BRACHIAL PALSY

Brachial palsy is a loss of movement or weakness of the arm that occurs when the collection of nerves around the shoulder are damaged during birth.

This bundle of nerves is called the brachial plexus.

Causes

The nerves of the brachial plexus can be injured during a difficult delivery from:

• The infant's head and neck pulling toward the side as the shoulders pass through the birth canal
• Pulling on the shoulders during a head-first delivery
• Pressure on the baby's raised arms during a breech (feet first) delivery

There are different forms of brachial palsy in an infant. The type depends on the degree of arm paralysis:

• Brachial plexus injuries typically affect only the upper arm.
• Erb's paralysis affects the upper arm and lower arm.
• Klumpke paralysis affects the hand. The infant may also have an eyelid droop on the opposite side.

The following increase the risk of brachial palsy:

• Breech delivery
• Larger than average newborn (such as an infant of a diabetic mother)
• Difficulty delivering the baby's shoulder after the head has already emerged (called shoulder dystocia)

Brachial palsy is less common now that delivery techniques have improved. Cesarean delivery is used more often when there are concerns about a difficult delivery.

Brachial palsy may be confused with a condition called pseudoparalysis. The infant has a fracture and is not moving the arm because of pain, but there has been no damage to the nerves.

Symptoms

Symptoms can be seen immediately or soon after birth, and may include:

• Newborn is not moving the upper or lower arm or hand
• Absent Moro reflex on the affected side
• Arm flexed (bent) at elbow and held against body
• Decreased grip on the affected side

Exams and Tests

A physical exam usually shows that the infant is not moving the upper or lower arm or hand. The affected arm may flop when the infant is rolled from side to side.

The Moro reflex is absent on the side with the brachial plexus or nerve injury.

A careful examination of the clavicle or collarbone will be done to look for a fracture. Sometimes, the infant will need to have an x-ray of this bone.

Treatment

Gentle massage of the arm and range of motion exercises are recommended for mild cases. More severe cases may need to be evaluated by several specialists.

If some strength has not returned to the affected muscles by the time the baby is 3 - 6 months old, treatments may include:

• Surgery on the nerves
• Tendon transfers to help the muscles that are affected by nerve damage work better

Outlook (Prognosis)

A full recovery is expected in most cases. Most infants recover within 6 months, but those that do not recover have a very poor outlook.

The benefit of surgery to try to repair the nerves or compensate for the nerve deficit is not clear.

In cases of pseudoparalysis, the child will begin to use the affected arm as the fracture heals. Fractures in infants usually heal very quickly and easily.

Possible Complications

Complications include:

• Abnormal muscle contractions (contractures) or tightening of the muscles, which may be permanent
• Permanent, partial, or total loss of function of the affected nerves, causing paralysis of the arm or arm weakness

Prevention

Taking measures to avoid a difficult delivery, whenever possible, reduces the risk of brachial palsy in newborn babies.