Proprioception, dynamic balance and maximal quadriceps strength in females with knee osteoarthritis and normal control subjects

Background: Osteoarthritis (OA) is one of the most common musculoskeletal complaints worldwide. The knee is the most frequently involved joint of the lower limb in OA. Knee joint proprioception, dynamic balance and maximal quadriceps strength may be impaired in patients with knee OA. Objective: To investigate whether females with knee OA have reduced knee joint proprioception, balance responses and quadriceps strength compared with normal controls. Methods: We undertook a cross-sectional study of 30 females with knee OA and 30 controls. Knee joint proprioception was measured using electrogoniometer. Dynamic balance response was determined using a step test. Quadriceps strength was measured isometrically using a modified Tornvall chair. Results: Subjects with OA had greater mean error, poorer dynamic balance and less quadriceps strength than non-symptomatic ones (P < 0.001). Increasing age was associated with a decline in proprioceptive acuity for both controls and patients (r = 0.40, P < 0.001). In subjects with knee OA, decreased dynamic balance was associated with increasing weight (r = 0.30, P < 0.001) and reduced quadriceps strength (r = ‐0.37, P = 0.002). Conclusion: Compared with age and sex-matched controls, females with symptomatic knee OA have reduced knee proprioception, balance responses and quadriceps strength.