Avoiding pitfalls in the diagnosis of the acutely injured proximal interphalangeal joint.

Closed injuries to the proximal interphalangeal joint are very common. Many anatomic structures are located in this small area; any one or several may be injured. Each causes a painful, swollen joint. A precise diagnosis of which structures are damaged is important for rational treatment. It is essential to distinguish between injuries to the flexor or extensor tendon mechanism, fractures about the proximal phalangeal joint, and ligamentous and volar plate injuries. The examining physician must understand the functional anatomy of this joint, perform a detailed evaluation, obtain the proper roentgenographic views, and render treatment according to a specific diagnosis. Accurate diagnosis with early appropriate treatment favors good recovery.