Kinematic differences exist between transtibial amputee fallers and non-fallers during downwards step transitioning

摘要

Background: Stair negotiation is biomechanically more challenging than level gait. There are few biomechanical assessments of transtibial amputees descending stairs and none specifically related to falls. Stair descent may elicit more differences than level gait in amputees with and without a previous falls history. Objectives: The aim of this study was to compare the gait kinematics of fallers and non-fallers during downwards step transitioning in transtibial amputees. Study design: Cross-sectional study. Methods: Six fallers and five non-fallers completed step transition trials on a three-step staircase at their self-selected pace. Results: Nine participants exhibited a clear preference to lead with the affected limb, while two had no preference. Four participants self-selected a step-to rather than a reciprocal stair descent strategy. The fallers who used a reciprocal strategy walked 44% more quickly than the non-fallers. To compensate for the lack of active plantar flexion of the prosthetic foot, exaggerated range of motion occurred proximally at the pelvis during swing. The step-to group was more reliant on the handrails than the reciprocal group and walked more slowly. Conclusion: As anticipated, the fallers walked faster than the non-fallers despite employing the more difficult 'roll-over' technique. Handrail use could help to improve dynamic control during downwards step transitions. Clinical relevance Transtibial amputees are advised to descend steps using external support, such as handrails, for enhanced dynamic control. Hip abductor and knee extensor eccentric strength should be improved through targeted exercise. Prosthetic socket fit should be checked to allow adequate knee range of motion on the affected side. © 2014 The International Society for Prosthetics and Orthotics.