CESAR AUGUSTO MARTINS PEREIRA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Ortopediae Traumatologia, Faculdade de Medicina
LIM/41 - Laboratório de Investigação Médica do Sistema Músculoesquelético, Hospital das Clínicas, Faculdade de Medicina
LIM/41 - Laboratório de Investigação Médica do Sistema Músculoesquelético, Hospital das Clínicas, Faculdade de Medicina
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- Evaluation of the isometry of different points of the patella and femur for medial patellofemoral ligament reconstruction(2016) GOBBI, Riccardo Gomes; PEREIRA, Cesar Augusto Martins; SADIGURSKY, David; DEMANGE, Marco Kawamura; TIRICO, Luis Eduardo Passarelli; PECORA, Jose Ricardo; CAMANHO, Gilberto LuisBackground: The location of patellar and femoral fixation of the graft in medial patellofemoral ligament reconstructions has been widely discussed. This study aimed to assess the distances between different patellar and femoral fixation points to identify the least anisometric pairs of points. Methods: Ten cadaver knees were attached to an apparatus that simulated an active range of motion of 120, with three metallic markers fixed onto the medial side of the patella, and seven markings onto the medial epicondyle. The examined points included the proximal patella pole (1), the patellar center (3), the midpoint between points 1 and 3 (2), a point directly on the epicondyle (6), points 5 mm anterior (5) and posterior (7) to the epicondyle, points 5 mm anterior to point 5 (4) and 5 mm posterior to point 7 (8), and points 5 mm proximal (9) and distal (10) to the epicondyle. The distances between patella and femur points were measured by a photogrammetry system at 15 degrees intervals. Findings: The pair of points that exhibited the lowest average variability in distance, and hence was the most isometric, was the patella center combined with the anterior to the medial femoral epicondyle. The pairs of points that exhibited the highest average variability in distance, and hence were the least isometric, were the ones located distal or posterior to the medial femoral epicondyle, with less influence by the patellar location. Interpretation: Surgeons should avoid positioning the graft distally or posterior to the epicondyle due to the increase in anisometry.
- Biomechanical study of strength and stiffness of the knee anterolateral ligament(2016) HELITO, Camilo Partezani; BONADIO, Marcelo Batista; ROZAS, Joao Stefan; WEY, Joao Marcelo Pedroso; PEREIRA, Cesar Augusto Martins; CARDOSO, Tulio Pereira; PECORA, Jose Ricardo; CAMANHO, Gilberto Luis; DEMANGE, Marco KawamuraBackground: Recent studies clearly characterize the anatomical parameters of the knee anterolateral ligament (ALL). The potential clinical importance of this ligament is exemplified by some patients with possible combined Anterior Cruciate Ligament (ACL) and ALL rupture who do not progress satisfactorily following isolated ACL reconstruction. Previous biomechanical studies have assessed the resistance parameters of the ALL in order to address potential reconstruction strategies; however, these have reported conflicting results. Thus, this study aimed to evaluate the linear resistance of the ALL by means of a biomechanical study in cadaveric knees. Methods: Fourteen cadaveric knees were used. The ALL was dissected, and all structures that connect the femur and the tibia, except for the ALL, were sectioned. The ALL was subjected to a tensile test with the knee around 30 to 40 degrees, in a way that the ALL was aligned with the machine. The strength at the maximum resistance limit, deformation and stiffness of the ALL were evaluated. Results: The mean maximum strength of the ALL was 204.8 +/- 114.9 N. The stiffness was 41.9 +/- 25.7 N/mm and the deformation 10.3 + /- 3.5 mm. Conclusion: The ALL has a mean ultimate tensile strength of 204.8 N. This suggests that simple bands of all autologous or homologous grafts commonly used in clinical practice for ligament reconstruction around the knee possess the required biomechanical resistance characteristics for ALL reconstruction.
- Medial Patellofemoral Ligament, Medial Patellotibial Ligament, and Medial Patellomeniscal Ligament: Anatomic, Histologic, Radiographic, and Biomechanical Study(2017) HINCKEL, Betina B.; GOBBI, Riccardo G.; DEMANGE, Marco K.; PEREIRA, Cesar Augusto M.; PECORA, Jose Ricardo; NATALINO, Renato Jose M.; MIYAHIRA, Luciana; KUBOTA, Bruno S.; CAMANHO, Gilberto LuisPurpose: To describe the anatomy (quantitative macroscopic and histologic), radiographic parameters of the insertions, and biomechanical characteristics of the medial ligamentous restrictors of the patella (medial patellofemoral ligament [MPFL], medial patellotibial ligament [MPTL], and medial patellomeniscal ligament [MPML]) in cadaveric knees. Because the MPTL and the MPML are not as well known as the MPFL, they were the focus of this study. Methods: MPFLs, MPTLs, and MPMLs from 9 knees were dissected. Histologic evaluations were conducted. Length, width, and insertion relations with anatomic references were determined. Metallic spheres were introduced into the insertion points of each ligament, and anteroposterior and lateral radiographs were taken. The distances of the insertions from the baselines were measured on radiographs. Tensile tests of the ligaments were performed. Results: All the samples showed dense connective tissue characteristic of ligaments. The MPTL was inserted into the proximal tibia (13.7 mm distal to the joint line) and in the distal end of the patella (3.6 mm proximal to the distal border). The MPTL had a length of 36.4 mm and a width of 7.1 mm. The MPML was inserted into the medial meniscus and distally in the patella (5.7 mm proximal to the distal border). Per radiography, on the anteroposterior view, the tibial insertion of the MPTL was 9.4 mm distal to the joint line and in line with the medial border of the medial spine. On the lateral view, the patellar insertions of the MPTL and MPML were 4.8 and 6.6 mm proximal to its distal border, respectively. The MPTL was stiffer than the MPFL (17.0 N/mm vs 8.0 N/mm, P =.024) and showed less deformation in the maximum tensile strength (8.6 mm vs 19.3 mm, P =.005). Conclusions: The MPTL inserts into the proximal tibia and into the distal pole of the patella. The MPML inserts into the medial meniscus and into the distal pole of the patella. They present with identifiable anatomic and radiographic parameters. Grafts commonly used for ligament reconstructions should be adequate for reconstruction of the MPTL. Clinical Relevance: The study contributes to the anatomic, radiographic, and biomechanical knowledge of the MPTL to improve the outcomes of its reconstruction.
- Método de ensaio biomecânico para análise da isometricidade na reconstrução do ligamento patelofemoral medial(2012) SADIGURSKY, David; GOBBI, Riccardo Gomes; PEREIRA, César Augusto Martins; PÉCORA, José Ricardo; CAMANHO, Gilberto LuisOBJECTIVE: To present a biomechanical device for evaluating medial patellofemoral ligament (MPFL) reconstruction and its isometricity. METHODS: An accessible biomechanical method that allowed application of physiological and non-physiological forces to the knee using a mechanical arm and application of weights and counterweights was developed, so as to enable many different evaluations and have a very accurate measurement system for distances between different structures, for analysis on experiments. This article describes the assembly of this system, and suggests some practical applications. Six cadaver knees were studied. The knees were prepared in a testing machine developed at the Biomechanics Laboratory of IOT-HCFMUSP, which allowed dynamic evaluation of patellar behavior, with quantification of patellar lateralization between 0° and 120°. The differences between the distances found with and without load applied to the patella were grouped according to the graft fixation angle (0°, 30°, 60° or 90°) and knee position (intact, damaged or reconstructed). RESULTS: There was a tendency for smaller lateral displacement to occur at fixation angles greater than 30 degrees of flexion, especially between the angles of 45° and 60° degrees of flexion, after the reconstruction. For the other angles, there was no statistical significance. CONCLUSION: The method developed is a useful tool for studies on the patellofemoral joint and the MPFL, and has a very accurate measurement system for distances between different structures. It can be used in institutions with fewer resources available.