Women's Knees Are Not Gender-Neutral: A Global Scoping Review of Equity, Representation, and Context in Knee Osteoarthritis Research and Evidence.

Abstract

Women bear a disproportionate burden of knee osteoarthritis (KOA), yet global research systematically underrepresents sex-specific and context-sensitive analyses, limiting precision care and equitable interventions. We conducted a scoping review following PRISMA-ScR guidelines, systematically mapping studies on KOA in adults from 2000 to 2024 across PubMed, Embase, Scopus, Web of Science, and Cochrane Library. A predefined, version-controlled protocol was maintained with timestamped revisions and an independent audit to ensure methodological transparency. Dual independent screening, data extraction, and coding achieved high reliability (Cohen's κ = 0.87). A validated weighted gap scoring system assessed four equity domains: sex-disaggregated analysis, women's representation, contextual reporting, and geographic diversity. Integrated descriptive mapping and cross-tabulation quantified structural evidence gaps. Gray literature and non-English studies were excluded, acknowledging potential underrepresentation of low- and middle-income country (LMIC) data. Among 287 included studies, women were represented in 91%, yet only 22% were women-only cohorts, with high-income countries 2.4× more likely to conduct women-focused research than LMICs (χ² = 29.4, p < 0.001). Sex-disaggregated analyses were reported in 38% of mixed-sex studies, with profound neglect of psychosocial, preventive, and mechanistic outcomes. Intersectional analyses combining age, socioeconomic status, and context were extremely rare. Weighted gap scores highlighted very high deficiencies in SES, education, occupation, and LMIC representation, with minimal improvement over 24 years. KOA's evidence base does not merely underrepresent women; it systematically fails to generate clinically validated knowledge for them. As a result, interventions are routinely applied without clear evidence of the effectiveness across the population most affected, without mandatory sex-aggregated, mechanistic, and context-specific research.