Time Since Lower-Limb Amputation: An Important Consideration in Mobility Outcomes

Abstract

Objective: The aim of this study was to evaluate associations between time since amputation (TSAmp) and mobility outcomes of adults with lower-limb amputation.

Design: A secondary analysis of a cross-sectional dataset, including 109 community-dwelling adults, 1 yr or more after unilateral transfemoral (n = 39; mean age, 54 ± 15 yrs) or transtibial (n = 70; mean age = 58 ± 14 yrs) amputation, was conducted. Participants attended standardized clinical evaluations and completed mobility-related outcome measures: Prosthesis Evaluation Questionnaire-Mobility Subscale, timed up and go, 10-m walk test, and 6-min walk test.

Results: After controlling for age, sex, amputation level, and etiology, TSAmp was significantly associated with each mobility outcome. Prosthesis Evaluation Questionnaire-Mobility Subscale and TSAmp were linearly associated, with TSAmp explaining 10.6% of the overall variance. Timed up and go test time and TSAmp were linearly associated, with TSAmp and an interaction term (LevelxTSAmp) explaining 8.4% of the overall variance; 10-m walk test speed and 6-min walk test distance had nonlinear associations with TSAmp, with TSAmp and nonlinear terms (TSAmp2) explaining 12.1% and 13.2% of the overall variance, respectively.

Conclusions: Based on the findings, longer TSAmp may be associated with better Prosthesis Evaluation Questionnaire-Mobility Subscale score and timed up and go test time, whereas longer TSAmp may be associated with better or worse 10-m walk test speed and 6-min walk test distance depending upon time elapsed since lower-limb amputation. Estimations of postamputation mobility among adults with lower-limb amputation should consider TSAmp.