REDUCED MUSCLE FUNCTION IN PATIENTS WITH OSTEOARTHRITIS

The purpose of this study was to determine whether subjects with knee osteoarthritis (OA) had reduced muscle strength at various muscle leng ths, endurance, contraction velocity and functional capacity, compared with control subjects and whether the decrease was related to functio nal capacity, Forty-five men and 45 women with knee OA were compared w ith a control group (41 males, 63 females) of similar age for function al capacity, maximal isometric strength (in vivo length-tension relati onship) and endurance (in vive force-time relationship) of knee flexio n and extension and maximal angular velocity (ill vive force-velocity relationship) of knee extension, The OA subjects had increased difficu lty (2.03+/-0.53) and pain (1.65+/-0.29) for activities of daily livin g (ADLs) and significantly lower strength for extension (72%) and flex ion (56%), endurance for the quadriceps (203%) and hamstrings (214%) a nd velocity (128%), The reductions were greater at longer muscle lengt hs. These data demonstrate that patients with knee OA have reduced mus cle function and functional capacity compared to controls.