Professor VHS medical center Gangdong-gu, Seoul-t'ukpyolsi, Republic of Korea
Objectives : Energy Storage and Return Foot (ESAR) systems are essential for improving gait performance in transtibial amputees. However, access to high-priced foreign ESAR feet remains limited in Korea, creating a need for domestic alternatives. A newly developed Korean ESAR integrates multiaxial ankle motion and horizontal tilt, unlike conventional foreign ESAR models restricted to sagittal movement. This study aimed to compare the biomechanical gait characteristics of the domestically developed ESAR with those of a commonly used foreign ESAR.
Design: Ten male unilateral transtibial amputees participated in this study. Each subject completed gait analysis using both a conventional foreign ESAR and the newly developed domestic ESAR in sequential order. A two-week adaptation period was provided before testing the domestic ESAR. The experimental setup included eight infrared cameras and three force plates. Nineteen reflective markers were attached to anatomical landmarks to define lower-limb segments, and spatial coordinates were calibrated using a Wand and L-frame system. Spatiotemporal parameters, joint angles, joint moments, and joint power were calculated for gait comparison. A two-way repeated-measures ANOVA was used to examine differences according to prosthesis type and limb side. Statistical Parametric Mapping (SPM) was applied to evaluate time-series differences across the gait cycle.
Results: The domestic ESAR significantly increased stride length on the affected side and improved symmetry in gait speed and stride length between limbs. SPM analysis revealed no statistically significant differences between prostheses in joint angle, moment, or power throughout the gait cycle, indicating comparable dynamic and kinematic function.
Conclusion: The domestic ESAR demonstrated gait symmetry benefits and functional equivalence to foreign ESAR models. These findings provide foundational evidence supporting its clinical application, with further studies needed for broader validation.
