Quality of Life and Functional Independence in Patients with Osteoarthritis of the Knee

PURPOSE To verify the association between functional independence (FI) and quality of life (QOL) in patients with knee osteoarthritis. MATERIALS AND METHODS A cross-sectional study composed of 93 patients with knee osteoarthritis was performed. Osteoarthritis was stratified according the classification of Ahlbach. For evaluation of the patient's overall FI, the Barthel index was used. The patient's QOL was measured by means of the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) questionnaire. RESULTS The mean age of the patients was 60 years (range, 54.0 to 69.5 years) and only 32 patients (34.3%) were found to be independent. Dependent or independent individuals presented difference in all domains of the QOL including physical function (p=0.001), role-physical (p=0.005), bodily pain (p=0.001), general health (p=0.004), vitality (p=0.009), social function (p=0.010), role-emotional (p=0.002) and mental health (p=0.001). Correlation between FI and QOL was different for all domains of the SF-36. Correlation with FI was strongest for physical function (r=0.609, p<0.001), followed by the domains of bodily pain (r=0.410, p<0.001) and mental health (r=0.402, p<0.001). CONCLUSIONS Our data demonstrated a strong association of FI with QOL and positive correlations with all QOL domains, indicating the greater the FI is, the higher the QOL is.