What is radial head subluxation?

Radial head subluxation means that the radius, one of two long bones in the lower arm (forearm), has pulled away from its normal position. The ligament that supports the radial bone then slips into the elbow joint. When this happens, the radial bone can't move back into its normal place.

The radius connects to the elbow joint at one end; the other end connects into the wrist joint.

What causes a radial head subluxation?

Radial head subluxation usually occurs in young children. It happens when a young child is pulled or lifted by the hand or wrist while his or her arm is held straight. For example, the bone can pull out of position, or sublux, when you try to lift a child up onto a sidewalk by the hand, pull a resistant child's hand to get him or her to move faster, or hold onto a child's hands and swing him or her around while playing.

Radial head subluxation most often occurs in young children because the socket of the elbow joint and the supporting ligaments are not fully developed. This injury is especially common in children between ages 2 and 3 years, although it can happen anytime between 6 months of age and 7 years. After age 3, children's joints and ligaments gradually grow stronger, making radial head subluxation less likely to occur.

This injury is sometimes called "nursemaid's elbow." Although physical abuse is sometimes the cause of this injury, most often a parent, caregiver, or sibling is simply playing or is trying to help or hurry a child along. But if the injury recurs often, abuse may be suspected.

What are the symptoms?

Symptoms of radial head subluxation include:

• Pain anywhere between the hand and shoulder.
• Crying. Your child may cry from the pain and because he or she feels scared.
• Refusal to move the arm. Your child may keep the arm dangling down the side of his or her body. Sometimes the dangling arm turns slightly inward (pronates).

Medical attention is needed if your child has symptoms of radial head subluxation.

How is a radial head subluxation usually diagnosed?

Your doctor usually suspects the injury from your report of how it happened, your child's symptoms, and results of the physical exam. The doctor will feel different areas of the arm and try to move it into certain positions. Usually X-rays of the elbow are not needed. But your doctor may order one to find out if your child has a more serious injury.

How is it treated?

Radial head subluxation should be treated by a health professional.

Allow your child to keep the arm in the most comfortable position until you get medical help.