Buckling analysis of prosthetic pylon tubes using finite element method

A pylon tube is an important component of the transtibial prosthesis which bears the weight of the patient. It influences the gait performance and comfort of the patient, where its flexibility can dictate the ground reaction forces associated with walking and step-down. Buckling is the common mode of failure. In this study, the buckling propensity of prosthetic pylon tube materials such as polypropylene (PP), titanium alloy (Ti-6Al-4V) and carbon fiber reinforced composite (CFRC) were evaluated using 3D simulation by finite element method analysis. A novel carbon fiber-pineapple fiber reinforced composite (CPFRC) material was also included as an alternative to CFRC. Parametric changes showed that the critical buckling load value for all materials increased with increasing diameter and thickness. A 120% increase in critical load was observed for both titanium alloy and CPFRC when the pylon tube length was decreased by half. Considering the price and its mechanical properties, the carbon fiber-pineapple fiber reinforced composite material can therefore be an alternative for titanium alloy or carbon fiber-based prosthetic pylon.