Perilunate and lunate dislocations

[Kit]

A perilunate dislocation is disruption of the normal relationship between the lunate and capitate. A lunate dislocation is separation of the lunate from both the capitate and the radius.

(See Overview of Dislocations.)

Perilunate and lunate dislocations result when great force is applied to a hyperextended wrist. They usually result from a fall on an outstretched hand or occur in a motor vehicle crash. Perilunate dislocations are more common than lunate dislocations.

These dislocations cause pain, swelling, and deformity in the wrist and proximal hand.

If a perilunate or lunate dislocation is not diagnosed and treated promptly, complications can develop. They include

• Median nerve injury
• Avascular necrosis of the scaphoid or lunate and deterioration of the joint (scapholunate advanced collapse).