Objective: To determine if subjects can offload the right lower extremity to a targeted amount of weight bearing using assistive devices.
Design: Case series.
Setting: Motion analysis laboratory.
Participants: Ten healthy subjects (5 men, 5 women) without lower-extremity injury and minimal experience using ambulatory aids.
Interventions: Before data collection subjects were trained by a physical therapist to offload the right lower extremity by 50% by using an assistive device and a bathroom scale for feedback on weight reduction.
Main outcome measures: Vertical ground reaction force was measured by using forceplates while subjects walked at a self-selected speed by using a 3-point partial weight-bearing (PWB) gait pattern with axillary crutches, forearm crutches, and wheeled walker. We also measured vertical ground reaction force by using a single-point cane.
Results: Each gait aid significantly reduced the right lower-extremity peak vertical ground reaction force. Participants were able to achieve the target of approximately 50% weight reduction with the axillary (50% reduction) and forearm (56% reduction) crutches. The wheeled walker resulted in a peak vertical load of 64% of body weight, which was in excess of the target load. A single-point cane produced a peak vertical load of 76% of body weight.
Conclusions: By using a bathroom scale, healthy subjects could be trained to achieve a target goal of 50% PWB with axillary and forearm crutches. A wheeled walker resulted in weight bearing greater than the target of 50% of body weight. Subjects were able to offload the right lower extremity by about 25% of body weight by using a single-point cane.