Finite Element Evaluation of Silicone Rubber Composites for Metacarpophalangeal Joint Implants

The metacarpophalangeal joint is one of the most important and highly mobile joints in the hand, and if it is affected by disease, it may need to be replaced with a prosthesis. However, implant fracture and mechanical degradation are important concerns. Therefore, it is important to investigate the implant’s behavior. Finite element analysis (FEA) has been widely used to study the biomechanics of joints and is an effective method to predict joint motion and failure. In this study, metacarpophalangeal joint implants made from different types of silicone rubber composites, including silica nanoparticles/silicone rubber composites, polypropylene fibers/silicone rubber composites, and a hybrid composite of silica/polypropylene fibers /silicone rubber, were simulated using Abaqus to investigate stress distribution and the range of motion of the implants under specific flexion and loading conditions. The implant was subjected to flexion up to ۷۰̊ and to a ۰.۵ N external load. The finite element analysis showed that stress in the central regions was higher than in other regions, and stress increased with increasing flexion and extension angles. Under a constant external load of ۰.۵ N, the P۲ composite exhibited the lowest displacement, strain, and stress, with values of ۳.۳۱, ۰.۱۱, and ۰.۳۳ MPa, respectively, compared with ۱۲.۹۲, ۰.۴۱, and ۰.۵۵ MPa for pure silicone. The results indicate that reinforcement of silicone rubber can substantially reduce implant deformation under load, which may contribute to a longer implant lifespan.

کلیدواژه ها:

Metacarpophalangeal joint implant ، Silicone rubber composite ، Finite element analysis (FEA) ، Abaqus