Sarcopenia and its association with pain and functional impairment in primary & secondary knee osteoarthritis, a cross-sectional study

Abstract

Background: Osteoarthritis (OA) is a prevalent degenerative joint disorder often accompanied by sarcopenia, a progressive loss of muscle mass and function. The interaction between sarcopenia, inflammation, structural joint damage, pain, nutritional status, and functional impairment remains incompletely understood. Objectives: To assess the association between sarcopenia grades and structural joint damage, pain severity, nutritional status, and functional outcomes in primary and secondary knee OA. Methods: This was a cross-sectional study including cases with primary and secondary knee OA classified according to sarcopenia severity based on EWGSOP2. Imaging findings, pain (VAS), nutritional status (MNA), and functional indices (WOMAC, Barthel Index) were assessed. Results: Severe sarcopenia was significantly associated with higher pain and lower functional independence in primary OA (p = 0.019, 0.031). No consistent associations were observed in secondary OA. Conclusion: Sarcopenia significantly impacts pain and function in knee OA, particularly in primary OA. Early identification and intervention may improve clinical outcomes.