Patellar Tendon Reconstruction Using Tibialis Posterior Allograft for Treatment of Patellar Tendon Rupture After Bone-Patellar Tendon-Bone Anterior Cruciate Ligament Reconstruction.

Background: Bone-patellar tendon-bone (BPTB) autografts are often used to treat anterior cruciate ligament (ACL) tears in young, highly active patients. These grafts are robust and provide adequate stability, allowing for return to sport and optimal functional outcomes in athletes. Patellar tendon rupture following BPTB ACL reconstruction is rare and can be difficult to treat. Case Report: A 19-year-old collegiate wrestler injured his left knee during a match. On evaluation 7 days after the injury, he was found to have increased anterior translation of the tibia on Lachman testing and an abnormal pivot shift. Magnetic resonance imaging demonstrated a complete tear of the ACL, and he successfully underwent a BPTB ACL reconstruction without complication. He progressed appropriately in the acute postoperative period. Six weeks after his index surgery, the patient reinjured his left knee and was diagnosed with a patellar tendon rupture. The previously reconstructed ACL was intact. A posterior tibialis tendon graft was used to repair the patellar tendon via a transosseous tunnel in the tibial tuberosity. The patient's recovery was complicated by a superficial wound that resolved with treatment. He achieved full range of motion and was able to return to sport. Conclusion: No technique for treating patellar tendon rupture following BPTB ACL reconstruction has been widely accepted. The treatment of this injury is left to the preference of the surgeon. This case demonstrates that tibialis posterior allografts are a viable option for the treatment of such injuries.

Surgical approach on combined chronic patellar tendon and bicruciate knee ligament injury.

A combined injury of the patellar tendon and both the anterior and posterior cruciate ligaments is disabling. It directly affects knee kinematics and biomechanics, presenting a considerable surgical challenge. In this complex and uncommon injury, decision-making should take into account the surgeon's experience and consider one- or two-stage surgery, tendon graft, graft fixation, and rehabilitation protocol. This manuscript discusses the surgical approach based on a comprehensive understanding of the patellar tendon and bicruciate biomechanics to guide which structures should be reconstructed first, especially when a two-stage procedure is chosen.

Medial patellar ligament reconstruction in combination with derotational distal femoral osteotomy for treating recurrent patellar dislocation in the presence of increased femoral anteversion: a systematic review.

BACKGROUND: Medial patellar ligament reconstruction (MPFL-R) in combination with derotational distal femoral osteotomy (DDFO) for treating recurrent patellar dislocation (RPD) in the presence of increased femoral anteversion is one of the most commonly used surgical techniques in the current clinical practice. However, there are limited studies on the clinical outcomes of MPFL-R in combination with DDFO to treat RPD in the presence of increased femoral anteversion. PURPOSE: To study the role of MPFL-R in combination with DDFO in the treatment of RPD in the presence of increased femoral anteversion. METHODS: A systematic review was performed according to the PRISMA guidelines by searching the Medline, Embase, Web of Science, and Cochrane Library databases through June 1, 2023. Studies of patients who received MPFL-R in combination with DDFO after presenting with RPD and increased femoral anteversion were included. Methodological quality was assessed using the MINORS (Methodological Index for Nonrandomized Studies) score. Each study's basic characteristics, including characteristic information, radiological parameters, surgical techniques, patient-reported outcomes, and complications, were recorded and analyzed. RESULTS: A total of 6 studies with 231 patients (236 knees) were included. Sample sizes ranged from 12 to 162 patients, and the majority of the patients were female (range, 67-100%). The mean age and follow-up ranges were 18 to 24 years and 16 to 49 months, respectively. The mean femoral anteversion decreased significantly from 34° preoperatively to 12° postoperatively. In studies reporting preoperative and postoperative outcomes, significant improvements were found in the Lysholm score, Kujala score, International Knee Documentation Committee score, and visual analog scale for pain. Postoperative complications were reported in all studies, with an overall reported complication rate of 4.7%, but no redislocations occurred during the follow-up period. CONCLUSION: For RPD with increased femoral anteversion, MPFL-R in combination with DDFO leads to a good clinical outcome and a low redislocation rate. However, there was no consensus among researchers on the indications for MPFL-R combined with DDFO in the treatment of RPD.

Ultrasound and Elastosonographic Features of the Patellar Ligament in Dogs Affected by Cranial Cruciate Ligament Disease.

This study aims to evaluate the morpho-functional change in the patellar ligament in dogs with cranial cruciate ligament disease. We hypothesized that it may show increased thickening and stiffness with increasing days from onset to diagnosis instead of trauma. Understanding this aspect has implications for the choice of timing for treating patients suffering from cranial cruciate ligament disease, as well as the contextualization of patellar ligament desmitis pictures after surgical treatment with tibial plateau leveling osteotomy or tibial tuberosity advancement. Thirty-three dogs affected by unilateral cranial cruciate disease were examined and divided into three groups based on the time elapsed from the onset of lameness to diagnosis: Group 1 (1-15 days), Group 2 (16-60 days), and Group 3 (over 60 days). Conventional B-mode ultrasonographic and elastosonographic examinations of the patellar ligament were performed without sedation for each dog. Upon ultrasonographic examination, all dogs showed modification in the echostructure of the patellar ligament. In addition, the patellar ligament tended to become harder with increasing days after disease, although there were no significant differences between groups. Our results show that as the time increases between the onset of cranial cruciate ligament disease and diagnosis and treatment, the patellar ligament progressively thickens and loses its elasticity.

A Novel Tendon Injury Model, Induced by Collagenase Administration Combined with a Thermo-Responsive Hydrogel in Rats, Reproduces the Pathogenesis of Human Degenerative Tendinopathy.

Patellar tendinopathy is a common clinical problem, but its underlying pathophysiology remains poorly understood, primarily due to the absence of a representative experimental model. The most widely used method to generate such a model is collagenase injection, although this method possesses limitations. We developed an optimized rat model of patellar tendinopathy via the ultrasound-guided injection of collagenase mixed with a thermo-responsive Pluronic hydrogel into the patellar tendon of sixty male Wistar rats. All analyses were carried out at 3, 7, 14, 30, and 60 days post-injury. We confirmed that our rat model reproduced the pathophysiology observed in human patients through analyses of ultrasonography, histology, immunofluorescence, and biomechanical parameters. Tendons that were injured by the injection of the collagenase-Pluronic mixture exhibited a significant increase in the cross-sectional area (p < 0.01), a high degree of tissue disorganization and hypercellularity, significantly strong neovascularization (p < 0.01), important changes in the levels of types I and III collagen expression, and the organization and presence of intra-tendinous calcifications. Decreases in the maximum rupture force and stiffness were also observed. These results demonstrate that our model replicates the key features observed in human patellar tendinopathy. Collagenase is evenly distributed, as the Pluronic hydrogel prevents its leakage and thus, damage to surrounding tissues. Therefore, this model is valuable for testing new treatments for patellar tendinopathy.

Rare retro-patellar multiple osteochondromas in patellar tendon: A case report.

Osteochondromas (OCs) are developmental anomalies that originate from the periosteum and typically form during enchondral ossification near the joints. Retro-patellar OC caused by exostosis forms in various intracapsular, intra-tendon, and joint-adjacent positions within the knee joint. In this case, a 19-year-old male presented with swelling and a mass in his left knee, which raised suspicion of bone tumors. After evaluating x-ray images and conducting histopathological examinations, the diagnosis was confirmed as retro-patellar OC.

SIMULTANEOUS RUPTURE OF THE PATELLAR AND CONTRALATERAL QUADRICEPS TENDONS IN A NEPHROPATHY PATIENT.

Simultaneous rupture of the patellar and contralateral quadriceps tendons in patients with chronic renal failure is an extremely rare condition, with few cases described in the medical literature. Several systemic pathological conditions that lead to a decline in kidney function can predispose individuals to spontaneous tendon rupture, such as rheumatological and endocrine diseases, and even gestational conditions, such as eclampsia. Objective: In this case report, we describe the case of a 39-year-old woman with chronic renal failure on dialysis due to a previous history of eclampsia that caused the simultaneous rupture of the patellar and contralateral quadriceps tendons. Methods: Data were collected by interviews, direct observation, and medical examinations, and include information about the case history, the patient's characteristics, the former interventions, and the results obtained. Results: The surgery to repair the patellar and contralateral quadriceps tendons was performed by transosseous tunnels and the Krackow technique with nonabsorbable sutures was used. The semitendinosus tendon was removed and used as reinforcement. Conclusion: Patient under follow-up with good functional results in both knees.Level of Evidence V, Expert Opinion.

A ruptura simultânea de tendão patelar e tendão quadricipital contralateral em paciente com insuficiência renal crônica é uma condição extremamente rara, havendo poucos casos descritos na literatura médica. Diversas condições patológicas sistêmicas que levam ao declínio das funções renais podem predispor à ruptura tendinosa espontânea, como doenças reumatológicas e endócrinas, até mesmo condições gestacionais, como a eclâmpsia. Objetivo: Neste relato de caso, descrevemos o caso de uma mulher de 39 anos com insuficiência renal crônica dialítica decorrente de quadro pregresso de eclâmpsia que culminou na ruptura simultânea de tendão patelar e tendão quadricipital contralateral. Métodos: Estudo realizado com dados coletados por meio de entrevista, observação direta e exames médicos. Os dados incluem informações sobre o histórico do caso, as características do paciente, as intervenções realizadas e os resultados obtidos. Resultados: A cirurgia para reparo da lesão de tendão patelar contralateral e tendão quadricipital foi realizada por túneis transosseos e a rafia foi feita com pontos Krakow utilizando fios não absorvíveis. Além disso, o tendão semitendinoso foi retirado e usado como reforço. Conclusão: A paciente apresentou bons resultados funcionais em ambos os joelhos operados. Nível de Evidência V, Opinião do Especialista.

Morphometry of the patellar tendon using a simple tracing method: a gold standard for anterior cruciate ligament reconstruction.

The anterior cruciate ligament (ACL) is mostly damaged in sporting activities. To reconstruct the damaged ACL, a patellar tendon (PT) is often the most preferred graft due to its fast healing and bone integration i.e. bone-patellar tendon-bone graft. Suitability of the PT often depends on the morphometric profile of the tendon. This study reported on the harvestable surface area (SA) of the tendon using a simple tracing method. The PT of 79 adult formalin-fixed cadavers of South Africans of European Ancestry were dissected, and the margins of the PT were traced on a wax paper before the tracings were scanned. The SA, straight proximal width (SPW), curved proximal width (CPW), straight distal width (SDW), curved distal width (CDW) and length of tendon (LOT) from the digitized image of the PT was measured. In addition, the length of the lower limbs was measured to normalize the measurements. The results showed no significant side differences, and the measurements were not sexually dimorphic. A strong correlation was reported for SA vs. LOT, SPW vs. CPW and SDW vs. CDW for both sexes and sides. The presented morphological profile provides additional information on the usability of the graft and with respect to healing and recovery.

Ultrasonographic comparison of the intermediate patellar ligament in warmbloods versus quarter horses.

Striations are present on ultrasonography of the intermediate (middle) patellar ligament in the transverse plane, which can be confused with tears. Comparison to the contralateral limb is often performed to help differentiate anatomic variation from pathologic change. The purposes of this prospective, observational study were to describe the striation patterns in Warmbloods and Quarter Horses, determine if these patterns are bilaterally symmetrical, and compare striation characteristics between Warmbloods and Quarter Horses. The intermediate patellar ligaments of six Warmblood horses and six Quarter horses, free from clinical signs of hindlimb lameness and in full work, were examined ultrasonographically. Striation pattern, striation number, and the transverse-sectional areas for intermediate patellar ligaments were compared between Warmbloods and Quarter horses. Striation patterns were also compared for the left and right limbs of each horse. A significant difference between breeds was identified at the mid-portion of the intermediate patellar ligament when both left and right ligaments were included (P = 0.02) and when comparing the right intermediate patellar ligament (P = 0.02). There were no other significant breed differences, and a parallel pattern was the most common pattern type. Two-thirds of the horses in this study had bilaterally symmetrical patterns within the distal aspect of their intermediate patellar ligaments, while one-third of the population were asymmetric. These results show that comparison of the contralateral limb during ultrasonography to determine if changes within the distal aspect of the intermediate patellar ligament are normal striations versus tears may lead to misdiagnosis in one-third of horses, regardless of breed. Other signs of pathology on ultrasonography should be used instead.

Analysis of factors affecting the change in relative patellar height after robotic-assisted primary total knee arthroplasty / 中华骨科杂志

Objective:To analyze the factors affecting the relative height change of the patella after primary robotic-assisted total knee arthroplasty (R-TKA).Methods:The data of 97 patients with osteoarthritis of the knee treated with R-TKA admitted from June 2021 to March 2022 were retrospectively analyzed, including 15 males and 82 females, aged 70.0±5.4 years (range, 58-80 years). The bone resection parameters of the robotic system were recorded intraoperatively, including the bone resection amount of the medial and lateral distal femur, medial and lateral posterior femoral condyle and medial and lateral tibial plateau. The Blackburne-Peel index (BPI) and Caton-Deschamps index (CDI) were used to measure the preoperative and postoperative relative patellar height on lateral radiographs, as well as the posterior tibial slope (PTS) and the change in patellar ligament length before and after surgery. The relationship between the change in relative patellar height and the variables of interest was analyzed using partial correlation and multiple linear regression.Results:The mean postoperative CDI was lower than preoperatively (0.79±0.15 vs. 0.91±0.13, t=9.69, P<0.001), and the percentage of patients with postoperative CDI<0.6 was higher than preoperatively (9.3% vs. 0; χ 2=12.92, P<0.001); the differences in mean postoperative BPI and percentage of patients with postoperative BPI<0.45 were not statistically significant compared to preoperatively (0.69±0.13 vs. 0.71±0.17, t=1.35, P=0.182; 11.3% vs. 17.5%, χ 2=1.50, P=0.220). The mean patellar ligament length on the first postoperative day was 2.29 mm shorter than preoperatively, there was a statistically significant difference ( t=5.90, P<0.001). Partial correlation analysis showed that the amount of patellar ligament length change was positively correlated with the amount of BPI and CDI change ( r=0.84, P<0.001; r=0.70, P<0.001), and the amount of PTS change and the mean distal femoral bone resection were negatively correlated with the amount of BPI ( r= -0.41, P<0.001; r=-0.32, P=0.002) and CDI ( r=-0.23, P=0.029; r=-0.25, P=0.017) change. In contrast, the amount of posterior femoral condyle bone resection and tibial plateau bone resection did not correlate with the change of BPI and CDI. Multiple linear regression analysis showed that the amount of patellar ligament length change, PTS change and the distal femoral bone resection were factors influencing the change of BPI ( β=0.03, P<0.001; β=-0.01, P<0.001; β=-0.02, P=0.021) and CDI ( β=0.02, P<0.001; β=-0.01, P=0.001; β=-0.02, P=0.008). Conclusion:Amount of patellar ligament length change, PTS change and the distal femoral bone resection are factors affecting the BPI. In order to obtain a better relative patellar height in the primary R-TKA, attention should be paid to the adjustment of the distal femoral bone resection and PTS, while taking the necessary measures to reduce the postoperative patellar ligament length changes.

Simultaneous rupture of the patellar and contralateral quadriceps tendons in a nephropathy patient / Ruptura simultânea de tendão patelar e quadricipital contralateral em paciente nefropata

ABSTRACT Simultaneous rupture of the patellar and contralateral quadriceps tendons in patients with chronic renal failure is an extremely rare condition, with few cases described in the medical literature. Several systemic pathological conditions that lead to a decline in kidney function can predispose individuals to spontaneous tendon rupture, such as rheumatological and endocrine diseases, and even gestational conditions, such as eclampsia. Objective: In this case report, we describe the case of a 39-year-old woman with chronic renal failure on dialysis due to a previous history of eclampsia that caused the simultaneous rupture of the patellar and contralateral quadriceps tendons. Methods: Data were collected by interviews, direct observation, and medical examinations, and include information about the case history, the patient's characteristics, the former interventions, and the results obtained. Results: The surgery to repair the patellar and contralateral quadriceps tendons was performed by transosseous tunnels and the Krackow technique with nonabsorbable sutures was used. The semitendinosus tendon was removed and used as reinforcement. Conclusion: Patient under follow-up with good functional results in both knees. Level of Evidence V, Expert Opinion.

RESUMO A ruptura simultânea de tendão patelar e tendão quadricipital contralateral em paciente com insuficiência renal crônica é uma condição extremamente rara, havendo poucos casos descritos na literatura médica. Diversas condições patológicas sistêmicas que levam ao declínio das funções renais podem predispor à ruptura tendinosa espontânea, como doenças reumatológicas e endócrinas, até mesmo condições gestacionais, como a eclâmpsia. Objetivo: Neste relato de caso, descrevemos o caso de uma mulher de 39 anos com insuficiência renal crônica dialítica decorrente de quadro pregresso de eclâmpsia que culminou na ruptura simultânea de tendão patelar e tendão quadricipital contralateral. Métodos: Estudo realizado com dados coletados por meio de entrevista, observação direta e exames médicos. Os dados incluem informações sobre o histórico do caso, as características do paciente, as intervenções realizadas e os resultados obtidos. Resultados: A cirurgia para reparo da lesão de tendão patelar contralateral e tendão quadricipital foi realizada por túneis transosseos e a rafia foi feita com pontos Krakow utilizando fios não absorvíveis. Além disso, o tendão semitendinoso foi retirado e usado como reforço. Conclusão: A paciente apresentou bons resultados funcionais em ambos os joelhos operados. Nível de Evidência V, Opinião do Especialista.

Treatment of Jumper's Knee with Extracorporeal Shockwave Therapy: A Systematic Review and Meta-Analysis.

The aim of this systematic review and meta-analysis was to determine the therapeutic efficacy of extracorporeal shockwave therapy (ESWT) for athletes with patellar tendinopathy. We searched PubMed, EBSCOHost and Ovid for randomized controlled trials (RCTs) which evaluated the therapeutic efficacy of ESWT in athletes with jumper's knee. The methodological quality of RCTs was rated with the Physiotherapy Evidence Database scale. Data in the meta-analysis were expressed as standardized mean difference (SMDs) and 95% confidence intervals (CIs). Heterogeneity was assessed with I2 statistics. Of 192 records identified, a total of seven articles met the inclusion criteria. The ESWT and control groups with any other conservative treatment did not differ significantly with respect to the Visual Analogue Scale (VAS) long-term scores obtained at ≥ 6 months of therapy completion (SMD: -0.33; 95% CI: -4.64 to 3.98; p = 0.87; I2= 98%). Furthermore, no significant differences were found between the ESWT and control groups regarding the pooled Victorian Institute of Sports Assessment for Patella (VISA-P) scores for long-term outcomes (SMD: 8.21; 95% CI: -39.3 to 55.73; p = 0.73; I2= 99%). The ESWT and control groups did not differ significantly on the VAS and VISA-P scores for long-term outcomes. In both cases, heterogeneity was considered to be high. Hence, no clear and generalized conclusions can be drawn regarding ESWT effectiveness in athletes with patellar tendinopathy.

Allogeneic Tendon Transplantation for the Treatment of Pathological Patellar Ligament Defect in Children: Technical Note and 4-Year Follow-Up.

OBJECTIVE: The absence of patellar ligament will bring about a severe negative impact on daily life. Many reconstruction techniques have been described in adults. However, there is a lack of technical introduction regarding the reconstruction of the patellar ligament in children. The purpose of this study was to report a surgical technique for reconstructing the patellar ligament in children. METHOD: A retrospective analysis of the clinical data on a patellar ligament (tendon sheath fibroma) patient with allogeneic tendon reconstruction. An 8-year-old child with postoperative recurrence of left patellar ligament tumor was enrolled in our study. Anterior tibialis tendon allograft was used to reconstruct the patellar ligament after complete resection of the patellar ligament for the tumor. The tunnels were constructed on the deep surface of the tibial tubercle and the root of the quadriceps tendon (to decrease the harmful impact on patella development), respectively. The allogeneic tendon was passed through the tunnels above in the shape of "8," and the two ends of the tendon were attached to the bleeding bone bed at the inferior edge of the patella with suture anchors to achieve better bone-tendon healing. During the follow-up, the knee's range of motion and imaging manifestations were recorded. RESULT: Postoperative pathology suggests chondromesenchymal hamartoma, a rare benign soft tissue tumor different from the previous operation (tendon sheath fibroma). During the 4-year follow-up, the patient's active range of motion of the knee achieved 0° to 120°; and the patient could walk normally without any external help. Physical examinations (the apprehension sign and J sign) showed no ligamentous instability or patellar ligament tenderness. Imaging analysis showed that the ratio length of the patellar ligament to the patella was almost normal. The integrity, continuity, and shape of the allogeneic ligament showed excellent results in MRI. Combined with clinical and imaging findings, allogeneic tendon patellar ligament reconstruction was deemed successful. CONCLUSION: Allogeneic ligament reconstruction technique can provide a treatment option by reconstructing the extensor mechanism, minimizing the impact on patellar development, and augmenting biological healing for children with the absence of the patellar ligament.

A Mouse Model of Cancer Induced Bone Pain: From Pain to Movement.

Cancer induced bone pain (CIBP) occurs in patients with advanced osteosarcoma or metastasized bone tumors that can negatively affects the patient's quality of life. However, motor impairment in CIBP is still understudied. To improve the quality of life of patients with CIBP, the study of CIBP induced movement impairment is of particular importance. Here, we presented a model of metastatic cancer induced bone pain caused by an allograft of Lewis lung cancer cells. In this method, we injected Lewis lung cancer cells into the femoral medulla cavity and recorded the pain behavior and motor behavior after CIBP surgery. We observed enhanced pain after the initial surgery. Interestingly, we found the latency on rotarod was significantly reduced concomitant with tumor growth and pain. This result indicated that the motor coordination and balance were severely impaired in CIBP. We also found the pain and motor behavioral differences in models that severed the patellar ligament vs. maintaining the patellar ligament. These findings provide a novel clue for further investigating the mechanisms responsible for the generation and development of CIBP.

A comparative study of treatment interventions for patellar tendinopathy: a secondary cost-effectiveness analysis.

OBJECTIVE: To compare the cost-effectiveness of three patellar tendinopathy treatments. DESIGN: Secondary (cost-effectiveness) analysis of a blinded, randomised controlled trial, with follow-up at 10 and 22 weeks. SETTINGS: Recruitment was performed in sport clubs. The diagnosis and the intervention were carried out at San Jorge University. PARTICIPANTS: The participants were adults between 18 and 45 years (n = 48) with patellar tendinopathy. INTERVENTIONS: Participants received percutaneous needle electrolysis, dry needling or sham needling, all of which were combined with eccentric exercise. MAIN OUTCOME MEASURES: Costs, quality-adjusted life years and incremental cost-effectiveness ratio were calculated for each group. RESULTS: The total cost per session was similar in the three groups: €9.46 for the percutaneous needle electrolysis group; €9.44 for the dry needling group; and €8.96 for the sham group. The percutaneous needle electrolysis group presented better cost-effectiveness in terms of quality-adjusted life years and 96% and 93% probability of being cost-effective compared to the sham and dry needling groups, respectively. CONCLUSION: Our study shows that percutaneous needle electrolysis has a greater probability of being cost-effective than sham or dry needling treatment.

Exploring Anatomo-Morphometric Characteristics of Infrapatellar, Suprapatellar Fat Pad, and Knee Ligaments in Osteoarthritis Compared to Post-Traumatic Lesions.

Several studies have investigated cartilage degeneration and inflammatory subchondral bone and synovial membrane changes using magnetic resonance (MR) in osteoarthritis (OA) patients. Conversely, there is a paucity of data exploring the role of knee ligaments, infrapatellar fat pad (IFP), and suprapatellar fat pad (SFP) in knee OA compared to post-traumatic cohorts of patients. Therefore, the aim of this study was to analyze the volumetric and morphometric characteristics of the following joint tissues: IFP (volume, surface, depth, femoral and tibial arch lengths), SFP (volume, surface, oblique, antero−posterior, and cranio−caudal lengths), anterior (ACL) and posterior cruciate ligament (PCL) (volume, surface, and length), and patellar ligament (PL) (volume, surface, arc, depth, and length). Eighty-nine MR images were collected in the following three groups: (a) 32 patients with meniscal tears, (b) 29 patients with ACL rupture (ACLR), and (c) 28 patients affected by end-stage OA. Volume, surface, and length of both ACL and PCL were determined in groups a and c. A statistical decrease of IFP volume, surface, depth, femoral and tibial arch lengths was found in end-stage OA compared to patients with meniscal tear (p = 0.002, p = 0.008, p < 0.0001, p = 0.028 and p < 0.001, respectively) and patients with ACLR (p < 0.0001, p < 0.0001, p = 0.008 and p = 0.011, respectively). An increment of volume and surface SFP was observed in group b compared to both groups a and c, while no differences were found in oblique, antero−posterior, and cranio−caudal lengths of SFP among the groups. No statistical differences were highlighted comparing volume, surface, arc, and length of PL between the groups, while PL depth was observed to be decreased in end-OA patients compared with meniscal tear patients (p = 0.023). No statistical differences were observed comparing ACL and PCL lengths between patients undergoing meniscectomy and TKR. Our study confirms that IFP MR morphometric characteristics are different between controls and OA, supporting an important role of IFP in OA pathology and progression in accordance with previously published studies. In addition, PL depth changes seem to be associated with OA pathology. Multivariate analysis confirmed that OA patients had a smaller IFP compared to patients with meniscal tears, confirming its involvement in OA.

[Measurement of external deviation angle of patellar tendon and its application on diagnosis of recurrent patellar dislocation].

OBJECTIVE: To compare computed tomography (CT) measurement results of external deviation angle of patellar tendon and tibia tubercle-trochlea groove (TT-TG), as well as the diagnostic ability and pathology in recurrent patellar dislocation threshold. METHODS: From January 2015 to March 2020, 46 patients with recurrent patella dislocation and 112 patients with non-patella dislocation were retrospectively analyzed. Forty-six patients with recurrent patella dislocation were divived into 2 groups according to TT-TG value, 11 patients with patellar dislocation with TT-TG≥20 mm(group A), including 7 males and 4 females, aged from 16 to 27 years old with an average of(21.00±3.98) years old; 35 patients with patellar dislocation with TT-TG<20 mm(group B), including 14 males and 21 females, aged from 16 to 37 years old with an average of(22.83±6.09) years old. While 112 patients with non-patella dislocation(group C) included 63 males and 49 females, aged 16 to 36 years old with an average of(22.87±5.69) years old. The measurement data of external deviation angle of patellar tendon and TT-TG value among three groups were compared. Spearman analysis was used to analyze correlation among them. Intraclass correlation coefficient (ICC) was used to determine repeatability within group. Receiver operating characteristic (ROC) area under the curve was used to evaluate diagnostic ability of parameters, and calculate osteotomy parameters of external deviation angle of patellar tendon, as well as external deviation angle of patellar tendon and TT-TG value in the diagnosis of recurrent patella diagnostic parameters of dislocation. RESULTS: External deviation angle of patellar tendon in group A, B and C was (22.04±3.09)°, (17.20±4.43)°and (10.22±3.45)° respectively;while TT-TG value was(21.15±0.71) mm, (15.97±2.69) mm and (11.12±3.77) mm, there were significance among three groups (P<0.01), and had difference between group A and B(P<0.01). There was strong positive correlation between external deviation angle of patellar tendon and TT-TG value (r=0.735, P<0.000 1). The intra-group ICC value(0.980, 0.982) of external deviation angle of patellar tendon in group A and B have better repeatability than TT-TG value (0.594, 0.775). The external deviation angle of patellar tendon in group C(0.956) and repeatability of TT-TG value(0.906) was very good. In the diagnosis of recurrent patellar dislocation, the area under ROC curve of external deviation angle of patellar tendon (0.916) was greater than TT-TG value(0.886), and diagnostic parameters were 13.84°and 14.69 mm, respectively;in tibial osteotomy, the area under ROC curve of external deviation angle of patellar tendon was 0.821, and osteotomy parameter was 20.15°. CONCLUSION: CT imaging could reliably measure external deviation angle of patellar tendon.There is a strong positive correlation between external deviation angle of patellar tendon and value of TT-TG, which could be used to determine pathological state of recurrent patellar dislocation, and external deviation angle of patellar tendon is superior to the TT-TG value in the diagnosis of recurrent patellar dislocation. The external deviation angle of patellar tendon could also be used to guide the formulation of the tibial osteotomy plan for recurrent patellar dislocation.

Incidence of Patellar Desmopathy in the Modified Maquet Technique with and without PRGF.

Patellar desmopathy can lead to desmitis, discomfort, and lameness. In the traditional MMT, a pin is used for the fixation of the fragment of the osteotomized tibia to the implant and the tibial diaphysis; this pin needs to be placed below the insertion of the patellar ligament to avoid damaging it. Considering the differences between TTA and MMT, the authors consider it important to determine the incidence of patellar desmopathy in the MMT. This is a prospective study that enrolled 53 owned dogs that underwent MMT and were followed up by a complete examination and radiograph controls to establish the patellar tendon thickening and the presence of clinical desmitis. The PRGF were administrated to 29 of those patients, in order to determine if PRGF's action could decrease ligament desmitis. The conclusions in this study were that the desmopathy produced by the MMT is similar to that generated by the TTA if the pin is carefully placed; in addition, the PRGF did not decrease the inflammation and the thickening of the ligament.

Patellar Dislocation and Fracture After Medial Patellofemoral Ligament Reconstruction in a Patient With Osteogenesis Imperfecta.

Background: Patellar instability is a common orthopedic condition in the pediatric population. Many factors contribute to patellar instability, including trochlear dysplasia. However, patellar instability and its treatments are not well documented in the literature for patients with osteogenesis imperfecta. Case Report: After medial patellofemoral ligament (MPFL) reconstruction, a 17-year-old male with osteogenesis imperfecta had a patellar dislocation that resulted in a patellar fracture. The patient subsequently had a revision of his MPFL reconstruction, and at 2½ years postoperation has had no episodes of recurrent patellar instability. Conclusion: The combination of bone fragility, trochlear dysplasia, and strength of the allograft used for MPFL reconstruction compared to the patient's bone strength led to dislocation and patellar fracture. Research into alternative methods for patellar fixation and postoperative physical therapy protocols for patients with osteogenesis imperfecta is needed. Special considerations must be made for this patient population.

Decreasing patellar tendon stiffness during exercise therapy for patellar tendinopathy is associated with better outcome.

OBJECTIVES: To assess the associations between: 1) baseline patellar tendon stiffness and clinical outcome after exercise therapy in athletes with patellar tendinopathy and 2) the change in patellar tendon stiffness and clinical outcome during progressive tendon-loading exercise therapy and eccentric exercise therapy. DESIGN: Randomized controlled trial. METHODS: Athletes with patellar tendinopathy aged 18-35 years, playing tendon-loading sports at least 3 times per week were randomized in a 1:1 ratio between progressive tendon-loading exercise therapy and eccentric exercise therapy for 24 weeks. Patellar tendinopathy was diagnosed clinically, and confirmed by ultrasound. Patellar tendon stiffness (kilopascal, kPa) was assessed using shear-wave elastography. Clinical outcome was assessed using the validated Victorian Institute of Sports Assessment (VISA-P; range 0-100) questionnaire. Both were assessed at baseline, 12 and 24 week follow-up. Adjusted general linear, mixed-linear models and Generalized Estimating Equations were used. RESULTS: We included 76 athletes (58 men, mean age 24 ±â€¯4 years). No association was found between baseline stiffness and VISA-P after 24 weeks (p = 0.52). Decreased stiffness (adjusted mean difference = 10 kPa (95% CI: 4-15) was significantly associated with improved clinical outcome at 12 weeks in all athletes (p = 0.02), and at both 12 and 24 weeks (p = 0.01) in athletes allocated to progressive tendon-loading exercise therapy. CONCLUSIONS: Patellar tendon stiffness, assessed with shear-wave elastography, is unsuitable to use as a single predictive measurement for clinical outcome. Decreasing stiffness during the course of exercise therapy is associated with improved clinical outcome in athletes recovering from patellar tendinopathy.