significant difference of meniscus repair outcome between vertical/longitudinal tears and bucket-handle tears (n.s.). Thirty-six percent of meniscus repair failures occur after the second postoperative year. The only significant finding was that inside-out repair results in a lower failure rate compared to all-inside repair (5.6% vs. 22.3%; p = 0.009) at 5 years. Conclusion: The overall meniscus repair failure rate remains nineteen percent in long-term studies. The cause of failure is poorly documented, and it remains unclear whether failure of the meniscus repair itself or additional adjacent tears lead to revision surgery. Despite the given technical advantages of all-inside repair devices, this meta-analysis cannot demonstrate superior outcomes compared to inside-out or outside-in repair at 5 years. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of a new remnant preservation technique with a focus on remnant continuity on postoperative femoral and tibial tunnel enlargement after anatomical double-bundle anterior cruciate ligament reconstruction (ACLR).Methods: A total of 150 knees were divided into three groups: Preservation Group (Group P: 49 knees), wherein the remnant continuity remained after tunnel creation; Resection Group (Group R: 47 knees), wherein the remaining remnant was resected, and Absent Group (Group A: 54 knees), wherein the remnant had no femoral attachment before tunnel creation. In Group P, the remnant maintained continuity, and the anteromedial (AM) and posterolateral (PL) bundles were positioned anterior and posterior to the remnant, respectively. Computed tomographic scans were performed at 1 week and 1 year after surgery, and the cross-sectional area of each tunnel aperture was measured. Tunnel enlargement was compared among the three groups by one-way analysis of variance (ANOVA) and the Bonferroni test. Univariate and multivariate logistic analyses were performed to identify the risk factors for tunnel enlargement in demographic and radiographic data.Result: For femoral AM tunnels, the tunnel enlargement of Group P was significantly smaller than Groups R and A (p < 0.001), femoral PL (p < 0.001 vs. R and A), tibial AM (p < 0.001 vs. R, 0.002 vs. A), and tibial PL (p < 0.001 vs. R, 0.002 vs. A). There was no significant difference between Groups R and A. Multivariate logistic analysis showed that remnant preservation was a significant factor in reducing tunnel enlargement in the femoral AM, femoral PL, tibial AM, and tibial PL.Conclusion: The new remnant-preserving anatomical double-bundle ACLR, which preserves the continuity of the remnant, prevented all bone tunnel enlargement at 1 year postoperatively.Level Of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect that femoral and tibial tunnel positions have on long-term reported and clinical outcome and to identify a safe zone based on favourable outcome.Methods: Seventy-eight patients from a previous randomised controlled trial were included and were followed with a mean follow-up of 11.4 years. All patients had primary trans-tibial anterior cruciate ligament reconstruction performed. The femoral and tibial tunnel positions were visualised and translated in percentages with three-dimensional computed tomography post-operatively. There were 3 separate outcome variables: patient-reported outcome measured with the IKDC Subjective Knee Form, overall failure, and radiographic osteoarthritis. The correlation between tunnel aperture positions and outcome was determined with multivariate regression. The area with best outcome was defined as the safe zone and was determined with Youden's index in conjunction with receiver operating characteristics.Results: No significant relationship was found between tunnel aperture positions and IKDC Subjective Knee Form at 10-year follow-up. The posterior-to-anterior femoral tunnel aperture position parallel to Blumensaat line showed a significant relationship (p = 0.03) to overall failure at 10-year follow-up. The mean posterior-to-anterior tunnel position of the group that did not fail was 37.7% compared to 44.1% in the overall failure group. Femoral tunnel apertures placed further anteriorly had more overall failures at long-term. The cut-off point lies at 35.0% from posterior-to-anterior parallel to Blumensaat. Of the 16 overall failures, 15 (93.8%) were placed further anteriorly than the cut-off point. No significant relationship was found between tunnel aperture positions and radiographic osteoarthritis.Conclusion: Femoral and tibial tunnel positions were not associated with long-term patient-reported outcome and radiographic osteoarthritis. Long-term overall failure was more frequently seen in patients with a more anteriorly placed femoral tunnel. This study identified a safe zone located at the most posterior 35% of the femoral condyle parallel to Blumensaat. This knowledge offers guidance to surgeons to operate more precisely and accurately and reconstruct a long-lasting graft.Level Of Evidence: Level III. [ABSTRACT FROM AUTHOR]

Purpose: Quadriceps strength deficits following anterior cruciate ligament reconstruction (ACLR) are linked to altered lower extremity biomechanics, tibiofemoral joint (TFJ) space narrowing and cartilage composition changes. It is unknown, however, if quadriceps strength is associated with cartilage volume in the early years following ACLR prior to the onset of posttraumatic osteoarthritis (OA) development. The purpose of this cross-sectional study was to examine the relationship between quadriceps muscle strength (peak and across the functional range of knee flexion) and cartilage volume at ~ 2 years following ACLR and determine the influence of concomitant meniscal pathology.Methods: The involved limb of 51 ACLR participants (31 isolated ACLR; 20 combined meniscal pathology) aged 18-40 years were tested at 2.4 ± 0.4 years post-surgery. Isokinetic knee extension torque generated in 10° intervals between 60° and 10° knee flexion (i.e. 60°-50°, 50°-40°, 40°-30°, 30°-20°, 20°-10°) together with peak extension torque were measured. Tibial and patellar cartilage volumes were measured using magnetic resonance imaging (MRI). The relationships between peak and angle-specific knee extension torque and MRI-derived cartilage volumes were evaluated using multiple linear regression.Results: In ACLR participants with and without meniscal pathology, higher knee extension torques at 60°-50° and 50°-40° knee flexion were negatively associated with medial tibial cartilage volume (p < 0.05). No significant associations were identified between peak concentric or angle-specific knee extension torques and patellar cartilage volume.Conclusion: Higher quadriceps strength at knee flexion angles of 60°-40° was associated with lower cartilage volume on the medial tibia ~ 2 years following ACLR with and without concomitant meniscal injury. Regaining quadriceps strength across important functional ranges of knee flexion after ACLR may reduce the likelihood of developing early TFJ cartilage degenerative changes.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: To determine specific return to sports (RTS) and return to work (RTW) rates of patients with septic arthritis following anterior cruciate ligament reconstruction (ACLR), and to assess for factors associated with a diminished postoperative return to physical activity after successful eradication of the infection. Methods: In this study, patients who were treated for postoperative septic arthritis of the knee following anterior cruciate ligament reconstruction between 2006 and 2018 were evaluated at a minimum follow-up (FU) of 2 years. Patients' outcomes were retrospectively analyzed using standardized patient-reported outcome scores including the Lysholm score and the subjective IKDC score, as well as return to sports and return to work questionnaires to assess for the types, number, and frequency of sports performed pre- and postoperatively and to evaluate for potential occupational changes due to septic arthritis following ACLR. To assess for the signifiance of the graft at follow-up, outcomes were compared between patients with a functioning graft at FU and those without, as well as between patients with initial graft retention and those with graft removal and consecutive revision ACLR. Results: Out of 44 patients eligible for inclusion, 38 (86%) patients at a mean age of 36.2 ± 10.3 years were enrolled in this study. At a mean follow-up of 60.3 ± 39.9 months, the Lysholm score and the subjective IKDC score reached 80.0 ± 15.1 and 78.2 ± 16.6 points, respectively. The presence of a graft at FU yielded statistically superior results only on the IKDC score (p = 0.014). There were no statistically significant differences on the Lysholm score (n.s.) or on the IKDC score (n.s.) between patients with initial graft retention and those with initial removal who had undergone revision ACLR. All of the included 38 patients were able to return to sports at a median time of 8 (6–16) months after their last surgical intervention. Among patients who performed pivoting sports prior to their injury, 23 (62.2%) returned to at least one pivoting sport postoperatively. Overall, ten patients (26.3%) returned to all their previous sports at their previous frequency. The presence of a graft at FU resulted in a significantly higher RTS rate (p = 0.010). Comparing patients with initial graft retention and those with graft removal and consecutive revision ACLR, there was no statistically significant difference concerning the RTS rate (n.s.). Thirty-one patients (83.8%) were able to return to their previous work. Conclusion: Successful eradication of septic arthritis following anterior cruciate ligament reconstruction allows for a postoperative return to sports and a return to work particularly among patients with ACL-sufficient knees. However, the patients' expectations should be managed carefully, as overall return rates at the pre-injury frequency are relatively low. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: The Anterior cruciate ligament (ACL) remnant has been pointed out as a ligamentization enhancer. Nonetheless, the remaining tissue can be functional if it still provides some stability or nonfunctional. This study intends to compare the clinical results and knee stability of functional vs. nonfunctional remnant preservation ACL reconstruction (ACLR). Methods: One hundred and seventy-five patients with ACL injuries were included and underwent remnant preservation ACLR. They were divided into two groups accordingly to remnant tissue functionality: functional (Group F) and nonfunctional (Group NF). Primary outcome was defined as patient reported outcomes measured with Lysholm, IKDC and Tegner continuous scales and improvements. Secondary outcomes comprised of Lachman test, anterior drawer test, pivot shift test, extension and flexion deficit, graft coverage by remnant preserved tissue and failure rate (persistent instability or new ACL lesion). Menisci lesions, cartilage lesions and time to surgery were also recorded for each group. Results: One hundred and forty-four patients were available at a mean of 30.2 ± 10.1 months: 69 Functional and 75 Nonfunctional. Lysholm, IKDC and Tegner functional outcomes demonstrated no difference between the groups, Functional compared to Nonfunctional: 88.4 ± 10.5 vs. 92.2 ± 4.9, n.s. and 83.2 ± 11.3 vs. 87 ± 5.3, n.s. and 6 (5–10) vs. 6 (5–9), n.s., respectively. Lysholm and IKDC functional outcomes improvements demonstrated differences between the groups: Functional compared to Nonfunctional (39.3 ± 9.4 vs. 42.3 ± 7.4, p = 0.014 and 37.7 ± 10 vs. 41.0 ± 6.6, p = 0.032); however, they were not clinically significant. Functional group showed more stability on physical examination pre- and post-operatively (p < 0.001, p < 0.001). There was no difference regarding extension deficit (n.s.); however, functional group had more flexion deficit (p = 0.02). Nonfunctional group had better graft coverage (p = 0.001). There was no difference regarding failure rate: 4% vs. 9%, (n.s.). Conclusion: Both remnant preservation ACLR techniques were able to achieve satisfactory functional outcomes. A functional remnant was not related to improved functional outcomes in comparison to a nonfunctional remnant; however, it was related to less laxity pre and postoperatively and inferior graft coverage. Level of evidence: II. [ABSTRACT FROM AUTHOR]

PurposeAnterior cruciate ligament (ACL) rupture is increasingly common in adolescents. Time between ACL rupture and surgical reconstruction, surgical wait time, is related to concurrent meniscal tear incidence and possibly tear pattern. This study defines the relationship between meniscal tear characteristics and surgical wait time in adolescents with ACL rupture.MethodsOne-hundred and twenty-one consecutive adolescent (median age 16.1 years, range 9-19 years) ACL rupture patients undergoing primary ACL reconstruction were studied. All had documented surgical wait time, preoperative and 6-month post-operative outcome (Lysholm and pedi-IKDC) scores, and intraoperative meniscus tear characteristics. Meniscal tear severity was graded according to the Lawrence and Anderson system: non-surgical: grade 1; reparable: grade 2-3; irreparable: grade 4-5. Significant tears were defined as at least grade 2.ResultsAverage age at surgery was 16.1 years. 48.7 % had surgical wait time greater than 6 months. 42.5 % of menisci were torn. With surgical wait time 6 months, medial tear incidence increased (50 vs 21 %, p 6 months. Public insurance was a risk factor for longer surgical wait time and meniscus tear.

Purpose: The purpose of this study was to prospectively evaluate the clinical outcomes following anatomical rectangular tunnel anterior cruciate ligament (ACL) reconstruction with a bone–patellar tendon–bone (BTB) graft using an adjustable-length femoral cortical fixation device with enough patients and a high follow-up rate. Methods: This study included 125 patients who underwent anatomical rectangular tunnel ACL reconstruction with a BTB graft. A BTB TightRope® was used for femoral graft fixation. Clinical evaluations were performed more than 2 years after surgery using the International Knee Documentation Committee (IKDC) Form. Patients interviewed by telephone were only subjectively evaluated. The side-to-side difference in anterior laxity at a manual maximum force was measured using the KT-2000 Arthrometer®. Results: Among the 125 patients, 99 were ultimately included and 26 were lost to follow-up (follow-up rate: 79%). Eight patients had re-tear (re-tear rate: 8%) and six patients had ACL injuries to the contralateral knee. Three patients did not follow our rehabilitation programme. One patient suffered septic arthritis. These 18 patients were considered ineligible for clinical evaluations. Therefore, clinical evaluations were performed in 81 of the 99 patients (64 were available for direct follow-up and 17 were available for a telephone interview). The follow-up period was 30 ± 10 months (range 24–68 months). According to the IKDC subjective assessment, 48 (59%) and 33 (41%) knees were graded as normal and nearly normal, respectively. A loss of extension (3°–5°) was observed in five patients (8%), whereas one patient (2%) exhibited a loss of flexion (3°–5°). The Lachman test was negative in 63 patients (98%). The pivot shift test was negative in 59 patients (92%). The side-to-side difference in KT value was 0.4 ± 0.7 mm (range − 1–4 mm). Conclusion: Anatomical rectangular tunnel ACL reconstruction with a BTB graft using an adjustable-length femoral cortical fixation device provided excellent clinical outcomes both subjectively and objectively more than 2 years after surgery, whereas 8 of the 99 patients had re-tear of the graft. The adjustable-length femoral cortical fixation device could be safely used in anatomical rectangular tunnel ACL reconstruction with a BTB graft. Level of evidence: III [ABSTRACT FROM AUTHOR]

Purpose: To compare patient reported outcomes and functional knee recovery following anterior cruciate ligament (ACL) reconstruction using either a quadriceps tendon (QT) or hamstring tendon (HT) autograft. Methods: Thirty-five QT patients (age 20; range 15–34 years) participated in this study and were matched for gender, age and pre-injury activity level to 70 HT (age 20; range 15–32 years) patients. The following assessments were performed at 6 and 12 months post-operatively; standardized patient-reported outcome measures (IKDC, KOOS-QOL, ACL-RSI, Marx activity, anterior knee pain), knee range of motion (passive and active), anterior knee laxity, hop tests (single and triple crossover hop for distance), and isokinetic strength of the knee extensors and flexors. All dependent variables were analysed using a two-way mixed ANOVA model, with within (Time; 6 and 12 months) and between-subject (Graft; QT and HT) factors. Results: Patient reported outcome measures and hop performance improved between 6 and 12 months (p < 0.001), however no significant differences in either patient-reported outcomes or hop performance were found between the two grafts. Isokinetic strength testing showed both groups improved their peak knee extensor strength in the operated limb between 6 and 12 months (p < 0.001), but the QT group had significantly lower knee extensor strength symmetry at both time points compared to HT at 60 deg/s (p < 0.001) and 180 deg/s (p < 0.01). In contrast, the QT group had significantly greater knee flexor strength symmetry at both time points compared to HT at 60 deg/s (p < 0.01) and 180 deg/s (p = 0.01), but knee flexor strength limb symmetry did not significantly improve over time in either group. Conclusion: Recovery of knee function following either QT or HT ACL reconstruction continues between 6 and 12 months after surgery. However, knee extensor strength deficits in the QT group and knee flexor strength deficits in the HT persisted at 12 months. This may have implications for decisions regarding return to sport. Level of evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: To translate and culturally adapt the anterior cruciate ligament-return to sport after injury (ACL-RSI) scale into Italian (ACL-RSI(IT)) and examine and evaluate the psychometric properties of the Italian version in individuals who have undergone anterior cruciate ligament (ACL) reconstruction. Methods: The ACL-RSI was forward and back translated, culturally adapted and validated one hundred and twenty nine Italian individuals who had undergone ACL reconstruction (94 males, 35 females; age 28 ± 9 years). All patients completed the translated ACL-RSI, Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee subjective knee form (IKDC), Tampa Scale of Kinesiophobia (TSK) and the 12-item short form health survey (SF-12). We then analysed the internal consistency, reliability and validity of the newly formed ACLRSI (IT). Results: The ACL- RSI(IT) showed excellent internal consistency (Cronbach's alpha 0.94) and was significantly correlated with the KOOS 'quality of life' (r = 0.61, p < 0.00001), 'symptoms' (r = 0.34, p < 0.00001), 'pain' (r = 0.44, p < 0.00001), and 'sports' (r = 0.40, p < 0.00001) subscales. The ACL-RSI(IT) also correlated significantly with the IKDC (r = 0.34, p < 0.001), TSK (r = − 0.48, p < 0.00001) and SF-12 (r = − 0.40, p < 0.0001) scores. Conclusion: The Italian version of the ACL-RSI scale was valid, discriminant, consistent and reliable in patients who had undergone ACL reconstruction. This score could be useful to evaluate the effect of psychological factors on return to sport following ACL surgery. Level of evidence: II. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the risk factors for prolonged joint effusion in patients undergoing double-bundle anterior cruciate ligament reconstruction (ACLR). Methods: In total, 160 patients who underwent primary ACLR using autograft hamstring between 2015 and 2018 were retrospectively reviewed. Joint effusion was defined as any grade ≥ 2 (range, 0–3) according to the MRI Osteoarthritis Knee Score (MOAKS). Univariate and multivariate logistic regression analyses were performed. Results: The median age of the patients was 25 years (range 14–68 years) at the time of the surgery; there were 89 women and 71 men. At 1 year, 46 (28.8%) patients experienced knee joint effusion, as defined by the MOAKS. Univariate analysis revealed that age, preoperative Kellgren–Lawrence (K–L) grade, and joint effusion at 6 months were significantly associated with joint effusion at 1 year. In the multivariate analysis, joint effusion at 6 months was significantly associated with joint effusion at 1 year (odds ratio, 68.0; 95% confidence interval, 22.1–209.4). No significant difference in the Lysholm scores was observed between patients with and without joint effusion at 1 year (n.s.). Conclusions: Joint effusion at 6 months was significantly associated with joint effusion 1 year after ACLR. Level of evidence: III. [ABSTRACT FROM AUTHOR]

PurposeThe goal of this paper is to compare patient factors, intra-operative findings, and surgical techniques between patients followed in large cohorts in France, Norway, and North America.MethodsData collected on 2,286 patients undergoing revision anterior cruciate ligament reconstruction (ACLR) were obtained. These data included 1,216 patients enrolled in the Multicenter ACL Revision Study (MARS) in North America, 793 patients undergoing revision ACLR and recorded in the Norwegian Knee Ligament Registry (NKLR), and 277 patients recorded in the revision ACL database of the Société Française d'Arthroscopie (SFA) in France. Data collected from each database included patient demographics (age, sex, height, and weight), graft choice and reason for failure of the primary ACLR, time from primary to revision ACLR, pre-revision patient-reported outcome scores (Knee Injury and Osteoarthritis Outcome Score, subjective International Knee Documentation Committee), associated intra-articular findings and treatments at revision, and graft choice for revision reconstruction.ResultsPatient demographics in the three databases were relatively similar. Graft choice for primary and revision ACLR varied significantly, with more allografts used in the MARS cohort. Hamstring autograft was favoured in the NKRL, while bone-patellar tendon-bone autograft was most common in the SFA cohort. Reasons for failure of the primary ACLR were comparable, with recurrent trauma noted in 46-56 % of patients in each of the three cohorts. Technical error was cited in 44-51 % of patients in the MARS and SFA cohorts, but was not clearly elucidated in the NKLR cohort. Biologic failure of the primary graft was more common in the MARS cohort. Differences in associated intra-articular findings were noted at the time of revision ACLR, with significantly more high-grade cartilage lesions noted in the MARS group.ConclusionsSignificant differences exist between patient populations followed in revision ACL cohorts throughout the world that should be considered when applying findings from such cohorts to different patient populations.Level of evidenceRetrospective comparative study, Level III.