RESUMO
INTRODUCTION: Treatment of proximal tibial fractures is known to be difficult. We report our own experience of the treatment of these fractures and evaluate our results. The hypothesis was that the clinical and radiological results were good. MATERIAL AND METHOD: From January 2004 to October 2008, fourteen AO-type 41A2-3 and C1 fractures have been treated with a LCP locking plate (8 women and 6 men, average age 60.42). Plating was performed either with an open approach or a minimal invasive approach. Clinical and radiological follow-up was carried out looking for range of motion of the knee joint and autonomy level. RESULTS: Mean follow-up was 32.63 months (12-70). Range of motion was maintained with a mean arch of 117.5° Autonomy was maintained in all cases. Professional, domestic and sports activities were unchanged. No infection or general complication occurred. Bone fusion was obtained in all cases after an average of 13.28 weeks. 6° of valgus deformation, already seen immediately postoperatively was observed once. Secondary displacement was observed in 6 cases, with an average of 2.83° DISCUSSION-CONCLUSION: We report good radiological results, with only one initial malalignment. The hypothesis was confirmed. However, X-ray analysis at consolidation shows 6 secondary displacements, without any satisfactory explanation. Though the clinical consequences of these malunions are minimal. Osteosynthesis with plate, in the sight of this study, yields good clinical results. Radiological evolution concerning the evolution of bone axes puts the emphasis on careful operative technique and adequate time to weight bearing. LEVEL OF EVIDENCE: retrospective study, IV.
Assuntos
Placas Ósseas , Fixação Interna de Fraturas , Radiografia , Amplitude de Movimento Articular , Fraturas da Tíbia , Humanos , Masculino , Feminino , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/fisiopatologia , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Pessoa de Meia-Idade , Resultado do Tratamento , Idoso , Seguimentos , Adulto , Consolidação da Fratura/fisiologia , Estudos Retrospectivos , Articulação do Joelho/cirurgia , Articulação do Joelho/fisiopatologiaRESUMO
INTRODUCTION: Valgus high tibial osteotomy (HTO) is indicated for managing isolated medial knee osteoarthritis in a young patient with a metaphyseal deformity of the proximal tibia. In a medial opening HTO, maintaining the integrity of the lateral hinge is crucial for ensuring proper healing and correction retention. Using a locked plate to stabilize an HTO is common practice, allowing for earlier weight-bearing. The objective of this study was therefore to measure and track the mechanical load distribution on a locked fixation plate and the lateral hinge of an HTO using a finite element (FE) model simulating single-leg stance loading. HYPOTHESIS: The working hypothesis was that during weight-bearing, the plate and the lateral hinge absorb stress asymmetrically, predominantly on the plate. MATERIAL AND METHODS: A numerical model of an HTO stabilized with a locked plate was developed based on the actual geometry of a healthy proximal tibia (using Autodesk Fusion 360 and Altair HyperWorks software). In this finite element simulation of loading, a mesh convergence study was conducted to optimize the accuracy of the numerical model results. The primary outcome measure was the maximum stress value in the affected areas (Von Mises stress, in MPa) of the plate and the lateral hinge. RESULTS: The maximum stress intensity in the plate was approximately 20.29 MPa. The maximum stress intensity in the bony hinge was about 5.6 MPa. The results of the mesh convergence study for the hinge and the plate enabled defining the most suitable model for future FE studies: a 4 mm mesh for all model elements except for the high-stress area in the plate and the hinge, which were meshed with a 0.7 mm element size. This adaptation provided greater precision in the study. DISCUSSION: There is a distribution and allocation of stress both on the plate and the hinge, underlining the significance of the plate and the absolute necessity of preserving the hinge. Predictably, the plate absorbs the majority of the load, more than three times that of the hinge. CONCLUSION: The hypothesis is confirmed; however, additional studies would be necessary to validate these numerical results: an experimental component on instrumented cadaveric bones, as well as comparative studies of different fixation plates. LEVEL OF EVIDENCE: V, expert opinion; controlled laboratory study.