Evaluating the Stability of the Fractured Bone Implanted with Titanium Elastic Nails in C and S Configurations

Abdolreza Rastitalab, Salar Khajepour, Javad Dehghani, Ahmad Afsari, Shahin Heidari


In this paper, numerical and experimental studies have been performed on titanium intramedullary nails. S-shaped and C-shaped elastic nails have been implanted in sheep bone to compare and evaluate the mechanical axial compressive and flexural strength during loading. The purpose of this analysis is to prevent the deformity of the fracture site (closure of the gap) that may cause leg length discrepancy. A simulation process was performed to investigate the nail's mechanical response inside the bone, and the effects of pre-bending of the nails and using end caps on the bone strength were investigated. An experiment was also performed on a fractured implanted sheep bone for validation. The results showed that S-shaped symmetrical nails caused more stability under compressive and flexural loading in the fractured bone than C-shaped symmetrical nails. Increasing the pre-bending diameter of the nail caused more contact between the medullary canal and the nails, thus increasing stability. Fixing the ends of the nails at the points of entry into the medullary canal was crucial to ensure strength and prevent bone instability. In this simulation, we fixed the end of the tibia in the boundary condition, and then the loading condition was applied.

Keywords: sheep bone fracture, titanium elastic nail, finite element analysis, experimental method, S-configuration, C-configuration.

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