Biomechanical Comparison of Novel Adaptive Swing-Phase Control Mechanical Knee Prostheses with 3R60 and 3R15 in Trans-Femoral Amputees.

Abstract

Background: The knee joint must adapt to the changes in walking speed to stabilize the stance phase and provide fluency in the swing phase.

Objective: This study aimed to report a comparison of the gait patterns of transfemoral amputees using a novel mechanical prosthetic knee that can adapt automatically to different walking speeds with 3R60 and 3R15 knee prostheses.

Material and methods: In this experimental study, biomechanical data were collected from six unilateral trans-femoral amputees walking with three knee prostheses. Gait data were gathered at slow, normal, and fast walking speeds across a 7-meter walkway using the Vicon motion system.

Results: The results revealed a significant difference in knee angular velocity during the swing phase between prosthetic knees across three walking speeds (P-value=0.002). Prosthetic knee flexion decreased significantly by increasing walking speed for the novel mechanical auto-adaptive prosthetic knee (P-value<0.001). A lower value of hip power during early swing was considered when amputees walked with novel knee prosthesis (P-value<0.00). The intact leg ankle plantar flexion angle or vaulting did not significantly change while walking speed increased in the novel knee prostheses compared to walking with the 3R60 and 3R15 knee prostheses (P-value=0.002 and P-value<0.06, respectively).

Conclusion: Based on the results, a novel mechanical auto-adaptive knee prosthesis has advantages compared to the other conventional designs for unilateral trans-femoral amputees walking at different speeds.