Physiological cost index (PCI) and walking performance in individuals with transfemoral prostheses compared to healthy controls

Abstract

Purpose: Uncomplicated methods for evaluation of prosthetic walking performance for individuals with lower limb amputations are valuable. The Physiological Cost Index (PCI), the comfortable walking speed (CWS) and self-reported walking distances are three examples of such measures. The aim was to obtain values for these measures for individuals walking with transfemoral prostheses and to compare the results with healthy controls.

Method: Individuals with an established transfemoral amputation for reasons other than vascular disease (TFA-group, n = 41, 30 male/11 female, mean age 49, SD 11.5) were compared to age-and gender matched healthy controls (Healthy group, n = 22). PCI was assessed walking in CWS for 5 min and self-reported distances accomplished outdoors was assessed with the Walking Habit Score (0 - 100).

Results: Mean PCI was 0.55 (SD 0.19) in the TFA-group and 0.31 (SD 0.09) in the Healthy group (p < 0.001). The CWS was 62 (SD 12.6) and 90 (SD 12.8) m/min and the Walking Habit Score 48 (SD 19) and 74 (SD 16) score-points respectively (p < 0.001).

Conclusions: By using uncomplicated and inexpensive methods, this study shows that walking with transfemoral prostheses is done with considerably increased energy cost, slower CWS and that limited walking distances outdoors are performed compared to healthy controls.