What Is a Dislocated Lunate?

A dislocated lunate is an injury to the lunate bone of the wrist, in which the bone is displaced or separated completely from other wrist bones. The injury is extremely painful, and most commonly results from falls, car accidents, wrist sprains, and congenital defects. Damage can occur to other bones, muscles, blood vessels, as well as the carpal tunnel, nerves, tendons, and ligaments. The bone can be repositioned in an emergency room, but surgery is sometimes needed to correct the problem.

A primary symptom of a dislocated lunate include extreme pain. It can be painful or impossible to move the wrist or hand, and swelling and bruising may also be present. If pronounced enough, the deformity caused by the dislocation is visible if the lunate locks into a new position. Blood vessels and nerves can be cut off, so numbness, paralysis, cold sensations, and pale skin are also possible signs. When someone experiences any of these symptoms after an injury, it is important to see a doctor immediately.

The wrist joint should be immobilized with a makeshift splint, and the person should be kept warm to avoid shock. A physician can sometimes move the bones back into position. If surgery can be avoided, a dislocated lunate still takes a few weeks to heal. Ice should be used to soak the area up to four times a day, and heat treatment should be started 48 hours later. Elastic bandages should be used to wrap the wrist up and, if a cast is used, massaging can ease pain and limit the amount of swelling.

Diagnosis of a dislocated lunate in the human hand is primarily by x-ray, but a computed tomography (CT) or magnetic resonance imaging (MRI) scan requires less manipulation of the affected area. If repositioning the bone is deemed risky, then surgery is needed, which can involve placing pins through the skin to hold the wrist bones in place. Foods high in protein should be consumed during the recovery period to promote the body’s methods of healing.

It can take up to six months for a dislocated lunate to fully heal. The injury can lead to chronic problems such as arthritis, joint instability, pain, and carpal tunnel syndrome. Proper rehabilitation includes regular stretching or other exercises, which must be cleared by a physician, and activities such as driving should be avoided until the injury is healed.