Evaluation of collateral ligament injuries of the metacarpophalangeal joints with magnetic resonance imaging and magnetic resonance arthrography.

Injuries of the collateral ligaments of the metacarpophalangeal (MCP) joints of the hand require accurate diagnosis and prompt treatment to prevent loss of function. The most common and well-known collateral ligament injury is injury to the ulnar collateral ligament of the first MCP joint of the hand, often referred to as a gamekeeper injury. Although less common, injuries involving the collateral ligaments of the second through fifth digits and the radial collateral ligament of the first digit also occur. The diagnosis of collateral ligament injury is often made clinically, however, magnetic resonance imaging and magnetic resonance arthrography of the MCP joints can be very useful in the evaluation of severity of the injury. This provides important information for the hand surgeon and aids in treatment planning. Imaging of the collateral ligaments requires small fields of view and several technical considerations can provide improved image quality. These factors will be discussed and illustrated in this article.