Lower limb kinematics and kinetics of people with through-knee amputation compared to individuals with transfemoral amputation and able-bodied controls during walking

Lower-limb amputations negatively affect quality of life and increase the risk of secondary health conditions. Through-Knee Amputation (TKA), although less commonly performed than Transfemoral Amputation (TFA), offers potential biomechanical advantages due to preserved femur length and associated musculature. This study aimed to characterize gait biomechanics of individuals with unilateral TKA, TFA and able-bodied controls. Gait biomechanics of seven individuals with unilateral TFA, four with unilateral TKA, and nine able-bodied controls were evaluated with a 3D motion tracking system and force plates. Joint angles and moments at the ankle, knee, hip, and pelvis were computed and compared between groups. Individuals with TKA's walking mechanics displayed fewer differences with able bodied controls compared to individuals with TFA. Individuals with TKA had greater hip Range Of Motion (ROM) on the amputated side than TFA (52.71° ± 7.3°, 40.38° ± 5.4° respectively, p < 0.005). TFA individuals had higher pelvic antero/posterior tilt ROM compared to controls (11.26° ± 7.2° and 3.1° ± 1.5° respectively, p < 0.005) but TKA and controls were not statistically different from each other. TKA individuals and able-bodied controls both had lower peak hip extension moments on the intact side than individuals with TFA (1.05 (±0.43), 1.05 (±0.39) and 1.83 (±0.28) N.m.kg^-1, p < 0.005, p < 0.05 respectively). These findings suggest that TKA may offer biomechanical advantages over TFA, particularly in preserving gait biomechanics closer to able-bodied controls, underscoring the potential advantages of this procedure for individuals requiring lower-limb amputation.