What is Lunate Dislocation

Lunate dislocation is an injury in which one of the wrist bones (lunate bone) is moved out of its normal position. The lunate bone is one of the eight small bones in the wrist. It is located near the end of the outer forearm bone (ulna).

Dislocation of the lunate is usually caused by having the hand pushed backward with a great deal of force. Treatment is urgent. It may start with putting the bone back in place without surgery (closed reduction) and applying a splint. In most cases, surgery will also be needed to prevent problems such as arthritis or nerve damage.

What are the causes?

This injury is usually caused by falling on the palm of the hand while the arm is outstretched or extended. The fall forces the hand backward (hyperextension), which causes the dislocation. This injury may also occur if you are in a motor vehicle accident and the palm of your hand is forced backward.

What increases the risk?

The following factors may make you more likely to develop this injury:

• Participating in activities that may result in serious falls, such as skateboarding, gymnastics, or snowboarding.
• Older age. Elderly people have a higher risk of falling.

What are the signs or symptoms?

Symptoms of this injury include:

• Pain, especially when moving the wrist or fingers.
• Swelling.
• Change in appearance of the wrist (deformity).
• Numbness or tingling in the fingers.

How is this diagnosed?

This injury may be diagnosed based on:

• Your description of the injury.
• A physical exam of your hand and wrist.
• X-rays of the wrist.
• A CT scan to check for any injuries in the surrounding area.

How is this treated?

Treatment for this injury may include:

• Closed reduction. This is usually the first treatment in the emergency room. Your bone is pushed back into place without surgery.
• Surgery. You may need to see a hand specialist (orthopedist) for a surgical repair that is called open reduction with internal fixation (ORIF). This is usually needed to prevent related problems and to restore movement. ORIF involves opening your wrist and placing wires or pins to hold the lunate bone in place.
• Wearing a splint or cast to hold the bone in place after closed reduction or surgery.
• Doing exercises to help restore movement in your wrist. A physical therapist may direct this part of your recovery.

Follow these instructions at home:

If you have a cast:

• Do not stick anything inside the cast to scratch your skin. Doing that increases your risk of infection.
• Check the skin around the cast every day. Report any concerns to your health care provider. You may put lotion on dry skin around the edges of the cast. Do not apply lotion to the skin underneath the cast.
• Do not let your cast get wet if it is not waterproof.
• Keep the cast clean.

If you have a splint:

• Wear the splint as told by your health care provider. Remove it only as told by your health care provider.
• Loosen the splint if your fingers tingle, become numb, or turn cold and blue.
• Do not let your splint get wet if it is not waterproof.
• Keep the splint clean.

Bathing

• Do not take baths, swim, or use a hot tub until your health care provider approves. Ask your health care provider if you can take showers. You may only be allowed to take sponge baths for bathing.
• If your cast or splint is not waterproof, cover it with a watertight plastic bag when you take a bath or a shower.

Managing pain, stiffness, and swelling

• If directed, apply ice to the injured area.
  • Put ice in a plastic bag.
  • Place a towel between your skin and the bag.
  • Leave the ice on for 20 minutes, 2–3 times per day.
• Move your fingers often to avoid stiffness and to lessen swelling.
• Raise (elevate) the injured area above the level of your heart while you are sitting or lying down.

Driving

• Do not drive or operate heavy machinery while taking prescription pain medicine.
• Ask your health care provider when it is safe to drive if you have a cast or splint on a hand that you use for driving.

Activity

• Return to your normal activities as told by your health care provider. Ask your health care provider what activities are safe for you.
• Do exercises as told by your health care provider.

General instructions

• Do not put pressure on any part of the cast or splint until it is fully hardened. This may take several hours.
• Take over-the-counter and prescription medicines only as told by your health care provider.
• Do not use any tobacco products, including cigarettes, chewing tobacco, or e-cigarettes. Tobacco can delay bone healing. If you need help quitting, ask your health care provider.
• Keep all follow-up visits as told by your health care provider. This is important.

How is this prevented?

• Maintain physical fitness, including wrist strength and flexibility.
• Use taping, braces, or wrist guards when you participate in sports.

Contact a health care provider if:

• Your pain or swelling gets worse even though you have had treatment.
• Your cast or splint becomes loose or damaged.

Get help right away if:

• You have pain, numbness, or coldness in your hand or fingers.
• Your fingers or fingernails turn blue or gray.
• You lose feeling in your hand or fingers.