Abstract
The purpose of this study was to determine whether measures of impairment (i.e. muscle strength, balance), contextual factors (i.e. comorbidities, demographic information) and amputation specific variables (i.e. time since amputation, cause of amputation, level of amputation) were able to predict performance on the six-minute walk test, a measure of activity limitation, in individuals with lower limb amputation. The concept of disablement as described by the Nagi model and the ICF model were used as the basis for the study. The Guide to Physical Therapist Practice, specifically pattern J of the musculoskeletal section, impaired motor function, muscle performance, range of motion, gait, locomotion, and balance associated with amputation, was used as one model of PT diagnosis.Two subject cohorts (n = 167 and n = 72) ranging in age from 18--100 and 21--83 respectively were used in this analysis. Impairment was measured using the select items of muscle strength and balance from the Amputee Mobility Predictor. Additional strength measurements of hip extension, hip abduction, plantarflexion and hand grip were also taken. Medical comorbidities were recorded using a modified Melchiorre Index. Activity limitation was measured using the six-minute walk test.Data were analyzed and multivariate relationships were examined using multiple linear regression and forward and backward deletion processes. Bivariate relationships were examined using t-tests.The results demonstrate that the impairment variables of strength, balance, subject demographics, time since amputation, cause of amputation and level of amputation were all significant predictors of the outcome variable. This finding supports the inclusion of impairment variables in the physical therapy diagnosis to help guide interventions toward resolution of activity limitations.