Phase angle: a novel application of bioelectrical impedance technology in osteoarthritis screening and diagnosis

Bioelectrical impedance technology (EBI) offers a non-invasive, cost-effective method for body composition assessment, showing promise in diagnosing and managing musculoskeletal disorders, particularly osteoarthritis (OA). OA is a major global health concern, notably affecting the knee and hip joints. Conventional imaging techniques like X-rays and MRI have limitations in early detection, as they cannot capture microscopic cartilage changes. Phase angle (PhA), an essential EBI parameter, is widely applied in evaluating sarcopenia, tumors, and body fluids, and is increasingly valuable in OA research. PhA reflects cellular health through cell membrane impedance, with studies showing that lower PhA levels correlate with OA severity and predict OA-related degeneration, supporting its role in early screening. Additionally, EBI holds potential for monitoring OA progression and evaluating treatment efficacy. This review summarizes recent advances in OA diagnosis with EBI, focusing on the applications of PhA and other bioimpedance parameters in screening, monitoring, and evaluation. Through systematic analysis, this review provides theoretical support for EBI's clinical use, highlighting its potential in OA prevention, diagnosis, and intervention. With continued technological progress, EBI is poised to become a critical tool in OA management, particularly for early diagnosis and personalized treatment.