Ligamentous and capsular injuries of metacarpophalangeal joints: Comprehensive analysis and clinical insights

This review provides a detailed analysis of the anatomy, mechanisms, and management of ligamentous and capsular injuries in metacarpophalangeal joints (MCPJs). The MCPJ is a condyloid joint with unique anatomical features, including a sagittal cam effect that enhances stability in flexion. Ligaments, tendons, and joint capsules contribute to the overall stability and mobility of MCPJs. The article delves into the specifics of traumatic dorsal and volar MCPJ dislocations, outlining the common mechanisms. The diagnostic methods are discussed alongside the principles of closed reduction and potential complications. Surgical approaches for both dorsal and volar dislocations are thoroughly examined. The manuscript also addresses injuries to the sagittal band, classifying them into three types and presenting conservative and surgical treatment options. Special attention is given to the diagnosis, treatment, and outcomes of isolated injuries to the joint capsule, a less common but potentially debilitating condition. Collateral ligament injuries, comprising 39 ​% of MCPJ injuries, are explored comprehensively. The article introduces a classification system for radial collateral ligament (RCL) injuries and discusses conservative and surgical management strategies based on the severity of the injury. The importance of stability in the index finger's RCL for pinch mechanism is emphasized. The review concludes with a discussion on the unique condition of the locked MCPJ, where collateral ligaments become trapped, causing joint locking. Various reduction techniques are outlined, with a focus on potential complications and the consideration of surgical correction for recurrent cases. In summary, this comprehensive review provides insights into the intricate anatomy and diverse spectrum of ligamentous and capsular injuries in finger MCPJs.