RAND 36-Item Short Form Health Research Articles

Physical Function and Properties of Quadriceps Femoris Muscle in Men With Knee Osteoarthritis

Liikavainio T, Lyytinen T, Tyrväinen E, Sipilä S, Arokoski JP. Physical function and properties of quadriceps femoris muscle in men with knee osteoarthritis. Objectives To examine the objective physical function of the lower extremities, to measure the properties of quadriceps femoris muscle (QFM), and to assess subjective disabilities in men with knee osteoarthritis (OA) and to compare the results with those obtained from age- and sex-matched control subjects. Design Cross-sectional study. Setting Rehabilitation clinic in a university hospital. Participants Male volunteers (n=54) (age range, 50–69y) with knee OA and randomly selected healthy, age- and sex-matched control subjects (n=53). Interventions Not applicable. Main Outcome Measures Physical function evaluated with a test battery including the QFM composition measurement, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the RAND 36-Item Short-Form Health Survey, version 1.0. Results Knee OA patients had 13% to 26% poorer ( P range, .050–.001) physical function and muscle strength compared with the controls. There were also significant differences in QFM composition. WOMAC ( P range, .050–.001) and muscle strength ( P<.001) associated with physical function tests, but subjective pain correlated with neither physical function nor muscle strength in knee OA patients. The radiographic knee OA grade did not have any significant effect on physical function, but passive knee motion, knee extension strength, and WOMAC were related to the severity of the disease ( P<.05). Conclusions The patients with knee OA exhibited impaired physical function and muscle strength and QFM composition compared with healthy controls. The severity of radiographic knee OA clearly had adverse effects on functional ability at the later stages of the disease. The results highlight the effect of QFM strength on physical function as well as the importance of patient's subjective and objective physical function when deciding on knee OA treatment policy.

Factors Affecting Self-Reported Pain and Physical Function in Patients With Hip Osteoarthritis

Juhakoski R, Tenhonen S, Anttonen T, Kauppinen T, Arokoski JP. Factors affecting self-reported pain and physical function in patients with hip osteoarthritis. Objective To determine the factors associated with self-reported pain and physical function in patients with hip osteoarthritis (OA). Design Cross-sectional study. Setting Rehabilitation clinic in a Finnish hospital. Participants Participants with hip OA (N=118; 35 men, 83 women; age, 66.7±6.5y; range, 55–80y). Interventions Not applicable. Main Outcome Measures Self-reported pain and self-reported disease-specific physical function were recorded by using the Western Ontario McMaster Universities Osteoarthritis Index. Self-reported generic physical function was analyzed by using the Finnish version of the RAND 36-Item Short-Form Health Survey. As listed in the International Classification of Functioning, Disability and Health model, the effects of personal factors (age, sex, education, depression, life satisfaction, smoking, years of sporting activities), pathophysiologic factors (radiologic score of hip OA, body mass index [BMI], comorbidities, duration of knee pain) and body functions and structures (measurement of leg extensor power, passive internal rotation and flexion of the hip joint, the six-minute walk test [6MWT], Timed Up & Go [TUG] test, ten-meter walk test, sock test) were analyzed. Results The educational level ( r=−.264, P<.001), comorbidities ( r=.313, P<.001), and BMI ( r=.252, P<.001) were identified as significant factors for self-reported disease-specific physical function as well as the educational level ( r=.291, P<.001), life-satisfaction ( r=−.319, P<.001), BMI ( r=−.290, P<.001), and comorbidities ( r=−.220, P<.005) for the self-reported generic physical function. No direct relationship with the pain and psychologic factors was detected. The number of comorbidities and duration of knee pain and life satisfaction explained 22% of self-reported pain. The number of comorbidities, passive hip flexion, and the TUG test explained 20% of self-reported disease-specific physical function whereas the passive hip flexion, 6MWT, and educational level explained 25% of self-reported generic physical function. Conclusions Educational level, life satisfaction, and number of comorbidities were identified as significant factors for both self-reported pain and physical functioning in hip OA. Performance measures are better predictors of physical function than pain in hip OA. Factors explaining disability and pain in hip OA are multidimensional and no single predicting factor was found to be superior to any other.