Abstract
Women experience greater functional impairment and occurrence of osteoarthritis than men. We hypothesized that lower levels of serum insulin-like growth factor-I may contribute to gender differences in physical impairments. A cross-sectional comparison (n = 139) was done on candidates having total knee arthroplasty and healthy control subjects of similar age (range, 55-75 years). Physical function, perceived function, and serum insulinlike growth factor levels were compared across group and gender using analysis of variance. Insulinlike growth factor-I values were markedly reduced in women overall and women having surgery had significantly reduced levels despite lean body mass correction. Values consistent with clinical hormone deficiency were observed in 21% of women and only 4% of men having arthroplasty. Physical function was markedly reduced in women, at times functioning only 33% when compared with healthy women, whereas men's limitations were not as profound. The current findings indicate that physical function is more impaired and serum insulinlike growth factor-I is markedly reduced in women awaiting arthroplasty than their male counterparts. The gender differences observed biochemically and with functional performance indicate that the pathophysiology of end stage osteoarthritis may differ between men and women.