Pilot data and comprehensive literature review on ground reaction forces to guide evidence-based practice and future research on individuals with unilateral lower limb amputation

Background: Lower limb amputations (LLA) account for 74.5% of all amputations occurring in the United States. Intact limb knee pain, incidence of knee osteoarthritis (OA), and abnormal ground reaction forces (GRF) during gait are all commonly reported among individuals with LLA. Objective: The purpose of this research study is to determine if individuals with unilateral transfemoral amputation (TFA) exhibit significant differences in GRFs during gait from individuals with unilateral transtibial amputation (TTA) and to discuss the implications these potential differences may have in the development of a physical therapy plan of care. Methods: 2 male subjects with unilateral LLA (1 TTA, 1 TFA) were recruited for this study. GRFs were recorded during gait trials and compared between subject’s intact and prosthetic limb, as well as between amputation levels. Results: GRFs of the intact limbs were poorly correlated between amputation levels. TFA had increased intact limb GRFs compared to TTA for the majority of the gait cycle. Vertical and medial/lateral GRFs of the prosthetic limbs were moderately correlated between amputation levels and anterior-posterior GRFs of the prosthetic limbs were poorly correlated. Conclusion: Individuals with unilateral LLA experience greater GRFs with the intact limb. Asymmetrical GRFs of the intact limb require a physical therapy plan of care focused on therapeutic activities to equalize GRFs between limbs and decrease altered mechanics during the gait cycle.