Temporal–spatial parameters of gait in transfemoral amputees: Comparison of bionic and mechanically passive knee joints

Background: A symmetrical gait affords the most efficient walking pattern. Bionic prostheses should provide better gait symmetry than mechanically passive prostheses with respect to a nonpathological gait. Objectives: To compare the basic temporal–spatial parameters of gait in transfemoral amputees fitted with bionic or mechanically passive prosthetic knees with those of subjects with a nonpathological gait. Study design: Three-dimensional gait analysis using an optoelectronic device. Methods: Eight transfemoral amputees participated in the study. Subjects walked across two dynamometric platforms a total of 15 times. Movement kinematics were measured using optoelectronic stereophotogrammetry. Results: The swing time of the affected limb in patients fitted with a mechanically passive knee joint was longer than that of the nonaffected limb by 0.055 s (effect size = 1.57). Compared with the control group, the swing time of the prosthetic limb in patients fitted with a mechanically passive knee was longer by 0.042 s (effect size = 2.1). Similarly, the stance time of the nonaffected limb was longer by 0.047 s (effect size = 1.07). Conclusions: Compared with a mechanically passive knee joint, a bionic knee joint evinced gait symmetry. Both the stance time and the swing time for amputees with a bionic knee were similar to those of nonamputees. Clinical relevance Prosthetists aim to design prostheses that achieve a good symmetry between the healthy and affected limbs. The use of bionic technology achieves a level of symmetry approaching that observed in nonamputees.