Brachial palsy is a loss of movement or weakness of the arm caused by damage to the collection of nerves around the shoulder. This bundle of nerves is called the brachial plexus.

Brachial nerve injuries can occur during a difficult delivery. For example, it can occur if the infant's head and neck are pulled toward the side as the shoulders pass through the birth canal.

The condition can also be caused by excessive pulling on the shoulders during a head first delivery or by pressure on the 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 rotation of the lower arm.
• Klumpke paralysis affects the hand. Tthe 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
• Shoulder dystocia

Symptoms are noticed immediately or soon after birth, and may include:

• Absent Moro reflex on the affected side
• Arm flexed at elbow and held against body
• Decreased grip on the affected side
• Lack of spontaneous movement in the upper or lower arm or hand

A physical exam of the infant may show that the Moro reflex is absent on the affected side. This reflex will usually be present in an infant with weakness or pseudoparalysis, although it might not be as noticeable on the affected side. (In pseudoparalysis, the infant has a fracture and is not moving the arm because of pain.)

The affected arm may flop when the infant is rolled side to side.

A full recovery is expected in most cases. Rarely, the palsy may persist. If some strength has not returned to the affected muscles by 3-6 months of age, surgery on the nerves may restore it. Tendon transfers may also help to compensate for nerves that are not functioning properly.

Gentle massage of the arm and range of motion exercises are recommended for mild cases. More severe cases may require evaluation by several specialists.

In cases of pseudoparalysis, the child will begin to use the affected arm as the fracture heals.

Most infants recover within 6 months, but those that do not have a very poor outlook and will need further surgery to try to compensate for the nerve deficits.

Complications include permanent, partial, or total loss of function of the affected nerves, causing paralysis of the arm or arm weakness.

Call your health care provider if your newborn shows a lack of movement of either arm.

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