Anatomic, radiographic and biomechanical study of the medial patellar stabilizers: medial patellofemoral ligament, medial patellotibial ligament and medial patellomeniscal ligament

INTRODUÇÃO: Os ligamentos mediais responsáveis pela manutenção da estabilidade da articulação patelofemoral (PF) são o ligamento patelofemoral medial (LPFM), o ligamento patelotibial medial (LPTM) e o ligamento patelomeniscal medial (LPMM). Sobre o LPFM, existem vários estudos anatômicos, radiológicos, biomecânicos, e a evolução clínica de sua lesão e reconstrução; no entanto, pouco se sabe sobre o LPTM e o LPMM. MÉTODOS: O LPFM, o LPTM e o LPMM foram dissecados em 9 joelhos. Todos os ligamentos foram enviados para avaliação histológica, corados pelo método de hematoxilina e eosina (HE), após o teste biomecânico. Foram medidos o comprimento e a largura bem como a relação das inserções com referências anatômicas (epicôndilo medial do fêmur, tubérculo dos adutores no fêmur, linha articular, tendão patelar e menisco medial). Esferas metálicas foram introduzidas nas inserções e radiografias em ântero-posterior (AP) e perfil (P) realizadas. Foram medidas as distâncias entre as inserções e as linhas de base (na tíbia, linha do planalto, borda medial do planalto e borda medial da espinha medial; e na patela, linha da cortical posterior e bordas proximal e distal da patela). Os ensaios de tração dos ligamentos foram executados em uma máquina de ensaios mecânicos KRATOS. RESULTADOS: Todos os materiais apresentaram tecido conjuntivo denso característico de tecido ligamentar. Com o estudo anatômico verificamos que o LPFM se encontrou na camada 2, com comprimento de 60.6 mm e largura de 15,3 mm no fêmur e 20,7 mm na patela. Inseriu-se entre o tubérculo dos adutores e o epicôndilo medial no fêmur e no pólo proximal da patela. O LPTM tinha um comprimento de 36,4 mm e largura de 7,1 mm. Sua inserção tibial se encontrou 13,7 mm distal a articulação e 11,6 mm medial ao tendão patelar formando um ângulo de 18,5o com este. A inserção na patela foi 3,6 mm proximal a sua borda distal. O LPMM se encontrou na camada 3 e seu comprimento foi de 33,7 mm e largura de 8,3 mm. Com uma inserção meniscal no corno anterior, 26,6 mm medial ao tendão patelar e formando ângulo com tendão patelar de 42,8o. Sobre os parâmetros radiográficos, a inserção tibial do LPTM se encontrou 9,4 mm, na incidência AP, e 13,5 mm, na incidência P, distal a articulação. Quanto ao posicionamento médio lateral a inserção se encontrou a 30% do comprimento do planalto de medial para lateral e na borda medial da espinha medial. A inserção patelar era 4,8 mm proximal a sua borda distal. Na análise biomecânica verificamos que o LPTM era mais rígido que o LPFM (médias de 17,0 N/mm versus 8,0 N/mm, respectivamente) e apresentou menor deformação no limite de resistência máxima (8,6 mm Resumo Betina Bremer Hinckel versus 19,3 mm). CONCLUSÃO: Os ligamentos foram identificados em todos os joelhos. Os parâmetros anatômicos e radiográficos das inserções foram bem definidos. Os enxertos comumente utilizados para as reconstruções ligamentares do joelho são suficientes para a reconstrução do LPFM e do LPTMINTRODUCTION: The medial ligaments responsible for maintaining the stability of the patellofemoral (PF) joint are the medial patellofemoral ligament (MPFL), the medial patellotibial ligament (MPTL) and the medial patellomeniscal ligament (MPML). There are several studies on the anatomical, imaging, and biomechanical characteristics of the MPFL, and clinical outcome of its injury and reconstruction; however, little is known about the MPTL and MPML. METHODS: The MPFL, MPTL and MPML were dissected in 9 knees. All ligaments underwent histological evaluation by hematoxylin eosin stain after the biomechanical test. The length and width and the insertions relationship with anatomical references (medial epicondyle of the femur, adductor tubercle of the femur, joint line, patellar tendon and medial meniscus) were measured. Steel balls were introduced at the insertions and radiographs in anteroposterior (AP) and profile (P) views were performed. The distance between the insertions to baselines were measured (in the tibia, the plateau line, the medial plateau border and the medial border of the medial tibial spine; and in the patella the posterior cortical line and the proximal and distal patellar borders). The tensile tests of the ligaments were performed on a mechanical testing machine KRATOS. RESULTS: All materials showed dense connective tissue characteristic of ligaments. With the anatomical study we found that the MPFL was in layer 2, it has length of 60.6 mm and width of 15,3 mm in the femur and 20,7 mm in the patella. Inserting between the adductor tubercle and the medial epicondyle on the femur and in the inferior pole of the patella. The MPTL was found in layer 2, its length was 36.4 mm and width of 7.1 mm. Its tibial insertion was found 13.7 mm distal to the joint line and 11.6 mm medial to the patellar tendon at an angle of 18,5o with it. On the patella it was 3.6 mm proximal to its distal border. The MPML was in layer 3 and its length was 33.7 mm and width of 8.3 mm. The meniscal insertion was in the anterior horn, 26.6 mm medial to the patellar tendon and a 42,8o angle with it. In regards to the radiographic parameters the tibial insertion of LPTM was 9.4 mm, in the AP, and 13.5 mm, in the P, distal to the joint line. The medial lateral position was at 30% from medial to lateral on the tibial plateau and on the medial edge of the medial spine. The patellar insertion was 4.8 mm proximal to the distal border of the patella. In the biomechanical analysis we verified that the MPTL was more rigid then the MPFL (average of 17.0 N / mm versus 8.0 N / mm, respectively) and showed less deformation in the maximum tensile strength (8,6 mm versus 19,3 mm). CONCLUSION: The ligaments were identified in all knees. The anatomical and radiographic insertion parameters were wel

Reconstruction of medial patellofemoral ligament using quadriceps tendon combined with reconstruction of medial patellotibial ligament using patellar tendon: initial experience

ABSTRACT OBJECTIVE: To describe a surgical technique for anatomical reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon; and to present the initial results from a case series. METHOD: The proposed technique was used on a series of cases of patients with diagnoses of patellofemoral instability and indications for surgical treatment, who were attended by the Knee Group of HC-IOT, University of São Paulo. The following were evaluated before and after the operation: range of motion (ROM), apprehension test, lateral translation test, patellar inclination test, inverted J sign, subluxation upon extension, pain from compression of the patella and pain from contraction of the quadriceps. After the operation, the patients were asked whether any new episode of dislocation had occurred, what their degree of satisfaction with the surgery was (on a scale from 0 to 10) and whether they would be prepared to go through this operation again. RESULTS: Seven knees were operated, in seven patients, with a mean follow-up of 5.46 months (±2.07). Four patients who presented apprehension before the operation did not show this after the operation. The lateral translation test became normal for all the patients, while the patellar inclination test remained positive for two patients. The patients with an inverted J sign continued to be positive for this sign. Five patients were positive for subluxation upon extension before the operation, but all patients were negative for this after the operation. None of the patients presented any new episode of dislocation of the patella. All of them stated that they were satisfied: five gave a satisfaction score of 9 and two, a score of 10. All of them said that they would undergo the operation again. Only one patient presented a postoperative complication: dehiscence of the wound. CONCLUSION: Reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon, was technically safe and presented good objective and subjective clinical results in this case series with a short follow-up

Reconstrução do ligamento patelofemoral medial com tendão quadricipital combinada com patelotibial medial com tendão patelar: experiência inicial

ResumoObjetivoDescrever técnica cirúrgica de reconstrução anatômica do LPFM com tendão quadricipital combinada com a reconstrução do LPTM com tendão patelar e apresentar os resultados iniciais em uma série de casos.MétodoFoi aplicada a técnica proposta em uma série de casos de pacientes do Grupo de Joelho do HC‐IOT diagnosticados com instabilidade patelofemoral e com indicação de tratamento cirúrgico. No pré e pós‐operatório foram avaliados: amplitude de movimento (ADM), teste da apreensão, teste da translação lateral, teste da inclinação patelar, sinal do J invertido, subluxação em extensão, dor a compressão da patela e dor a contração do quadríceps. No pós‐operatório também foi perguntado aos pacientes se houve novo episódio de luxação, qual o grau de satisfação com a cirurgia (escala de zero a 10) e se passariam pela cirurgia novamente.ResultadosForam operados sete joelhos em sete pacientes e a média de seguimento foi de 5,46 meses (±2,07). Tivemos quatro pacientes com apreensão no pré‐operatório que não tinham apreensão no pós‐operatório. O teste de translação lateral foi normalizado em todos os pacientes enquanto o teste da inclinação patelar permaneceu positivo em dois pacientes. Os pacientes com J invertido permaneceram com o sinal positivo. A subluxação em extensão, presente no pré‐operatório em cinco pacientes, foi negativa em todos no pós‐operatório. Nenhum paciente apresentou novo episódio de luxação da patela. Todos responderam estar satisfeitos. Cinco pacientes referiram satisfação 9 e dois referiram 10. Todas passariam novamente pela cirurgia. Apenas uma paciente apresentou complicação pós‐operatória, deiscência de ferida.ConclusãoA reconstrução combinada do LPFM com tendão quadricipital com a reconstrução do LPTM com tendão patelar é tecnicamente segura e apresentou bons resultados clínicos objetivos e subjetivos nesta série de caso de curto seguimento.AbstractObjectiveTo describe a surgical technique for anatomical reconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon; and to present the initial results from a case series.MethodThe proposed technique was used on a series of cases of patients with diagnoses of patellofemoral instability and indications for surgical treatment, who were attended by the Knee Group of HC‐IOT, University of São Paulo. The following were evaluated before and after the operation: range of motion (ROM), apprehension test, lateral translation test, patellar inclination test, inverted J sign, subluxation upon extension, pain from compression of the patella and pain from contraction of the quadriceps. After the operation, the patients were asked whether any new episode of dislocation had occurred, what their degree of satisfaction with the surgery was (on a scale from zero to 10) and whether they would be prepared to go through this operation again.ResultsSeven knees were operated, in seven patients, with a mean follow‐up of 5.46 months (±2.07). Four patients who presented apprehension before the operation did not show this after the operation. The lateral translation test became normal for all the patients, while the patellar inclination test remained positive for two patients. The patients with an inverted J sign continued to be positive for this sign. Five patients were positive for subluxation upon extension before the operation, but all patients were negative for this after the operation. None of the patients presented any new episode of dislocation of the patella. All of them stated that they were satisfied: five gave a satisfaction score of 9 and two, a score of 10. All of them said that they would undergo the operation again. Only one patient presented a postoperative complication: dehiscence of the wound.ConclusionReconstruction of the medial patellofemoral ligament using the quadriceps tendon, combined with reconstruction of the medial patellotibial ligament using the patellar tendon, was technically safe and presented good objective and subjective clinical results in this case series with a short follow‐up

Femoral condyle osteochondral fracture treated with bone suture after acute patellar dislocation: a case report

ABSTRACT Osteochondral fracture after acute patellar dislocation in teenagers is relatively common (up to 60% of cases of patellar dislocation), but poorly diagnosed. There are several treatments proposed for this type of injury, but none well defined in the literature.A male patient, 13 years old, with a diagnosis of osteochondral fracture of the lateral femoral condyle after acute dislocation of the right patella. He underwent surgical treatment of the chondral injury, which consisted of suturing of the chondral fragment to the cartilage defect and, in a second approach, reconstruction of the medial patellotibial ligament and medial patellofemoral ligament with autologous flexor graft. Currently, the patient has been followed up for 16 months postoperatively for the suture of the chondral fragment and for 8 months for the ligament reconstruction. He has been evaluated through functional scores and T2 weighted magnetic resonance imaging. Acute fixation through direct bone suturing of a purely chondral fragment can be considered in special situations

Translation and validation of the new version of the Knee Society Score - The 2011 KS Score - into Brazilian Portuguese

ABSTRACT OBJECTIVE: Translation, cultural adaptation, and validation of the new version of the Knee Society Score - The 2011 KS Score - into Brazilian Portuguese and verification of its measurement properties, reproducibility, and validity. In 2012, the new version of the Knee Society Score was developed and validated. This scale comprises four separate subscales: (a) objective knee score (seven items: 100 points); (b) patient satisfaction score (five items: 40 points); (c) patient expectations score (three items: 15 points); and (d) functional activity score (19 items: 100 points). METHOD: A total of 90 patients aged 55-85 years were evaluated in a clinical cross-sectional study. The pre-operative translated version was applied to patients with TKA referral, and the post-operative translated version was applied to patients who underwent TKA. Each patient answered the same questionnaire twice and was evaluated by two experts in orthopedic knee surgery. Evaluations were performed pre-operatively and three, six, or 12 months post-operatively. The reliability of the questionnaire was evaluated using the intraclass correlation coefficient (ICC) between the two applications. Internal consistency was evaluated using Cronbach's alpha. RESULTS: The ICC found no difference between the means of the pre-operative, three-month, and six-month post-operative evaluations between sub-scale items. CONCLUSION: The Brazilian Portuguese version of The 2011 KS Score is a valid and reliable instrument for objective and subjective evaluation of the functionality of Brazilian patients who undergo TKA and revision TKA

Combined Reconstruction of the Medial Patellofemoral Ligament With Quadricipital Tendon and the Medial Patellotibial Ligament With Patellar Tendon

Although the medial patellotibial ligament (MPTL) has been neglected regarding its function in patellar stability, recently, its importance in terminal extension and during flexion has been recognized. Indications for reconstruction of the medial patellofemoral ligament combined with the MPTL are extension subluxation, flexion instability, children with anatomic risk factors for patellar instability, and knee hyperextension associated with generalized laxity. We describe a combined reconstruction of the medial patellofemoral ligament with quadricipital tendon and reconstruction of the MPTL with patellar tendon autografts