DETERMINING MINIMAL DETECTABLE CHANGE AND TEST-RETEST RELIABILITY OF TIMED UP AND GO TEST, 5 TIMES SIT TO STAND TEST, 10 METERS WALK TEST, AND MAXIMAL VOLUNTARY ISOMETRIC CONTRACTION OF KNEE EXTENSORS AND FLEXORS IN PATIENTS WITH KNEE OSTEOARTHRITIS

Abstract

Introduction Timed Up and Go test (TUG), 5 Times Sit to Stand test (STS) and 10-meter Walk test (WT) are often used in clinical trials. Aim The purpose of this study is to determine the test-retest reliability of TUG, STS, 10WT and maximal voluntary isometric contraction (MVIC) of the knee extensors and flexors and to determine a minimal detectable change (MDC) for those tests in a population of patients with knee osteoarthritis (OA) who will undergo conservative treatment. Material and methods Sixty-one patients with symptomatic knee OA were included in this study. The testing protocol consisted of TUG, STS, 10WT and maximal voluntary isometric contraction (MVIC) of knee extensors and flexors. Participants were tested twice. Results TUG, STS, 10WT and MVIC and standardised MVIC of knee extensors and flexors showed an excellent test-retest reliability. Standard Error of Measurement and MDC95 for TUG was 0.37s and 1.01s, respectively; for STS was 0.69s and 1.91s, respectively; for 10WT was 0.23s and 0.65s, respectively; for MVIC of extensors was 19.66N and 54.5N, respectively; for MVIC of flexors was 9.73N and 26.96N, respectively; for standardised MVIC of extensors was 0.22 and 0.62, respectively; for standardised MVIC of flexors was 0.11 and 0.31, respectively. Conclusions TUG, STS, 10WT, and MVIC measurements have excellent test-retest reliability in mild to moderate knee OA patients. Changes greater than 1.01s for TUG, 1.91s for STS, 0.65s for 10WT, 0.62 for standardised MVIC of knee extensors and 0.31 for standardised MVIC of knee flexors may be used as clinically significant.