Radial Nerve Palsy

The radial nerve runs down the length of the arm. It's one of the nerves that carry signals from the brain down the arm to the hand. It controls movement of the triceps muscle at the back of the upper arm. It also controls movement and feeling in the wrist and hand. Radial nerve palsy (also called wrist drop) is caused by damage to the radial nerve. Symptoms include:

• Weakness of the wrist and fingers.

• Muscle shrinkage in the forearm.

• Pain in the arm, wrist, or hand.

• Inability to straighten the wrist or fingers.

• Numbness or tingling of the hand.

Injury to the radial nerve may be caused by:

• A direct blow to the nerve.

• A cut or other wound that affects the nerve.

• A fracture of the arm or elbow.

• Unrelieved pressure on the radial nerve (from things such as sleeping with the arm trapped under the body).

• Injury that results in swelling around the nerve.

• Use of crutches resulting in compression of the nerve.

• Long-term constriction of the wrist (for example, from a tight watch or bracelet).

• Repeated twisting motions of the forearm.

In some cases, no cause can be found.

The treatment depends on the cause and location of the nerve damage. In some cases, the problem will go away on its own once pressure to the nerve is relieved. Your health care provider may do electromyography (EMG) and nerve conduction studies (NCS) to determine the extent of damage done to the radial nerve. This will allow your provider to know a rough estimate of the time needed for you to get better. Splinting the wrist to support the fingers and wrist will help with function. If the problem is due to trauma or injury, physical therapy may be prescribed. Depending on where the nerve is injured, corticosteroid injections into the area may reduce swelling and pressure on the nerve. Surgery to repair the nerve may be needed for chronic symptoms that don't respond to simpler treatments.