Search

Background: Patellar dislocation is a common knee injury and up to 35% of those who dislocate the patella can develop recurrent patellar instability. In the setting of recurrent instability, medial patellofemoral ligament (MPFL) reconstruction is often performed to restore knee stability. There has been recent interest in patient and surgical factors that influence outcomes of MPFL reconstruction. Much of the previous work has focused on influences of anatomic measures; however, patients and injury characteristics may also impact surgical outcomes. Hypothesis: Patients who experience >2 patellar dislocations before MPFL reconstruction would demonstrate poorer patient-reported outcomes (PROs) compared with those with ≤2 previous dislocations. Study design: Cohort study; Level of evidence, 3. Methods: Records were reviewed to identify patients who underwent MPFL reconstruction at a single institution between 2008 and 2016. Patients who underwent concomitant tibial tubercle osteotomy or fixation of an osteochondral fracture were excluded. Patient demographics (age, sex, body mass index [BMI]), number of previous patellar dislocations, and patient anatomic measures (Caton-Deschamps index (CDI), tibial tubercle-trochlear groove (TT-TG) distance, and trochlear sulcus angle) were collected. PROs were assessed with Norwich Patellar Instability score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Marx activity score. Outcomes of patients with >2 patellar dislocations were compared with those with ≤2 dislocations using multiple linear regression analysis. Results: Medical record review revealed 160 patients who underwent isolated MPFL reconstruction (71 with ≥2 dislocations and 89 with >2 dislocations); 95 patients (59%) completed PROs at a median follow-up of 4.6 years postoperation (range, 1.0-12.6 years). Patients with ≥2 dislocations were younger (≥2 dislocations: 20.7 ± 7.3 years, >2 dislocations: 28.5 ± 10.0 years; P <.001), although there were no other differences in demographics or radiographic anatomic measures between groups. Adjusting for age, sex, BMI, CDI, TT-TG distance, and trochlear sulcus angle, patients with >2 dislocations had 13.7 points lower KOOS-Pain (P =.003), 8.3 points lower KOOS-Activities of Daily Living (P =.025), 18.2 points lower KOOS-Sports and Recreation (P =.009), and 19.8 points lower KOOS-Knee-Related Quality of Life (P =.008) subscale scores than patients with ≤2 dislocations. No significant differences in KOOS symptoms subscale, Norwich Patellar Instability, or Marx score were noted between groups. Conclusion: Patients with >2 patellar dislocations before MPFL reconstruction exhibited poorer PROs at a median of 4.8 years postoperation compared with those who had ≤2 dislocations before surgery, when adjusting for age, sex, BMI, CDI, TT-TG distance, and trochlear sulcus angle. [ABSTRACT FROM AUTHOR]

Introduction: Anterior cruciate ligament (ACL) rupture is a debilitating condition and often requires surgery to restore joint stability. Common autografts used for reconstruction include patella tendon and hamstring tendons. The primary aim of this study was to evaluate the early to mid-term clinical outcomes of ACL reconstruction using validated patient-reported outcome measures (PROMs). The secondary aim was to compare clinical outcomes between patella tendon and hamstring tendon autografts. The tertiary aim was to compare clinical outcomes between males and females. Methods: Patients with an ACL rupture were evaluated before and after surgery using PROM scores which included Lysholm, Tegner, International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS), Short Form-12 Item (SF-12) and EQ-5D-5L. Results: A total of 87 patients were included in the study. All PROM scores significantly improved following surgery (p < 0.001) at a mean follow-up time of 28 months (range 12 to 88 months). The patella tendon subgroup (n = 27) had superior post-operative results as compared to the hamstring tendon subgroup (n = 60) for KOOS sport and recreation (p = 0.005), KOOS quality of life (p = 0.025), KOOS overall (p = 0.026), Tegner (p = 0.046) and IKDC (p = 0.021) scores. There was no significant difference of PROM scores between males (n = 60) and females (n = 27) (p > 0.05). Conclusions: ACL reconstruction significantly improves clinical outcomes for patients with symptomatic instability consequent to ACL rupture. Overall, patella tendon autograft resulted in better clinical outcomes as compared to hamstring tendon autograft following surgery. Gender did not influence clinical outcome following ACL reconstruction. [ABSTRACT FROM AUTHOR]

Ultrasound shear wave elastography (SWE) is a tool that can be utilized to assess biomechanical properties of tendons. Anisotropy, an ultrasound imaging artifact has been commonly cited as a potential source of error in the accuracy and reproducibility of SWE. The aim of the study was to assess reproducibility in performing SWE of patella tendons and differences in SWE and anisotropy between normal patella tendons and patellar tendinopathy. After obtaining the Institutional Review Board approval and written informed consent, we prospectively measured the shear wave velocity (SWV) of patella tendons with and without tendinopathy in 25 volunteers. SWVs were measured in three anatomic planes: longitudinal, perpendicular transverse, and tilted transverse with the probe tilted 15–30° from the perpendicular transverse plane by three operators with varied levels of experience. Anisotropy coefficient (A) was calculated by formula of A = (SWV Longitudinal − SWV Transverse) / SWV Transverse. Differences in SWV and anisotropy coefficient between normal tendons and tendons with tendinopathy were significant (p < 0.05). The intra- and inter-observer reproducibility in performing SWE were moderate to good (intraclass correlation coefficient: 0.81–0.95). The mean difference of 95% Bland-Altman limits of agreement for measuring tendon SWV ranged −0.08 to 0.41 (upper 0.08 to 1.14, lower −1.22 to −0.22) between senior and junior operators. The results of this study suggest that SWE and anisotropy coefficient are feasible tools to differentiate patellar tendinopathy from normal patella tendons. The reproducibility of performing SWE of patella tendons is moderate to good. • Intra- and inter-observer reproducibility of SWE performed by junior and senior observers was shown to be moderate to good. • SWE and anisotropy coefficient were shown to be feasible tools to differentiate patella tendons with and without tendinopathy. • Average SWV significantly decreased in patellar tendons with tendinopathy. [ABSTRACT FROM AUTHOR]

The patellar tendon is an integral part of the knee extensor mechanism and has been historically described as a single tendon. A doubled patellar tendon is an exceedingly rare finding. We present a case of a crossed doubled patellar tendon in a 70-year-old male with a history of right knee pain, which to our knowledge has only been reported once before in the literature. The presence of a doubled patellar tendon has a potential influence on surgical planning and in the etiology of anterior knee pain.

IntroductionLesions of the quadriceps or patellar tendon after total knee arthroplasty (TKA) are a rare but serious complication which, if left untreated, can lead to loss of function of the knee joint. While acute and subacute extensor mechanism disruptions may have several causes, chronic deficiencies are often related to multiple prior revision surgeries for joint infection or aseptic TKA failure. Up to date, biological allograft reconstruction showed unsatisfying results. The use of a monofilament polypropylene mesh is a promising approach for this pathological condition. The aim of the present study was to evaluate clinical, functional and patient reported outcomes of this procedure in patients with chronic extensor mechanism deficiency.Materials and MethodsTwenty-eight patients with chronic extensor mechanism deficiency (quadriceps tendon rupture n = 9, patellar tendon rupture n = 19) after TKA were included in this retrospective study. None of the patients were lost to follow-up. Surgical reconstruction was performed at one institution between 2014 and 2020 with a monofilament polypropylene mesh (Marlex Mesh, Bard, Murray Hill, USA). The mean age at the time of surgery was 69 years. Patients presented with a mean BMI of 33 kg/m2. The mean follow-up period was 23 months.ResultsThe 2-year survivorship free of mesh revision was 89% [95% confidence interval (CI): 75% to 100%]. Three patients (11%) had to undergo revision because of mechanical mesh failure and received another polypropylene mesh. No further revisions were performed thereafter. Flexion was 87° (range, 30–120°) on average. The majority of patients (75%, 21/28) had a full active extension. The mean active extension lag after surgery was 4 degrees (range, 0–30°).DiscussionWe observed a substantial improvement of extensor mechanism function. The majority of patients had full extension and showed good clinical results. A failure rate of over 50% has been published for alternative procedures. Thus, the use of the described augmentation technique represents a reasonable treatment option for chronic extensor mechanism disruptions of the patellar tendon as well as the quadriceps tendon after total knee arthroplasty. However, there might be a potentially higher risk for infection persistence in periprosthetic joint infection cases due to the presence of a foreign material.

Abstract Purpose To evaluate if High-volume Image-guided Injection (HVIGI)-treatment for chronic Patellar tendinopathy (PT) improve function and reduce pain at 16-months follow-up. Methods Patients with resistant PT who failed to improve after a three-month eccentric loading program were included in the study. Maximal tendon thickness was assessed with ultrasound. All patients were injected with 10 mL of 0.5% Marcaine, 0.5 mL Triamcinolonacetonid (40 mg/mL) and 40 mL of 0.9% NaCl saline solution under real-time ultrasound-guidance and high pressure. All outcome measures were recorded at baseline and at 16 months. A standardised Heavy Slow Resistance rehabilitation protocol was prescribed after HVIGI-treatment. Clinical outcome was assessed with the Victorian Institute of Sports Assessment-Patella tendon questionnaire (VISA-P) and statistically analyses were performed. Results The study included 28 single treatment HVIGI procedures in PT in 23 patients (19 men, 4 women) with a mean age of 30.3 (range 19–52). The mean duration of symptoms before HVIGI was 33 months. The baseline VISA-P score of 43 ± 17 (range 15–76) improved to 76 ± 16 (range 42–95) after 16 months (p

A stress-avulsion fracture of the inferior pole of the patella is rare. We report a case of a 65-year-old woman who underwent open reduction and internal fixation for a transverse fracture of the patella using cannulated screws inserted from the inferior pole of the patella. Subsequently, the patient developed an avulsion fracture of the inferior pole of the patella due to a stress riser from the prominent screw head. The avulsion fracture was treated with open repair and augmentation using a cerclage wire, and the stress riser was eliminated by burying the screw head into the bone. The outcomes were satisfactory. Preventing implant-related stress risers during internal fixation of fractures requires diligent surgical techniques., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Rajeev et al.)

Objectives: Autologous tenocyte implantation (OrthoATI™) therapy has demonstrated efficacy in treating patients with tendinopathy at various anatomical sites. This study evaluates the effect of patient age, gender, and tendon biopsy site on morphology, growth, and gene expression of autologous tendon cells used to treat chronic tendinopathy., Methods: Patients undergoing OrthoATI™ for tendinopathies between 2020 and 2022 were initially treated by biopsies taken from patella tendon (PT) or palmaris longus tendon (PL). The biopsies were sent to a Good Manufacturing Practice (GMP) cell laboratory where tendon cells were isolated, cultured, and expanded for four to six weeks. Cell morphology was assessed using phase contrast microscopy. Droplet digital PCR (ddPCR) was utilized for gene expression analysis. Dichotomous results were compared between groups using x 2 or Fisher's exact tests with no adjustment for multiple comparisons. The nonparametric Mann-Whitney U and Kruskal-Wallis tests were utilized for the sex and age (<35y, 35-44y, 45-54y, >55y) analyses, respectively. All analyses were performed using IBM SPSS v27, and a two-tailed P-value of <0.05 was considered statistically significant., Results: 149 patients were included in the analysis. The PT was biopsied in 63 patients, and PL in 86 patients. There were no observer effects for age and gender between the PT and PL groups. There was no statistical significance between the PT and PL tendons for cell morphology, average cell population doubling time (PDT) (PT 83.9 vs PL 82.7 ​h, p ​= ​0.482), cellular yield (PT 16.2 vs PL 15.2 ​× ​10 6 , p ​= ​0.099), and cell viability (PT 98.7 vs PL 99.0%, p ​= ​0.277). Additionally, ddPCR analyses showed no statistical significance found in tenogenic gene expression, including collagen type I (COL1, p ​= ​0.86), tenomodulin (TNMD, p ​= ​0.837) and scleraxis (SCX, p ​= ​0.331) between PT- and PL-derived tendon cells. An age stratification analysis found no effect on growth and gene expression. COL1 was found to be higher in males when compared to females (P ​< ​0.001), but otherwise no difference was seen in growth and gene expression in the gender analysis. No postbiopsy clinical complications were reported for either group., Conclusion: This study has shown that the growth and bioactivities of tendon cells from tendon biopsies for OrthoATI™ are not affected by tendon donor site and age., Level of Evidence: IV., Competing Interests: Declaration of competing interest MHZ & AW hold shares of Orthocell Ltd., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Patellar tendinopathy (PT) is a chronic, degenerative form of tendinitis commonly affecting young, active individuals. Numerous nonsurgical treatments exist, of which platelet-rich plasma (PRP) is a frontrunner. However, heterogeneity among various PRP preparation techniques results in a large variation in treatment efficacy. This review and meta-analysis aims to investigate the effect of PRP centrifugation factors, specifically centrifuge speed and duration, on functional outcomes in patients with PT. A systematic search of the literature was performed in April 2024 on Medline and Embase. Articles involving the use of PRP in the treatment of PT were included. The risk of bias was assessed using the Risk of Bias 2 (RoB 2; the Cochrane Collaboration, England, UK) and Risk of Bias in Non-randomised Studies of Intervention (ROBINS-I; the Cochrane Collaboration, England, UK) tools. Comparative meta-analysis between the different centrifugation speeds and the different centrifugation durations was performed on articles reporting Victorian Institute of Sports Assessment - Patellar tendon (VISA-P) and visual analogue scale (VAS) scores for PT. Seventeen studies consisting of 360 participants were included in the analysis. The mean follow-up duration was 13.2 months (95% CI: 8.81 to 17.7). The mean VAS reduction was 3.85 (95% CI: -4.63 to -3.08; P < 0.01). VISA-P scores improved by 32.03 (95% CI: 24.29 to 39.78; P < 0.01). There were no significant differences between centrifuge speeds for VAS (P = 0.17) and VISA-P (P = 0.18) and between centrifuge durations for VAS (P = 0.25) and VISA-P (P = 0.27). Centrifuge speed and duration and number of centrifuge cycles did not show any significant differences in patient outcomes. There were no significant differences observed in outcomes for the different preparations of PRP. There remains a need for further high-quality RCTs using standardized PRP preparations with long-term follow-up for the development of a consensus method of PRP preparation for the treatment of PT., Competing Interests: Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Zhang et al.)

Ruptures of the extensor mechanism of the knee are serious injuries requiring prompt diagnosis and treatment. They can be divided into soft tissue and bony causes. Soft tissue tendon injuries can be either partial or complete. Rupture of the quadriceps tendon is an uncommon injury and is more frequent in patients over the age of 40 years. Patella tendon ruptures are even rarer and are more frequent in patients under the age of 40 years. Causes can be direct or indirect. Complete ruptures of the quadriceps tendon or patella tendon benefit from early surgical management, while partial ruptures may be managed non-operatively. This article gives an overview of the presentation, assessment and management of soft tissue extensor mechanism tendon ruptures for core surgical, acute care common stem and emergency medicine trainees. [ABSTRACT FROM AUTHOR]

To determine normal temperatures over the Patella tendon over eleven weeks. A prospective cohort study with eleven weeks of observation. University's Human Biomechanics and Physiology Laboratory. Male or female collegiate runners running at least 25 miles per week who did not report pain in the region of the Patella tendon over 11 weeks of data collection. Thermal images taken at the same time and day of the week, were used to measure the temperature of the skin over the Patella tendon. Eighteen athletes were eligible for analysis. The mean temperature of the Patella tendon was 30.13 °C (SD = 1.51 °C). Patella tendon temperature changes over time were insignificant (right p = 0.66, left p = 0.90) with ICC right = 0.92, left = 0.94. Mean temperature difference side to side was 0.14 °C (SD = 0.60 °C). Mixed-model Linear regression for mean temperature differences found the effect of (i) time (t = 0.39, p = 0.70, df = 361) and (ii) side (t = −0.89, p = 0.38, df = 361) to be insignificant. This is the first report of normal thermal profiles of collegiate runners over an extended period. Temperature variation above 1.20 °C may represent an abnormal asymmetry in the running population. Variations in Patella tendon temperatures left to right, and over time were not significant. • Mean temperature of the Patella tendon in non-injured collegiate athletes was 30.13 °C. • Patella tendon temperature changes over time were insignificant. • Mean temperature difference side to side was 0.14 °C. • Temperature variation above 1.20 °C may represent an abnormal asymmetry. [ABSTRACT FROM AUTHOR]

The purposes of this study were to compare the elasticity of tendon and aponeurosis in human knee extensors and ankle plantar flexors in vivo and to examine whether the maximal strain of tendon was correlated to that of aponeurosis. The elongation of tendon and aponeurosis during isometric knee extension (n = 23) and ankle plantar flexion (n = 22), respectively, were determined using a real-time ultrasonic apparatus, while the participants performed ramp isometric contractions up to voluntary maximum. To calculate the strain values from the measured elongation, we measured the respective length of tendon and aponeurosis. For the knee extensors, the maximal strain of aponeurosis (12.1 ± 2.8%) was significantly greater than that of the patella tendon (8.3 ± 2.4%), p < 0.001. On the contrary, the maximal strain of Achilles tendon (5.9 ± 1.4%) was significantly greater than that of aponeurosis in ankle plantar flexors (2.7 ± 1.4%), p < 0.001. Furthermore, for both knee extensors and ankle plantar flexors there was no significant correlation between maximal strain of tendon and aponeurosis. These results would be important for understanding the different roles of tendon and aponeurosis during human movements and for more accurate muscle modeling. [ABSTRACT FROM AUTHOR]

Achondroplasia is a genetic mutation of fibroblast growth factor receptor resulting in impaired growth plate development in long bones due to lower collagen turnover. Despite the characteristic shorter stature and lower strength in Achondroplasic groups, little is known of the tendon mechanical properties under loading. The aim of this study was therefore to conduct a between measure design of patella tendon (PT) mechanical properties (stress, strain, stiffness and Young's Modulus) in 10 men with Achondroplasia (22 ± 3 years) and 17 male controls (22 ± 2 years). PT mechanical properties were measured during isometric maximal voluntary contraction (iMVC) of the knee extensors using ultrasonography. The Achondroplasic group produced 54% less stress at iMVC than controls (29.4 ± 8.0 v 64.5 ± 14.0 MPa, P < 0.001, d = 3.12). Maximal excursion of the Achondroplasic PT was 22% less than controls at iMVC (7.4 ± 2.1 v 5.5 ± 1.7 mm, P < 0.001, d = 0.99), but there was no difference in strain between groups (13 ± 4 v 13 ± 3%, P > 0.05). Achondroplasic PT were 47% less stiff (748 ± 93 v 1418 ± 101 N·mm−1, P < 0.001, d = 6.89) and had a 51% lower Young's modulus (0.39 ± 0.09 v 0.77 ± 0.14 GPa, P < 0.001, d = 3.46) than controls at iMVC. Achondroplasic PT are indeed more compliant than controls which may contribute to lower relative force production. The causes of higher Achondroplasic PT compliance are unclear but are likely due to the collagen related genetic mutation which causes Achondroplasia.

Achondroplasia is a genetic mutation of fibroblast growth factor receptor resulting in impaired growth plate development in long bones due to lower collagen turnover. Despite the characteristic shorter stature and lower strength in Achondroplasic groups, little is known of the tendon mechanical properties under loading. The aim of this study was therefore to conduct a between measure design of patella tendon (PT) mechanical properties (stress, strain, stiffness and Young's Modulus) in 10 men with Achondroplasia (22 ± 3 years) and 17 male controls (22 ± 2 years). PT mechanical properties were measured during isometric maximal voluntary contraction (iMVC) of the knee extensors using ultrasonography. The Achondroplasic group produced 54% less stress at iMVC than controls (29.4 ± 8.0 v 64.5 ± 14.0 MPa, P < 0.001, d = 3.12). Maximal excursion of the Achondroplasic PT was 22%less than controls at iMVC (7.4 ± 2.1 v 5.5 ± 1.7mm, P < 0.001, d = 0.99), but there was no difference in strain between groups (13 ± 4 v 13 ± 3%, P > 0.05). Achondroplasic PT were 47% less stiff (748 ± 93 v 1418 ± 101 N⋅mm-1, P < 0.001, d = 6.89) and had a 51% lower Young's modulus (0.39 ± 0.09 v 0.77 ± 0.14 GPa, P < 0.001, d = 3.46) than controls at iMVC. Achondroplasic PT are indeed more compliant than controls which may contribute to lower relative force production. The causes of higher Achondroplasic PT compliance are unclear but are likely due to the collagen related genetic mutation which causes Achondroplasia. [ABSTRACT FROM AUTHOR]

Zusammenfassung Die erfolgreiche Therapie von Sehnenverletzungen stellt eine große Herausforderung in der Sportorthopädie dar. Als Behandlungsziel gilt es, eine langfristig erfolgreiche Therapie und eine zeitnahe Reintegration des Athleten in den Trainings- und Wettkampfbetrieb zu gewährleisten. In der Literatur finden sich nur wenige Arbeiten, die die unterschiedlichen Therapieverfahren hinsichtlich ihrer therapeutischen Effektivität beurteilen und hieraus praxisrelevante Behandlungsempfehlungen erarbeiten. Im Fokus des GOTS Expertenmeetings 2016 stand das Themengebiet der Muskel- und Sehnenverletzungen. Das Expertenkomitee umfasste 22 Mitglieder, von denen neun der Arbeitsgruppe „Konservative Therapie von Sehnenverletzungen“ angehörten. Die erarbeiteten Behandlungsempfehlungen wurden dem gesamten Expertenrat vorgestellt und nach Begutachtung überarbeitet. Das Expertenkomitee erlangte Konsens über die konservative Therapie von Sehnenverletzungen. Die Adressierung von potentiell auslösenden Risikofaktoren und eine Lastoptimierung der Sehne, die u.a. eine gezielte Trainingstrainingstherapie beinhaltet, stellen relevante Therapiebausteine dar. Ein breites Spektrum weiterer Therapieverfahren steht potentiell zur Verfügung, deren Anwendung in Abhängigkeit der Lokalisation, des Schweregrades und zeitlichen Verlaufs der vorliegenden Verletzung individuell geprüft werden sollte. Die vorliegende Arbeit liefert eine strukturierten Überblick über die Anwendung der potentiell zur Verfügung stehenden Therapieverfahren anhand der vorliegenden evidenzbasierten Datenlage, den empirisch erfolgreich angewandten Verfahren in der Praxis und den Erkenntnissen der Grundlagenforschung. The treatment of tendon injuries in general presents one of the most relevant challenges in sports medicine, and there is high demand to ensure a long-term successful treatment and short time loss of the sport. However, there are only a few contributions providing guidance and recommendations for the nonoperative treatment of tendon injuries. The 2016 GOTS Expert Meeting, initiated by the German-Austrian-Swiss Society for Orthopaedic Traumatologic Sports Medicine (GOTS), focused on the topic of muscle and tendon injuries. The committee was composed of twenty-two medical specialists. Nine of them were delegated to a subcommittee focusing on the nonoperative treatment of tendon injuries. The recommendations and statements that were developed were reviewed by the entire consensus committee and voted on by the members. The committee reached a consensus on the utility and efficacy of the management of tendon injuries. Addressing precipitating risk factors and the concept of load management including well designed training programs are one of the most relevant steps in the treatment of tendinopathies. A wide variety of additional therapeutic approaches can be considered individually based on the underlying localisation, the grade of injury and the healing phase. The present work provides a structured overview on the diverse conservative treatment strategies of tendon injuries and evaluates their efficacy with respect to the existing scientific evidence and clinical expertise in the context of basic science on the healing process of tendon injuries. [ABSTRACT FROM AUTHOR]

To examine and compare the loading related changes in micro-morphology of the patellar tendon. Fifteen healthy young males (age 19 ± 3 yrs, body mass 83 ± 5 kg) were utilised in a within subjects matched pairs design. B mode ultrasound images were taken in the sagittal plane of the patellar tendon at rest with the knee at 90° flexion. Repeat images were taken whilst the subjects were carrying out maximal voluntary isometric contractions. Spatial frequency parameters related to the tendon morphology were determined within regions of interest (ROI) from the B mode images at rest and during isometric contractions. A number of spatial parameters were observed to be significantly different between resting and contracted images (Peak spatial frequency radius (PSFR), axis ratio, spatial Q-factor, PSFR amplitude ratio, and the sum). These spatial frequency parameters were indicative of acute alterations in the tendon micro-morphology with loading. Acute loading modifies the micro-morphology of the tendon, as observed via spatial frequency analysis. Further research is warranted to explore its utility with regard to different loading induced micro-morphological alterations, as these could give valuable insight not only to aid strengthening of this tissue but also optimization of recovery from injury and treatment of conditions such as tendinopathies. [ABSTRACT FROM AUTHOR]

The extensor mechanism of the knee can be damaged due to various modes of injury, which, in most cases, will require urgent surgical intervention for repair. Single patellar tendon ruptures are uncommon, but simultaneous bilateral events are even rarer and have been scarcely reviewed in English literature. Research in this area is mainly confined to case series, with some literature reviews but no evidence of more substantial analysis. Therefore, this systematic review was done to analyse the existing literature on bilateral simultaneous patellar tendon ruptures and propose a systematic and standardised approach to diagnosing and managing these injuries. A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search terms included 'bilateral patellar tendon rupture', 'bilateral', 'patellar', 'tendon' and 'rupture'. Three independent reviewers conducted searches in PubMed, OvidSP for Medline, Embase and the Cochrane Library using the same search strategy. The eligibility criteria included studies on bilateral concomitant patellar tendon rupture published in English. Bilateral simultaneous patellar tendon ruptures of traumatic and atraumatic origin in human patients were included. The study types comprised case reports and literature reviews. The key limitation of this study was the low number of patients covered by the eligible literature. Patellar tendon ruptures are a rare and scarcely documented injury, and there is a need for studies with a high level of evidence, especially regarding surgical treatment choice and methods, as well as post-operative management, which could potentially lead to improved outcomes in the management of this injury., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Fernandes et al.)

Zusammenfassung Das Patellaspitzensyndrom ein häufiges Überlastungssyndrom. Da es sich um keine Entzündung handelt, finden sich histologisch auch keine Entzündungszellen. Ursächlich sind oft rasche Intensitätssteigerungen, diese führen bei durch muskuläre Dysbalancen/Verkürzungen oder Achsfehlstellungen prädisponierten Sportlern zu Beschwerden. In der Standard-Diagnostik sollten Ultraschall, Farbduplex und Röntgen durchgeführt werden. Therapiert wird zunächst meist konservativ mit exzentrischem Training, Physiotherapie und ggf. Stoßwellen oder Infiltrationen. Eine schmerzadaptierte Sportpause lässt sich oft nicht vermeiden, wohingegen operative Maßnahmen meist erst nach frustraner konservativer Therapie durchgeführt werden. Präventiv sollte der Focus vor allem auf eine ausgewogene Muskelbalance und Dehnfähigkeit sowie eine gute Beinachsenstabilität gelegt werden. Der Artikel gibt einen Überblick über Epidemiologie, Risikofaktoren, Diagnostik, Therapie und Prävention. Summary Jumper's Knee is a common overuse syndrome. There is no inflammation, and histologically, there are no inflammatory cells found. Especially, quick increase of training load may lead to problems in, because of muscular dysbalances/ shortenings or axial malalignment, predisposed athletes. Standard diagnostic should contain ultrasound, colour duplex and X-rays. Initial therapy is mostly conservative with eccentric training, physiotherapy and, if necessary, extracorporal shockwaves or infiltrations. A pain-adapted sport break is often unavoidable, whereas surgery is often only performed after failed conservative treatment. With prevention, focus should be on a good balanced musculature, stretchability and stability. This article gives an overview on epidemiology, risk factors, diagnostic, therapy and prevention. [ABSTRACT FROM AUTHOR]

Avulsion fractures of the inferior pole of the patella and proximal tibial apophysis are independently rare injuries. They occur in children due to the relative weakness of the apophyseal cartilage compared to the ligaments and tendons. The combination of these two fractures, is exceedingly rare, with only a few previously described cases in the literature. Due to the infrequent presentation of this injury, careful examination and consideration of advanced imaging is important for diagnosis and preoperative planning. Here we present two cases of combined sleeve fractures of the inferior pole of the patella and tibial apophysis, with discussion of the pathophysiology, classification, identification and management of the injury.