Influence of a concurrent cognitive task on foot pedal reaction time following traumatic, unilateral transtibial amputation
Journal of Rehabilitation Medicine
Objective: To evaluate the influence of a secondary task on foot pedal reaction time, movement time and total response time in patients with transtibial amputation. Design: Controlled trial without randomization. Subjects: Ten patients with transtibial amputation and 13 age-matched controls. Methods: Foot pedal reaction time and movement time were measured for both legs under simple and dual-task conditions. Results: While mean simple reaction time was similar for both groups (258 (standard
... (258 (standard deviation (SD) 53) vs 239 (SD 34) ms), a group by reaction time condition interaction (p < 0.05) identified a disproportionately greater mean dual-task effect among patients with transtibial amputation (432 (SD 109) vs 317 (SD 63) ms), apparently affecting the prosthetic and intact legs equally (426 (SD 110) vs 438 (SD 107) ms). Among patients with transtibial amputation faster movement time was achieved with the intact leg (185 (SD 61) vs 232 (SD 58) ms, p < 0.0001). Compared with controls, patients with transtibial amputation demonstrated impaired mean movement time (142 (SD 37) vs 208 (SD 64) ms, p < 0.001) and total response time (420 (SD 80) vs 552 (SD 151) ms, p < 0.001) regardless of reaction time condition. Conclusion: This study appears to have identified a functional manifestation of central reorganization following transtibial amputation, affecting the prosthetic and intact lower limbs equally.