Assessing advanced locomotor recovery after total hip arthroplasty with the timed stair test

Abstract

Objective: To assess advanced locomotor performance with the timed stair test (TST) and to determine if the level of performance of a group of women one year after hip replacement changed with the functional demands of the tasks. Design: Comparison of the performance of two groups of women. Setting: General community. Participants: A convenient sample including 18 women who had had a total hip replacement 11 months earlier (patients) and 15 healthy age-matched women (comparison group). Main outcome measures: Three tests were administered: the 10-m walk test, the unloaded TST and the loaded TST (10 kg). The duration of each test was recorded and transformed into speed and the level of performance was assessed by calculating percentage deficit using corresponding values from the comparison group. The TST is made of four subtasks: (1) standing up and walking, (2) ascending stairs, (3) turning and descending stairs, (4) walking back, turning and sitting down. Results: Significant differences in performance were found for all three tests with the patients showing a slower performance. The percentage deficits increased significantly from the less difficult (walking: 18%) to the more difficult conditions (unloaded TST: 23% and loaded TST: 28%), with the greatest deficits found during stair descent. Strong correlations were also found between walking deficits and TST deficits (loaded: r = 0.82; unloaded: r = 0.88). Conclusions: By combining mobility, walking and stair activities, the TST can be used to assess various components of advanced locomotor performance. The progressive level of difficulty of the TST subtasks as well as the addition of a load make it useful to detect subtle locomotor disabilities.