Planar covariation of elevation angles in prosthetic gait

Area of Science:

• Biomechanics
• Neuroscience
• Prosthetics

Background:

• Transfemoral amputees require adapted coordination for effective walking.
• Prosthetic limb use necessitates complex motor control strategies.

Purpose of the Study:

• To analyze kinematic strategies in transfemoral amputees during walking.
• To investigate the coordination between the prosthetic and sound lower limbs.
• To identify potential central compensation mechanisms in amputee gait.

Main Methods:

• Utilized an opto-electronic device to record lower limb segment elevation angles.
• Applied the planar covariation of lower limb segments approach.
• Employed principal component analysis and Fourier transform for statistical analysis.

Main Results:

• The characteristic planar covariation loop was preserved in prosthetic walking for both limbs.
• A specific control over thigh elevation angle was observed, integrating other segment angles.
• Plane rotation with speed differed between control subjects, sound limb, and prosthetic limb, with reduced rotation in the prosthetic limb.

Conclusions:

• Transfemoral amputees exhibit a specific control strategy for thigh elevation during gait.
• The findings suggest a centrally commanded compensation strategy in response to amputation.
• Gait adaptation in transfemoral amputees involves distinct kinematic adjustments in the prosthetic and sound limbs.