Associations Between Physical Examination and Self-Reported Physical Function in Older Community-Dwelling Adults With Knee Pain

Abstract

Background and PurposeKnee pain is a common disabling condition for which older people seek primary care. Clinicians depend on the history and physical examination to direct treatment. The purpose of this study was to examine the associations between simple physical examination tests and self-reported physical functional limitations.Subjects and MethodsA population sample of 819 older adults underwent a standardized physical examination consisting of 24 tests. Associations between the tests and self-reported physical functional limitations (Western Ontario and McMaster Universities Osteoarthritis Index physical functioning subscale [WOMAC-PF] scores) were explored.ResultsFive of the tests showed correlations with WOMAC-PF scores, corresponding to an intermediate effect (r≥.30). These were tenderness on palpation of the infrapatellar area, timed single-leg standing balance, maximal isometric quadriceps femoris muscle strength (force-generating capacity), reproduction of symptoms on patellofemoral compression, and degree of knee flexion. Each of these tests was able to account for between 7% and 13% of the variance in WOMAC-PF scores, after controlling for age, sex, and body mass index. Three of these tests are indicative of impairments that may be modifiable by exercise interventions.Discussion and ConclusionSelf-reported physical functional limitations among older people with knee pain are associated with potentially modifiable physical impairments that can be identified by simple physical examination tests.