Effect of residual volume after surgery of the discoid lateral meniscus on tibiofemoral joint biomechanics: a finite element analysis

Abstract

Background The residual volume of the discoid lateral meniscus (DLM) after surgery can vary due to various factors, and the impact of residual volume on the biomechanics of the tibiofemoral joint has been scarcely studied. This study aimed to investigate the differences in the biomechanics of the tibiofemoral joint caused by varying volumes of residual meniscus using finite element analysis. Methods A knee joint model was established based on CT and MRI imaging data. The DLM model was divided into five regions according to conventional meniscectomy, with volumes of 15%, 15%, 15%, 15%, 15%, and 40% for each region. Additionally, the DLM model was divided into anterior and posterior parts to obtain ten regions. The DLM was resected according to the design scheme, and together with the intact discoid meniscus, a total of 15 models were obtained. Finite element analysis was conducted to assess shear and pressure trends on the knee joint. Results The decrease in meniscus volume from 100–40% resulted in a gradual increase in peak compressive and shear stresses in the lateral femoral cartilage and lateral meniscus, with a significant increase at 40%. Moreover, when considering the differences in anterior and posterior volumes, meniscus models with greater preservation of the anterior volume exhibited better biomechanical advantages. Conclusion Finite element analysis suggests that preserving 85–55% of the meniscus volume should be attempted during DLM surgery. Additionally, preserving the anterior volume of the DLM is crucial for achieving better biomechanical outcomes in the knee.