Bone loss in transfemoral prosthesis users: How our everyday decisions can influence bone behaviour

There is a five-decade recorded history showing bone loss in persons with transfemoral amputation (TFA) at levels seen in bedridden and post-menopausal individuals, irrespective of age and mobility levels. These reports suggest that gait deviations, time from post-amputation to prosthetic fitting, muscle atrophy, and chemical imbalance may be factors predicting surviving femur bone loss, but the evidence to support their contributions is inconsistent.

Despite the function of a prosthesis (and prosthetic socket) to transfer ground forces to the residual limb and the role of mechanotransduction in bone health, relationship of prosthesis design to bone loss has not been studied. To our knowledge, studies have not yet quantified the effects of prosthetic socket design on the mechanical environment of the residual femur during loading. This study aimed to quantify those relationships, namely effects of ischial containment sockets (ICS) and sub-ischial sockets on bone strain, through finite element (FE) simulation of load bearing during gait.