Non-traumatic knee effusion is a common clinical manifestation of various musculoskeletal and inflammatory disorders, including osteoarthritis, inflammatory arthritis, and crystal-induced arthropathies. It is frequently associated with pain, functional impairment, and disease activity, yet its management is often limited to symptomatic treatment or addressed indirectly through the treatment of underlying conditions. In recent years, increasing evidence has suggested that knee effusion is not merely a secondary phenomenon but an important marker of synovial inflammation and disease progression, particularly in osteoarthritis. Current therapeutic strategies for non-traumatic knee effusion encompass pharmacological interventions, intra-articular procedures, and non-pharmacological approaches. While non-steroidal anti-inflammatory drugs, corticosteroids, and joint aspiration remain widely used to control inflammation and alleviate symptoms, their effects are often transient and associated with potential adverse events. Rehabilitation interventions, including exercise therapy, physical modalities, and biomechanical interventions, have emerged as essential components of comprehensive management by targeting joint mechanics, neuromuscular control, and synovial fluid dynamics. Advances in imaging techniques, particularly musculoskeletal ultrasound, have further facilitated the assessment and monitoring of knee effusion, enabling more individualized and targeted treatment strategies. This review provides a comprehensive overview of the etiology, pathophysiology, assessment, and management of non-traumatic knee effusion, with a particular emphasis on rehabilitation strategies. By integrating pharmacological, interventional, and rehabilitative approaches, this review highlights the importance of a multimodal and individualized management framework. Future research should prioritize standardized outcome measures for knee effusion and high-quality clinical trials to clarify the optimal role of rehabilitation in long-term disease control.

Jiaying Zhang, Yuling Bai, Juanping Xie, Chao He. Rehabilitation and therapeutic strategies for non-traumatic knee effusion: An integrative review. Academic Journal of Medicine & Health Sciences (2026), Vol. 7, Issue 4: 8-20. https://doi.org/10.25236/AJMHS.2026.070402.

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