To review findings on sex differences in cartilage anatomy, cartilage imaging, and treatment in osteoarthritis, based on an invited presentation held at the International Workshop of Osteoarthritis Imaging (IWOAI) 2025. A non-systematic literature search (Pubmed) and consultations with experts. Additionally, comparative radiographic joint space width (JSW) and femorotibial cartilage thickness data were obtained from 2396 knees (from 2004 male and female Osteoarthritis Initiative participants), covering radiographic joint space narrowing (JSN) grades 0-3. Sex differences in JSW and cartilage morphology were related to those of other articular and periarticular tissues in qualitative form. Men displayed greater JSW and femorotibial cartilage thickness than women. For JSW, but not for cartilage thickness, sex differences disappeared with greater joint space narrowing (JSN) grade. The sex difference in cartilage thickness was maintained after adjusting for relevant covariates, e.g. body height. These morphological findings differ from those in cartilage transverse relaxation time (T2) and from other (peri-) articular tissues. Preliminary findings suggest that men may respond more strongly to surgical and anabolic pharmacological cartilage therapy. Between and within species, large differences exist in the heterogeneity of morphological traits. Sexual dimorphism can be male- or female biased in different species; within humans some musculoskeletal characteristics are greater in men and others in women. Men display “genuinely” greater JSW, cartilage thickness, and joint surface areas than women, the latter potentially contributing to a lower joint pressure and lower incidence in knee osteoarthritis than in women. Sex-differences in cartilage treatment response deserve deeper exploration.
F Eckstein (Fri,) studied this question.