Gender differences in the correlation between symptom and radiographic severity in patients with knee osteoarthritis.

Background: The effects of gender on the relationship between symptom manifestations and radiographic grades of knee osteoarthritis are not well understood.

Questions/purposes: We therefore determined the increments of symptom progression with regard to radiographic grades of knee osteoarthritis and asked if those increments differed by gender and whether symptom severity was differentially manifested by gender within the same grade.

Methods: We recruited 660 community residents; 368 (56%) women and 292 (44%) men. The mean subject age was 71.5 years (range, 65-91 years). Severity of symptoms was measured using the WOMAC and SF-36 scales, and the radiographic severity using Kellgren-Lawrence grades. Incremental changes in WOMAC and SF-36 scores were compared between adjacent Kellgren-Lawrence grades separately in men and women, and in the overall population. We compared symptom severity between men and women with the same radiographic grade.

Results: For the entire cohort, the mean incremental change in symptom severity was not gradual between the adjacent radiographic grades but was greater between Kellgren-Lawrence Grades 1 and 2 and Grades 2 and 3 than between Grades 0 and 1 or Grades 3 and 4. The patterns of incremental changes in symptom severity differed between men and women: women had more severe symptom progression between Kellgren-Lawrence Grades 2 and 3 and Grades 3 and 4 than men. Furthermore, women had worse mean WOMAC and SF-36 scores than men with the same radiographic grade of knee osteoarthritis.

Conclusions: These data suggest symptom progression is not gradual between adjacent radiographic grades, and for the same radiographic grade, symptoms are worse in women.

Level Of Evidence: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.