Figure 1. Anteroposterior radiograph of the right hand.
Figure 2. Lateral radiograph of the right hand.
A 45-year-old man presents to the office after sustaining a dislocation in his right small finger 1 week ago. He was playing tennis when he fell and struck the finger. Anteroposterior and lateral radiographs of the right hand (Figures 1 and 2) show a proximal interphalangeal (PIP) joint dislocation. The finger was reduced and splinted in the emergency department.
What is the next best step in treatment?
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The PIP joint is the most commonly injured joint in the hand.1 Injuries of the PIP joint can range from ligament sprains, middle and proximal phalanx fractures, and dislocations. The PIP joint is supported by collateral ligaments, a joint capsule, and a volar plate. The volar plate is a thick, ligamentous structure that prevents hyperextension of the joint. The PIP joint can dislocate in a dorsal, volar, and lateral direction. The dislocation is described by the relationship of the middle phalanx to the proximal phalanx. For example, a hyperextended finger can dislocate the middle phalanx dorsally as the proximal phalanx dislocates in a volar direction. This type of dislocation is described as a dorsal dislocation of the PIP joint, which is the most common type. When the finger is hyperextended, the volar plate can fail and result in dislocation. A PIP joint dislocation can be repaired with closed reduction and traction and may not require local or general anesthesia. Early motion after dislocation of a PIP joint is critical to prevent finger stiffness. Treatment should involve splinting the finger for ≤1 week followed by buddy taping and early motion.1,2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor-in-chief of the Journal of Orthopedics for Physician Assistants (JOPA).
1. Borcher JR, Best TM. Common finger fractures and dislocations. Am Fam Physician. 2012;85(8):805-810.
2. Elfar J, Mann T. Fracture-dislocations of the proximal interphalangeal joint. J Am Acad Orthop Surg. 2013;21(2):88-98.