The Number of Patellar Dislocation Events Is Associated With Increased Chondral Damage of the Trochlea.

BACKGROUND: Patellofemoral instability is associated with chondral injuries to the patella, trochlea, and lateral femoral condyle. Although studies have demonstrated an association between patellar dislocations and chondral injuries, the influence of the number of dislocations on chondrosis is not established. PURPOSE: To elucidate the precise association between the number of patellar dislocation events and the severity of chondral injuries in a multicenter cohort study at the time of patellar stabilization procedures. STUDY DESIGN: Cross-sectional study; Level of evidence, 2. METHODS: A prospective multicenter cohort study (JUPITER [Justifying Patellar Instability Treatment by Early Results]) database was queried for cases of primary patellofemoral instability procedures from December 2016 to September 2022. Cartilage lesions were classified using the International Cartilage Repair Society (ICRS) classification system during an arthroscopic or open evaluation (direct visualization), with grades 2 to 4 considered abnormal. The number of dislocations was categorized as 1, 2-5, and >5. Categorical variables were compared with the chi-square test, and binary logistic regression was performed to identify predictors of the presence of chondral lesions. RESULTS: A total of 938 knees (mean age, 16.2 ± 3.8 years; 61.4% female) were included, with 580 (61.8%) demonstrating a chondral injury. The most affected region was the patella (n = 498 [53.1%]), followed by the lateral femoral condyle (n = 117 [12.5%]) and trochlea (n = 109 [11.6%]). There were no differences in the presence (P = .17) or grade (P = .63) of patellar lesions by the number of dislocations. Patients with >5 dislocations more frequently had trochlear chondral lesions (19.8%) compared with those with fewer dislocations (1, 7.6%; 2-5, 11.0%; P < .001). More dislocations were also associated with a higher proportion of ICRS grade 2 to 4 trochlear lesions (>5, 15.3%; 2-5, 10.0%; 1, 6.9%; P = .015). Combined patellar and trochlear lesions were also more common in those with >5 dislocations (P = .001). In multivariable regression, >5 dislocations was the only variable predictive of a trochlear lesion (odds ratio, 3.03 [95% CI, 1.65-5.58]; P < .001). CONCLUSION: This large prospective cohort study demonstrated that recurrent patellar dislocations can lead to more severe chondral damage in specific locations in the knee. More than 5 dislocations was associated with a >3-fold increase in the incidence and severity of trochlear chondral injuries. There were no differences in the presence or grade of patellar lesions by the number of dislocations. These findings should caution surgeons regarding prolonged nonoperative treatment.

Predicting Musculoskeletal Loading at Common Running Injury Locations Using Machine Learning and Instrumented Insoles.

INTRODUCTION: Wearables have the potential to provide accurate estimates of tissue loads at common running injury locations. Here we investigate the accuracy by which commercially available instrumented insoles (ARION; ATO-GEAR, Eindhoven, The Netherlands) can predict musculoskeletal loading at common running injury locations. METHODS: Nineteen runners (10 males) ran at five different speeds, four slopes, with different step frequencies, and forward trunk lean on an instrumented treadmill while wearing instrumented insoles. The insole data were used as input to an artificial neural network that was trained to predict the Achilles tendon strain, and tibia and patellofemoral stress impulses and weighted impulses (damage proxy) as determined with musculoskeletal modeling. Accuracy was investigated using leave-one-out cross-validation and correlations. The effect of different input metrics was also assessed. RESULTS: The neural network predicted tissue loading with overall relative percentage errors of 1.95 ± 8.40%, -7.37 ± 6.41%, and -12.8 ± 9.44% for the patellofemoral joint, tibia, and Achilles tendon impulse, respectively. The accuracy significantly changed with altered running speed, slope, or step frequency. Mean (95% confidence interval) within-individual correlations between modeled and predicted impulses across conditions were generally nearly perfect, being 0.92 (0.89 to 0.94), 0.95 (0.93 to 0.96), and 0.95 (0.94 to 0.96) for the patellofemoral, tibial, and Achilles tendon stress/strain impulses, respectively. CONCLUSIONS: This study shows that commercially available instrumented insoles can predict loading at common running injury locations with variable absolute but (very) high relative accuracy. The absolute error was lower than the methods that measure only the step count or assume a constant load per speed or slope. This developed model may allow for quantification of in-field tissue loading and real-time tissue loading-based feedback to reduce injury risk.

Prediction of specific structural damage to the knee joint using qualitative isokinetic analysis.

BACKGROUND: An isokinetic moment curve (IMC) pattern-damaged structure prediction model may be of considerable value in assisting the diagnosis of knee injuries in clinical scenarios. This study aimed to explore the association between irregular IMC patterns and specific structural damages in the knee, including anterior cruciate ligament (ACL) rupture, meniscus (MS) injury, and patellofemoral joint (PFJ) lesions, and to develop an IMC pattern-damaged structure prediction model. METHODS: A total of 94 subjects were enrolled in this study and underwent isokinetic testing of the knee joint (5 consecutive flexion-extension movements within the range of motion of 90°-10°, 60°/s). Qualitative analysis of the IMCs for all subjects was completed by two blinded examiners. A multinomial logistic regression analysis was used to investigate whether a specific abnormal curve pattern was associated with specific knee structural injuries and to test the predictive effectiveness of IMC patterns for specific structural damage in the knee. RESULTS: The results of the multinomial logistic regression revealed a significant association between the irregular IMC patterns of the knee extensors and specific structural damages ("Valley" - ACL, PFJ, and ACL + MS, "Drop" - ACL, and ACL + MS, "Shaking" - ACL, MS, PFJ, and ACL + MS). The accuracy and Macro-averaged F1 score of the predicting model were 56.1% and 0.426, respectively. CONCLUSION: The associations between irregular IMC patterns and specific knee structural injuries were identified. However, the accuracy and Macro-averaged F1 score of the established predictive model indicated its relatively low predictive efficacy. For the development of a more accurate predictive model, it may be essential to incorporate angle-specific and/or speed-specific analyses of qualitative and quantitative data in isokinetic testing. Furthermore, the utilization of artificial intelligence image recognition technology may prove beneficial for analyzing large datasets in the future.

Prospective assessment of functional and clinical results of surgical patellar stabilization in rural and urban populations. Equal chance to success?

INTRODUCTION AND OBJECTIVE: Patella dislocation represents 3.3% of all knee injuries often leading to persistent instability. Medial patello-femoral ligament(MPFL) reconstruction is the standard method of treatment in the patellar instability. Rehabilitation after MPFL-R is a long and demanding procedure. The hypothesis presented reflects the idea that despite relatively good access to hospital care and surgical options, the post-operative rehabilitation care system is still inferior in rural areas versus the one offered in major cities and towns. MATERIAL AND METHODS: Between January 2015 - January 2018, 47 patients met the study inclusion criteria, diagnosed and operated on due to patellar instability. 8 patients were lost for full follow-up. Finally, 39 patients were included, divided into two groups - group A (19 from cities), group B (20 from rural area). Prospective KOOS and Kujala scales assessments were conducted: preoperative, 6 and 12 months after surgery. Knee isokinetic muscle strength was measured at 3 stages; prior to surgery, 6 and 12 months after reconstruction. RESULTS: All patients showed significant improvement measured in the KOOS and Kujala scales after the procedure, compared to the pre-operational results. Despite equal clinical improvement, patients from Group A(city) achieved better functional outcomes as presented in the results of knee extensor functional tests using a Biodex dynamometer. CONCLUSIONS: Rehabilitation after MPFL reconstruction improves muscle strength and clinical outcome. Patients from rural areas had inferior functional results in comparison to the patients from major cities, even 12 months after surgical patella stabilization. Despite the development of roads and transport according to the EU cohesion policy, there are still differences in rehabilitation results between rural and city areas.

Midterm outcomes of patellofemoral arthroplasty / Resultados a medio plazo de la artroplastia femoropatelar

Background: The purpose of this study is the evaluation of the patellofemoral arthroplasty (PFA) survival and clinical and radiological outcomes in our institution. Methods: A retrospective evaluation of our institution patellofemoral arthroplasty cases from 2006 to 2018 was performed; the n sample after applying exclusion and inclusion criteria was 21. All patients excepting one were female with a median age of 63 (20–78). A Kaplan–Meier survival analysis at ten years was calculated. Informed consent was obtained from all patients prior being included in the study. Results: The total revision rate was 6 out of 21 patients (28.57%). The progression of the osteoarthritis in the tibiofemoral compartment was the main cause (50% of revision surgeries). The degree of satisfaction with the PFA was high, with a mean Kujala score of 70.09 and a mean OKS of 35.45 points. The VAS score improved significantly (p<0.001) from a preoperative mean of 8.07 to a postoperative mean of 3.45, with an average improvement of 5 (2–8). Survival at 10 years, with revision for any reason as the endpoint, was 73.5%. A significant positive correlation between BMI and the WOMAC pain (r=0.72, p<0.01) and between BMI and the post-operative VAS (r=0.67, p<0.01) was observed. Conclusions: The results of the case series under consideration suggest that PFA could be a possibility in the joint preservation surgery on the isolated patellofemoral osteoarthritis. BMI >30 seems to be a negative predictor factor in relationship with the postoperative satisfaction, increasing the pain proportionally to this index and requiring more replacement surgery than patients with BMI <30. Meanwhile the radiologic parameters of the implant are not correlated with the clinical or functional outcomes.(AU)

Antecedentes: El propósito de este estudio es la evaluación de la supervivencia de la prótesis femoropatelar y los resultados clínicos y radiológicos en nuestro centro. Métodos: En el presente estudio se realiza una evaluación retrospectiva de los casos de prótesis femoropatelar en nuestro centro entre los años 2006 y 2018. El tamaño muestral, tras aplicar los criterios de inclusión y de exclusión, fue de 21 pacientes. Todos los pacientes excepto uno fueron mujeres, con una media de edad de 63 años (rango 20-78). Se calculó una gráfica de Kaplan-Meier de supervivencia en los primeros 10 años. El consentimiento informado de todos los pacientes fue obtenido previamente a la inclusión en este estudio. Resultados: La tasa de recambio a prótesis total fue 6 de 21 pacientes (28,57%). La progresión de la osteoartrosis en el compartimento tibiofemoral fue la causa principal (50% de las cirugías de revisión). El grado de satisfacción con la PFA fue alto, con una media en la escala de Kujala de 70,09 y una media de OKS de 35,45 puntos. La EVA mejoró significativamente (p<0,001), de una media preoperatoria de 8,07 a una media postoperatoria de 3,45, siendo la media de mejoría de 5 puntos (2 a 8 puntos). La supervivencia a los 10 años, con rescate de la prótesis debido a cualquier causa, fue del 73,5%. Se observó una correlación positiva ente el IMC y la escala WOMAC (r=0,72, p>0,01) y entre el IMC y la EVA postoperatoria (r=0,67 y p<0,01). Conclusiones: Los resultados de esta serie de casos mostraron que la prótesis femoropatelar puede ser una alternativa de tratamiento como cirugía de preservación de la osteoartritis femoropatelar aislada. El IMC>30 parece ser un factor predictor negativo en relación con la satisfacción postoperatoria, incrementando el dolor con una correlación positiva con este índice y requiriendo mayor cirugía de reemplazo que los pacientes con IMC<30. Por otra parte, los parámetros radiológicos relacionados con el implante no están...(AU)

[Artículo traducido] Resultados a medio plazo de la artroplastia femoropatelar / Midterm outcomes of patellofemoral arthroplasty

Background: The purpose of this study is the evaluation of the patellofemoral arthroplasty (PFA) survival and clinical and radiological outcomes in our institution. Methods: A retrospective evaluation of our institution patellofemoral arthroplasty cases from 2006 to 2018 was performed; the n sample after applying exclusion and inclusion criteria was 21. All patients excepting one were female with a median age of 63 (20–78). A Kaplan–Meier survival analysis at ten years was calculated. Informed consent was obtained from all patients prior being included in the study. Results: The total revision rate was 6 out of 21 patients (28.57%). The progression of the osteoarthritis in the tibiofemoral compartment was the main cause (50% of revision surgeries). The degree of satisfaction with the PFA was high, with a mean Kujala score of 70.09 and a mean OKS of 35.45 points. The VAS score improved significantly (p<0.001) from a preoperative mean of 8.07 to a postoperative mean of 3.45, with an average improvement of 5 (2–8). Survival at 10 years, with revision for any reason as the endpoint, was 73.5%. A significant positive correlation between BMI and the WOMAC pain (r=0.72, p<0.01) and between BMI and the post-operative VAS (r=0.67, p<0.01) was observed. Conclusions: The results of the case series under consideration suggest that PFA could be a possibility in the joint preservation surgery on the isolated patellofemoral osteoarthritis. BMI >30 seems to be a negative predictor factor in relationship with the postoperative satisfaction, increasing the pain proportionally to this index and requiring more replacement surgery than patients with BMI <30. Meanwhile the radiologic parameters of the implant are not correlated with the clinical or functional outcomes.(AU)

Antecedentes: El propósito de este estudio es la evaluación de la supervivencia de la prótesis femoropatelar y los resultados clínicos y radiológicos en nuestro centro. Métodos: En el presente estudio se realiza una evaluación retrospectiva de los casos de prótesis femoropatelar en nuestro centro entre los años 2006 y 2018. El tamaño muestral, tras aplicar los criterios de inclusión y de exclusión, fue de 21 pacientes. Todos los pacientes excepto uno fueron mujeres, con una media de edad de 63 años (rango 20-78). Se calculó una gráfica de Kaplan-Meier de supervivencia en los primeros 10 años. El consentimiento informado de todos los pacientes fue obtenido previamente a la inclusión en este estudio. Resultados: La tasa de recambio a prótesis total fue 6 de 21 pacientes (28,57%). La progresión de la osteoartrosis en el compartimento tibiofemoral fue la causa principal (50% de las cirugías de revisión). El grado de satisfacción con la PFA fue alto, con una media en la escala de Kujala de 70,09 y una media de OKS de 35,45 puntos. La EVA mejoró significativamente (p<0,001), de una media preoperatoria de 8,07 a una media postoperatoria de 3,45, siendo la media de mejoría de 5 puntos (2 a 8 puntos). La supervivencia a los 10 años, con rescate de la prótesis debido a cualquier causa, fue del 73,5%. Se observó una correlación positiva ente el IMC y la escala WOMAC (r=0,72, p>0,01) y entre el IMC y la EVA postoperatoria (r=0,67 y p<0,01). Conclusiones: Los resultados de esta serie de casos mostraron que la prótesis femoropatelar puede ser una alternativa de tratamiento como cirugía de preservación de la osteoartritis femoropatelar aislada. El IMC>30 parece ser un factor predictor negativo en relación con la satisfacción postoperatoria, incrementando el dolor con una correlación positiva con este índice y requiriendo mayor cirugía de reemplazo que los pacientes con IMC<30. Por otra parte, los parámetros radiológicos relacionados con el implante no están...(AU)

Surgical Stabilization for Recurrent Patellar Instability in Competitive Wrestlers: Outcomes, Reoperations, and Return to Play at 6-Year Mean Follow-up.

BACKGROUND: The extent to which recurrent patellar instability (RPI) affects wrestlers has not been thoroughly examined. PURPOSE: To assess return to wrestling (RTW), patient-reported outcomes, and reoperation rates after patellofemoral stabilization surgery (PFSS) for RPI in a cohort of competitive wrestlers. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: All competitive wrestlers with a history of RPI and subsequent PFSS performed at a single institution between 2000 and 2020 were identified. Primary PFSS procedures included medial patellofemoral (MPFL) reconstruction (n = 31; 50%); MPFL repair (n = 22; 35.5%); or other PFSS (n = 9; 14.5%), such as tibial tubercle osteotomy, lateral retinacular release, and/or medial retinacular reefing. Exclusion criteria included revision PFSS or concomitant anterior cruciate ligament reconstruction or multiligament knee injury. Surgical failure was defined as subsequent patellar dislocation despite operative management or need for secondary PFSS. RESULTS: Ultimately, 62 knees in 56 wrestlers with a mean age of 17.0 years (range, 14.0-22.8 years) were included at a mean follow-up of 6.6 years (range, 2.0-18.8 years). RTW occurred in 55.3% of wrestlers at a mean ± SD 8.8 ± 6.7 months. Among PFSS types, no differences were observed in rates of RTW (P = .676), postoperative pain (P = .176), Tegner activity level (P = .801), International Knee Documentation Committee (P = .378), Lysholm (P = .402), or Kujala scores (P = .370). RPI was the most common postoperative complication (n = 13; 21.0%). MPFL reconstruction had the lowest rate of RPI (6.5% vs 27.3% [repair] vs 55.6% [other]; P = .005) and surgical failure (9.7% vs 31.8% [repair] vs 55.6% [other]; P = .008). Kaplan-Meier survivorship free from surgical failure of the entire cohort was 91.9% at 1 year, 77.7% at 5 years, and 65.7% at 15 years. MPFL reconstruction had the highest survivorship when compared with MPFL repair and other PFSS up to 10 years after the index surgery (90.3% vs 64.1% vs 27.8%; P = .048). CONCLUSION: RPI remains a concern for competitive wrestlers after PFSS. MPFL reconstruction may serve as a more durable surgical treatment option with lower rates of RPI and failure when compared with other PFSS procedures at up to 10 years after surgery.

Patellofemoral articular cartilage damage is associated with poorer patient-reported outcomes following isolated medial patellofemoral ligament reconstruction.

PURPOSE: The purpose of this study was to investigate the impact of articular cartilage damage on outcomes following medial patellofemoral ligament (MPFL) reconstruction. METHODS: Record review identified 160 patients who underwent isolated MPFL reconstruction at a single institution between 2008 and 2016. Patient demographics, patellofemoral articular cartilage status at surgery, and patient anatomical measures from imaging were obtained via chart review. Patients were contacted and outcomes assessed through collection of Norwich Patellar Instability (NPI) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Marx activity score as well as an assessment for recurrent patellar dislocation. Outcomes of patients with grade 0-II patellofemoral cartilage damage were compared to those of patients with grade III-IV cartilage damage. RESULTS: One hundred twenty-two patients (76%) with a minimum of one year follow-up were contacted at a mean of 4.8 years post-operatively. A total of 63 patients (52%) had grade III or IV patellofemoral chondral damage at the time of surgery. The majority of the defects was on the medial patella (46 patients-72%) and the mean patellar defect size was 2.8 cm2. Among 93 patients who completed patient-reported outcome scores, the 52 with grade III or IV chondral damage reported a significantly poorer KOOS Quality of Life than the 44 patients with grade 0 to II chondral damage (p = 0.041), controlling for patient age, sex, BMI, and anatomical factors. CONCLUSION: Patients with grade III or IV articular cartilage damage of the patellofemoral joint at the time of MPFL reconstruction demonstrated poorer KOOS knee-related quality of life than patients without grade III or IV articular cartilage damage at a mean of 4.8 years following isolated MPFL reconstruction. LEVEL OF EVIDENCE: Level II.

Accelerated rehabilitation program following medial patellofemoral ligament reconstruction does not increase risk of recurrent instability.

BACKGROUND: Rehabilitation protocols following medial patellofemoral ligament (MPFL) reconstruction were historically restrictive, with patients often immobilized and/or given weightbearing restrictions. However, more recently published protocols have been more aggressive. We compared patient-reported outcomes and recurrent dislocation risk between patients treated with a restrictive rehabilitation program (early post-operative bracing and weightbearing restrictions) and an accelerated rehabilitation protocol (no post-operative bracing or weightbearing restrictions) following MPFL reconstruction. METHODS: Patients who underwent isolated MPFL reconstruction at an academic center between 2008 and 2016 were identified. Patient demographics, anatomical measurements, surgical details, and outcomes were collected. During this period, the rehabilitation protocol at the center transitioned from a restrictive to an accelerated rehabilitation protocol. Failure risk and patient-reported outcomes were compared based on rehabilitation protocol. RESULTS: Of the163 isolated MPFL reconstructions performed during the study period, 123 (75%) were available for minimum one-year follow up at a mean of 4.0 years post-operative. Overall, 53 knees (43%) underwent the accelerated rehabilitation protocol and the remaining 70 knees (57%) underwent the restrictive protocol. There were 3 recurrent dislocations during the study period (2.4%), all of which occurred in the restrictive rehabilitation group. Multiple linear regression demonstrated that being in the accelerated rehabilitation group was not associated with poorer Knee injury and Osteoarthritis Outcome Score (KOOS) subscales controlling for age, sex, body mass index, Caton-Deschamps Index, tibial tubercle-trochlear groove distance, sulcus angle, MPFL graft choice, and length of follow-up. CONCLUSION: An accelerated rehabilitation protocol without immobilization or weightbearing restrictions does not increase risk of recurrent patellar dislocation or poorer patient-reported outcome following isolated MPFL reconstruction.

Enclavado de tibia suprapatelar, ¿por qué hemos cambiado? / Suprapatellar tibial nailing, why have we changed?

Introducción: El enclavado endomedular mediante abordaje infrapatelar (IP) se considera el gold estándar del tratamiento de las fracturas diafisarias de tibia, sin embargo, se ha asociado a mayor dificultad para la reducción y complicaciones como la mala alineación en procurvatum y al dolor anterior de rodilla. El abordaje suprapatelar (SP) surge como alternativa para solventar estos aspectos, asociándose también con un menor tiempo intraoperatorio y menor dosis y tiempo de fluoroscopia. Material y métodos: Estudio retrospectivo comparativo entre: un grupo de 22 fracturas intervenidas mediante abordaje SP y otro de 30 fracturas intervenidas por abordaje IP trastendinoso. Se analizaron variables perioperatorias y aspectos clínicos, radiológicos y funcionales en consulta a los 3, 6 y 12 meses. Resultados: No se encontraron diferencias entre grupos en cuanto a tiempo intraoperatorio, anemización, calidad de la reducción, o complicaciones en el seguimiento, entre otros. A los 12 meses, 12 (54,5%) casos SP y 16 (53,3%) IP presentaban dolor anterior de rodilla, sin diferencias significativas. En las escalas de evaluación, se registraron diferencias significativas en la IKDC (International Knee Documentation Committee) a favor de la técnica SP (88,45 [76,44-91,1] vs. IP 69 [49,95-80]) (p=0,006), sin diferencias significativas en otras escalas funcionales analizadas. Conclusiones: En consonancia con lo hasta ahora descrito en la literatura, el presente estudio apoya la tendencia hacia el enclavado SP por mejorar los resultados funcionales (IKDC) a medio plazo respecto a la técnica tradicional IP, sin aumentar las complicaciones. Asimismo se percibe por los cirujanos una mayor facilidad técnica para la reducción y sencillez en la obtención de imágenes radiológicas intraoperatorias.(AU)

Introduction: Endomedullary nailing using the infrapatellar approach (IP) is considered the gold standard for the treatment of tibial diaphyseal fractures, however, it has been associated with greater difficulty in reduction and complications such as malalignment in procurvatum and anterior knee pain. The suprapatellar approach (SP) arises as an alternative to solve these aspects, also being associated with a shorter intraoperative time and a lower dose and fluoroscopy time. Material and methods: Retrospective comparative study between a group of 22 fractures treated by SP approach and another of 30 fractures intervened by IP transtendinous approach. Perioperative variables were analyzed, as well as clinical, radiological, and functional aspects in outpatient visits at 3, 6 and 12 months. Results: No differences were found between groups in terms of intraoperative time, anemization, quality of reduction or complications during follow-up, among others. At 12 months, 12 (54.5%) SP cases and 16 (53.3%) IP presented anterior knee pain, without significant differences. In the evaluation scales, significant differences were recorded in the IKDC (International Knee Documentation Committee) in favor of the SP technique 88.45 (76.44–91.1) vs. IP 69 (49.95–80) (p=.006), with no significant differences in other functional scales analyzed. Conclusions: According to what has been described so far in the literature, the present study supports the tendency toward SP nailing by improving the functional results (IKDC) in the medium term compared to the traditional IP technique, without increasing complications. Likewise, surgeons perceive greater technical ease for reduction and simplicity in obtaining intraoperative radiological images.(AU)

Suprapatellar tibial nailing, why have we changed? / Enclavado de tibia suprapatelar, ¿por qué hemos cambiado?

Introduction: Endomedullary nailing using the infrapatellar approach (IP) is considered the gold standard for the treatment of tibial diaphyseal fractures, however, it has been associated with greater difficulty in reduction and complications such as malalignment in procurvatum and anterior knee pain. The suprapatellar approach (SP) arises as an alternative to solve these aspects, also being associated with a shorter intraoperative time and a lower dose and fluoroscopy time. Material and methods: Retrospective comparative study between a group of 22 fractures treated by SP approach and another of 30 fractures intervened by IP transtendinous approach. Perioperative variables were analyzed, as well as clinical, radiological, and functional aspects in outpatient visits at 3, 6 and 12 months. Results: No differences were found between groups in terms of intraoperative time, anemization, quality of reduction or complications during follow-up, among others. At 12 months, 12 (54.5%) SP cases and 16 (53.3%) IP presented anterior knee pain, without significant differences. In the evaluation scales, significant differences were recorded in the IKDC (International Knee Documentation Committee) in favor of the SP technique 88.45 (76.44–91.1) vs. IP 69 (49.95–80) (p=.006), with no significant differences in other functional scales analyzed. Conclusions: According to what has been described so far in the literature, the present study supports the tendency toward SP nailing by improving the functional results (IKDC) in the medium term compared to the traditional IP technique, without increasing complications. Likewise, surgeons perceive greater technical ease for reduction and simplicity in obtaining intraoperative radiological images.(AU)

Introducción: El enclavado endomedular mediante abordaje infrapatelar (IP) se considera el gold estándar del tratamiento de las fracturas diafisarias de tibia, sin embargo, se ha asociado a mayor dificultad para la reducción y complicaciones como la mala alineación en procurvatum y al dolor anterior de rodilla. El abordaje suprapatelar (SP) surge como alternativa para solventar estos aspectos, asociándose también con un menor tiempo intraoperatorio y menor dosis y tiempo de fluoroscopia. Material y métodos: Estudio retrospectivo comparativo entre: un grupo de 22 fracturas intervenidas mediante abordaje SP y otro de 30 fracturas intervenidas por abordaje IP trastendinoso. Se analizaron variables perioperatorias y aspectos clínicos, radiológicos y funcionales en consulta a los 3, 6 y 12 meses. Resultados: No se encontraron diferencias entre grupos en cuanto a tiempo intraoperatorio, anemización, calidad de la reducción, o complicaciones en el seguimiento, entre otros. A los 12 meses, 12 (54,5%) casos SP y 16 (53,3%) IP presentaban dolor anterior de rodilla, sin diferencias significativas. En las escalas de evaluación, se registraron diferencias significativas en la IKDC (International Knee Documentation Committee) a favor de la técnica SP (88,45 [76,44-91,1] vs. IP 69 [49,95-80]) (p=0,006), sin diferencias significativas en otras escalas funcionales analizadas. Conclusiones: En consonancia con lo hasta ahora descrito en la literatura, el presente estudio apoya la tendencia hacia el enclavado SP por mejorar los resultados funcionales (IKDC) a medio plazo respecto a la técnica tradicional IP, sin aumentar las complicaciones. Asimismo se percibe por los cirujanos una mayor facilidad técnica para la reducción y sencillez en la obtención de imágenes radiológicas intraoperatorias.(AU)

Medial Patellofemoral Ligament Repair with Suture Tape Augmentation: A Case Series With Five-Year Follow Up.

INTRODUCTION: The medial patellofemoral ligament (MPFL) is the main restraining force against lateral patellar displacement in the first 20 degrees of knee flexion and is often disrupted following patellar subluxation or dislocation. MPFL reconstruction is commonly performed to restore patellar stability but requires autograft harvest with associated donor site morbidity. The aim of this study was to assess the five-year outcomes of MPFL repair performed with suture tape augmentation. MATERIALS AND METHODS: All patients who underwent isolated MPFL repair for recurrent patellar instability between 2011 and 2017 were included. Patients requiring any additional surgery, such as osteotomy, were excluded. Patient-reported outcomes were measured at two-year follow up using the Knee Injury and Osteoarthritis Outcome (KOOS) Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Visual Analogue Pain Scale (VAS-pain), Veterans RAND 12-Item Health Survey (VR-12), Marx Activity Scale, and an overall satisfaction questionnaire. At the end of the study period, any complications or secondary surgeries were determined. RESULTS: Eighteen patients underwent MPFL repair with one lost to follow up. There was a significant improvement in all subscales of the KOOS scoring systems, the WOMAC functional score, and the VR-12 physical score. A significant decrease was seen in the VAS-pain score. A non-significant decrease was seen in the Marx activity scale from pre-injury. The majority of patients reported satisfaction with reduction in pain and return to sporting activities. There were no complications with no further instability episodes. CONCLUSION: This is the first study that describes the five-year follow-up results of patients treated with MPFL repair and suture tape augmentation. Our results show that this technique is an alternative treatment to traditional MPFL reconstruction with comparable outcomes and avoidance of autograft harvest.

[Patellofemoral cartilage repair]. / Therapie patellofemoraler Knorpelschäden.

Anterior knee pain is a frequent symptom in young athletes. Symptomatic patellofemoral cartilage defects can occur after trauma, especially after patellar dislocation. Numerous cartilage repair methods are currently available. Due to co-pathologies, the outcome after patellofemoral cartilage repair is inferior to the treatment of cartilage defects of the tibiofemoral joint. Adequate addressing of coexisting pathologies is essential for treatment success. This review provides an overview of the different techniques of patellofemoral cartilage repair.

Decreasing Thickness of Partial Lateral Trochlear Cartilage in Patients with Patellar Instability.

OBJECTIVE: To explore morphological characteristics of patellofemoral joint surface of patients with patellar instability by adopting the MRI-based method. METHODS: A retrospective analysis was performed from March 2016 to January 2020 to assess morphological characteristics of the patellofemoral joint surface by Magnetic Resonance Imaging (MRI) scanning knees of 30 patients (24 females, six males) with patellar instability and trochlear dysplasia and knees of 30 subjects from a randomly selected control group (25 females, five males). The control group was matched as per age and sex. All participants had undergone MRI scans in the supine position and keep knees in or near full extension. Six parts were measured in total, including thickness of trochlear cartilage, thickness of patella cartilage, cartilaginous sulcus angle, cartilaginous Wiberg angle, contact range and frequency and distributions of the mean difference measurement of the femoral trochlea, to evaluate the difference of trochlear and patellar morphology between the patient group and the control group. The threshold for statistical significance was set at P < 0.05. RESULTS: There were significant differences in four values between the two groups (P < 0.05). The cartilage thickness two-third along the lateral condyle in the patient group was significantly lower than that in the control group (LCT2,1.80 ± 0.37 vs 2.06 ± 0.52, 1.92 ± 0.36 vs 2.17 ± 0.50), but there was no significant difference in other sites. There was no significant difference in patella thickness between the patient group and the control group. The cartilaginous sulcus angle in the patient group was larger than that in the control group (157.90 ± 6.64 vs 142.23 ± 3.95, P < 0.001), but there was no significant difference in cartilaginous Wiberg angle. The patient group had a larger initial contact ratio (59.47 ± 6.13 vs 46.50 ± 3.67, P < 0.001), and a smaller contact range (16.55 ± 4.14 vs 27.55 ± 4.09, P < 0.001). The deepest part of the intercondylar suclus appears more often in the lateral of the deepest part of the osseous concavity of the femoral trochlea. Among the patient group, 18 cases (60%) were found with the deepest part of the intercondylar suclus lateral to the deepest point of the osseous concavity of the femoral trochlea while among the control group only 4 cases (13.33%) were found. The distribution of trochlear dysplasia of Dejour grades was type B (n = 22), type C (n = 5), and type D (n = 3). CONCLUSION: Thickness of partial lateral trochlear cartilage decreases in patients with patellar instability and the trochlear cartilage develops abnormal morphological characteristics. Moreover, it also suggests that MRI can be used to further present the morphology of cartilage for the convenience of surgical planning.

Medial Patellofemoral Ligament Reconstruction Using Suture Tape for Patellofemoral Joint Instability.

OBJECTIVE: To describe a surgical technique using suture tape for reconstruction of the medial patellofemoral ligament (MPFL). This technique restores the stability of the reconstructed ligament and has excellent postoperative outcomes. METHOD: This is a retrospective analysis. From January 2016 to June 2018, 17 patients underwent MPFL reconstruction using high-strength suture (FiberTape; Arthrex) augmentation, with at least 12 months of follow up. There were 11 female and 6 male patients. The mean age at the time of MPFL reconstruction was 22.1 years (range 13-34 years). Clinical outcomes included pain level, knee range of motion, passive patellar hypermobility, and maltracking at follow-up. The lateral patellofemoral angles, congruence angles, and patellar tilt angles were measured in a skyline view by CT at 30° of knee flexion at 12 months. Functional outcomes were assessed using the Lysholm knee scoring scale, the SF-12 score, the Tegner score, and the Crosby and Insall grading system at yearly follow-up. RESULT: No patients were lost at the last follow up. One patient had recurrence of patellar dislocation and none of the others had serious complications. The success rate of MPFL repair for preventing recurrent dislocations was 94.1% (16 of 17 knees). Fifteen knees had full range of motion of more than 130°. At follow-up, 2 knees were judged to have mild hypermobility and none had severe hypermobility or maltracking. Using the Crosby and Insall grading system, 12 knees (70.6%) were graded as excellent, 4 knees (23.5%) as good, 1 knee (5.9%) as fair to poor, and none as worse at the last follow-up assessment. In all patients, the Lysholm knee score (55.12 ± 13.52 vs 79.88 ± 7.50, P < 0.01), the SF-12 score (47 ± 9.53 vs 65.24 ± 12.82, P < 0.01), and the Tegner score (2.76 ± 1.39 vs 6.53 ± 1.70, P < 0.01) had improved at their 12-month follow up. Compared with preoperative radiological findings, there was a significant improvement in lateral patellofemoral angle (-10.24 ± 7.10 vs 6 ± 5.43, P < 0.01), patellar tilt angle (26.53 ± 7.23 vs 9.88 ± 4.24, P < 0.01), and congruence angle (29.59 ± 11.95 vs -8.65 ± 4.86, P < 0.01). CONCLUSION: The use of FiberTape in MPFL reconstruction can improve the stability of the knee following surgery and has good midterm clinical results and low complication rates.

Femoral Trochlear Geometry in Patients with Trochlear Dysplasia Using MRI Oblique Trochlear View.

The objective of this study was to evaluate trochlear morphology in patients with trochlear dysplasia using a new oblique trochlear magnetic resonance imaging (MRI) view (OTV) in comparison with standard axial MRI sequences. MRI exam of 73 patients with patellofemoral instability (PFI) and the same number of controls were retrospectively reviewed. The oblique trochlear sequence was acquired by inclining the axial plane parallel to the intercondylar roof of the sagittal image, showing the anterior cruciate ligament (ACL) in its entire length. Trochlear morphology was assessed on axial and oblique trochlear sequences at three levels: level 1 at 25%, level 2 at 50%, and level 3 at 75% of the length of the trochlear groove. Trochlear sulcus angle and sulcus depth were measured at these three levels and compared between the new trochlear and standard axial sequences. Trochlear sulcus angle and sulcus depth were statistically different between axial and oblique trochlear views at all three levels (p < 0,05). Additionally, OTV displayed more uniform sulcus angle and depth along the trochlea. The oblique trochlear view on the MRI can more accurately evaluate trochlear morphology and also better characterize trochlear dysplasia in patients with PFI. This is Level III, retrospective comparative study.

Systematic Review and Meta-Analysis of the Clinical Evidence on the Use of Autologous Matrix-Induced Chondrogenesis in the Knee.

OBJECTIVE: A systematic review and meta-analysis of Autologous Matrix-Induced Chondrogenesis (AMIC®) outcomes for grade III/IV chondral and osteochondral lesions of the knee treated with Chondro-Gide®. DESIGN: Studies with a minimum follow-up of 1 year providing clinical results of AMIC repair in the knee were included based on PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Methodological quality was assessed by the modified Coleman Methodology Score (mCMS). The meta-analysis was comparing pain VAS (Visual Analog Scale), Lysholm score, and IKDC score (International Knee Documentation Committee) between baseline and follow-up after 1 or 2 years and after >3 years. RESULTS: Twelve studies (375 patients) were included. The mCMS demonstrated a suboptimal study design (ranking between 52 and 80). The mean age was 36.2 years (14-70 years). The mean defect size was 4.24 cm2 (0.8-22 cm2). The results from the random effects model indicated a clinically significant (P < 0.05) improvement of pain VAS from baseline to follow-up at year 1 to 2 of -4.02(confidence interval -4.37; -3.67), still significant after 3 years. Lysholm score at year 1 or 2 improved significantly and remained highly significant after 3 years. IKDC score showed highly significant improvement of 32.61 between 1 and 2 years versus baseline values maintained after 3 years. CONCLUSIONS: The AMIC procedure significantly improved the clinical status and functional scoring versus preoperative values. Evidence was obtained in a non-selected patient population, corresponding to real-life treatment of knee chondral and osteochondral defects. The evidence is sufficient to recommend AMIC in this indication.

Prevalence of Vitamin D Insufficiency and Deficiency in Young, Female Patients With Lower Extremity Musculoskeletal Complaints.

BACKGROUND: Low levels of vitamin D have well-known impacts on bone health, but vitamin D also has a more global role throughout many tissues, including skeletal muscle. The high prevalence of hypovitaminosis D and the vast physiological features of vitamin D have led researchers to examine the influence of vitamin D on physical performance and injury. Because of the critical role of vitamin D in maintaining musculoskeletal health and function, a high rate of hypovitaminosis D among female patients with a variety of musculoskeletal issues could be of high clinical relevance. HYPOTHESIS: There is a high prevalence of low vitamin D in female patients with both acute and overuse sports-related issues of both soft tissue and bone. STUDY DESIGN: Prospective cohort study. LEVEL OF EVIDENCE: Level 3. METHODS: Female patients, aged 16 to 40 years, presenting with lower extremity injury diagnosed within the past 4 weeks, no use of multivitamin or vitamin D supplement, and no history of malabsorption syndrome met the inclusion criteria. Vitamin D levels were assessed and categorized as normal (≥32 ng/mL) and low, which includes insufficient (20.01-31.9 ng/mL) and deficient (≤20 ng/mL). RESULTS: Of the 105 patients enrolled, 65.7% had low vitamin D. Within the low vitamin D cohort, 40.6% were deficient and 59.4% were insufficient. Injuries were grouped into overuse or acute with 74 overuse injuries and 31 acute injuries, exhibiting low vitamin D prevalence of 60.8% and 77.4%, respectively. Patients with ligamentous/cartilaginous injuries exhibited the highest percentage of low vitamin D (76.5%), followed by those with patellofemoral-related complaints (71.0%), muscle/tendon injuries (54.6%), and bone stress injuries (45.5%). In univariable analysis, older age, non-White race, less physical activity, less high-intensity interval training days, less endurance training days, and more rest days showed an association with low vitamin D, but none showed an independent association in multivariable analysis. CONCLUSION: The prevalence of low vitamin D in female patients with various musculoskeletal complaints was high. Clinicians should evaluate for low vitamin D in both acute and overuse injuries. CLINICAL RELEVANCE: In addition to screening, this study suggests that clinicians should evaluate for low vitamin D levels beyond bone stress injuries in the setting of acute and overuse injuries.

Transferencia subperióstica del tendón rotuliano en pacientes esqueléticamente inmaduros con inestabilidad patelofemoral / Patellofemoral instability in skeletally immature patients. Subperiosteal transfer of the patellar tendon

El objetivo de este artículo es describir un procedimiento que puede ser aplicado en pacientes esqueléticamente inmaduros con el objetivo de realinear el aparato extensor a nivel distal. Se describe en detalle la técnica y se analizan otras alternativas terapéuticas para este escenario. Diseño del estudio: Técnica quirúrgica. Nivel de Evidencia: V

The aim of this article is to describe a procedure that can be applied in skeletally immature patients for distal realignment of the extensor mechanism. The author makes a detailed description of the technique and analyzes therapeutic alternatives for this scenario. Study design: Surgical technique. Level of Evidence: V

Reconstrucción anatómica del ligamento patelofemoral medial con aloinjerto en la luxación patelar recurrente / Medial patellofemoral ligament anatomic reconstruction with allograft in recurrent patellar dislocation

La técnica de reconstrucción del ligamento patelofemoral medial es eficaz, segura, reproducible y con baja morbilidad para el tratamiento de la luxación patelar recurrente. Los pasos a seguir son: 1) Paciente en decúbito dorsal. 2) Artroscopía diagnóstica con liberación del retináculo lateral y valoración de lesiones asociadas. 3) Incisión de 2 a 3 cm sobre el borde superomedial de la patela. 4) Realización de dos túneles de 20 a 22 mm de profundidad y 4 mm de diámetro a través del grosor de la patela bajo fluoroscopia. 5) Fijar dos anclas desde el borde medial de la patela y anudar al aloinjerto con sutura de alta resistencia. 6) Identificar el punto de Schöttle bajo fluoroscopia. 7) Incisión de 2 a 3 cm a nivel del epicóndilo medial. 8) Colocar un Kirschner de 2 mm de medial a lateral, de posterior a anterior y de distal a proximal. 9) Medir la longitud, el grosor y la tensión final deseada del aloinjerto. 10) Realizar el túnel femoral con broca canulada, 1 mm mayor al grosor del aloinjerto. 11) Utilizar el clavo con ojal para pasar la sutura y traccionar el aloinjerto de medial a lateral. 12) Fijar el aloinjerto con un tornillo biodegradable con la rodilla a 30° de flexión valorando la tensión final deseada. 13) Realizar el lavado y cierre por planos. Nivel de Evidencia: IV

The medial patellofemoral ligament reconstruction technique is effective, safe, reproducible and with low morbidity in the treatment of recurrent patellar luxation. The steps in this technique: 1) Patient in supine position. 2) Diagnostic arthroscopy with release of the lateral retinaculum and assessment of associated lesions. 3) 2 to 3 cm incision on the supero - medial border of the patella. 4) Make two tunnels 20 to 22 mm deep and 4 mm in diameter through the thickness of the patella under fluoroscopy. 5) Fix two anchors from the medial edge of the patella and tie to the allograft with high strength suture. 6) The Schöttle's point is identified under fluoroscopy. 7) 2 to 3 cm incision in the medial epicondyle. 8) A 2 mm Kirschner is placed from medial to lateral, posterior to anterior, and distal to proximal. 9) The length, thickness and desired final tension of the allograft are measured. 10) The femoral tunnel is made with a cannulated drill, 1 mm greater than the thickness of the allograft. 11) The eyelet nail is used to pass the suture and pull the allograft from medial to lateral. 12) The allograft is fixed with a biodegradable screw with the knee at 30 ° flexion, assessing the desired final tension. 13) The washing and closing are carried out by planes up to the skin. Level of Evidence: IV