Hip and knee osteoarthritis: differential pain phenotypes and evidence based management strategies for orthopedic surgeons

Abstract

Osteoarthritis (OA) of the hip and knee represents a major cause of chronic musculoskeletal pain and functional limitation worldwide. Despite shared degenerative mechanisms, these two joint disorders differ significantly in their pathophysiology, pain phenotypes, neurophysiological processes, biomechanical alterations, and therapeutic responses. This article provided a comprehensive analysis of these differences, emphasizing the implications for personalized pain management. Knee OA often presents with greater central sensitization and psychosocial comorbidity, requiring multifactorial treatment strategies, whereas hip OA demonstrates a more linear relationship between structural damage and pain. The discussion also highlighted the relevance of advanced neuroimaging, phenotypic pain classification, and targeted interventional techniques such as genicular nerve radiofrequency and robotic-assisted arthroplasty. Conservative approaches, including tailored exercise programs and weight management, remain central to care, while pharmacological and surgical interventions must be adapted to each patient's unique clinical profile. A structured, evidence-informed framework is proposed to support clinical decision-making in pain medicine, aiming to enhance outcomes and quality of life for OA patients.