Overview, Causes, & Risk Factors

Brachial palsy is a condition where an infant's arm is partly or completely paralyzed at birth.

What is going on in the body?

Brachial palsy is a birth injury that can happen to newborns during delivery of the head and shoulders. The brachial plexus is a network of nerves that join together to form the nerves of the arm, hand, and fingers. If the brachial plexus is stretched during delivery, the newborn may have weakness or paralysis involving all or part of an arm.

What are the causes and risks of the condition?

The injury is more likely to happen if the baby is large and the bony outlet of the mother's pelvis is small, relative to the baby. The brachial plexus can be stretched if the person assisting in the delivery has to pull on the baby's head and neck in order to deliver the shoulders. It can also happen with breech delivery, if the baby's arms are extended above his or her head during the delivery.

Symptoms & Signs

What are the signs and symptoms of the condition?

A newborn with brachial palsy holds the affected arm close to the body. The elbow is not bent, and the hand is turned palm down. The infant cannot move the affected arm. Sometimes only the upper part of the arm is affected, and the baby can move the hand and fingers. Often the entire arm, including the hand and fingers, is affected.

Diagnosis & Tests

How is the condition diagnosed?

The healthcare provider can generally diagnose brachial palsy by observing the infant's arm position and movement. The provider may order an X-ray, CT scan, or MRI scan if a collarbone fracture is suspected.

Prevention & Expectations

What can be done to prevent the condition?

It is not easy to predict whether there is going to be difficulty delivering the baby's shoulders. If the mother is known to have a small pelvic outlet and to be carrying a large baby, the infant may be delivered by cesarean section.

What are the long-term effects of the condition?

The long-term effects of brachial palsy will vary, depending on the degree of damage to the brachial plexus. If mild damage occurs, the symptoms may improve within several days to 6 months. With severe damage, permanent paralysis may occur.

What are the risks to others?

Brachial palsy poses no risk to others.

Treatment & Monitoring

What are the treatments for the condition?

If the injury to the nerves is mild, arm and hand function usually return after several months. If the nerves are actually torn, normal function may never be recovered. Fortunately, injuries of this severity are rare. If it appears that nerve function is not returning quickly, the arm and hand can be placed in splints while the infant is sleeping to maintain the normal joint function. Range-of-motion exercises may be recommended to keep muscles strong and active.

What are the side effects of the treatments?

Splints can cause skin irritation or rash.

What happens after treatment for the condition?

A child who has full recovery from brachial palsy will need no further treatment. A child who has mild to moderate nerve damage may need physical therapy to improve use of the arm and hand. A child who has full paralysis may need periodic physical therapy to adjust to using different equipment.

How is the condition monitored?

Brachial palsy can best be monitored by the caregiver and, as the child gets older, by the child. Any new or worsening symptoms should be reported to the doctor.