Brachial plexus injury 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.
Klumpke paralysis; Erb-Duchenne paralysis; Erb's palsy; Brachial palsy
The nerves of the brachial plexus can be injured during a difficult delivery from:
There are different forms of brachial plexus injury in an infant. The type depends on the amount of arm paralysis:
The following increase the risk of brachial plexus injury:
Brachial plexus injury is less common now that delivery techniques have improved. Cesarean delivery is used more often when there are concerns about a difficult delivery. Although a c-section reduces the risk of injury it does not prevent it, and this delivery also has other risks.
Brachial plexus injury may be confused with a condition called pseudoparalysis, in which the infant has a fracture and is not moving the arm because of pain, but there is no damage to the nerves.
Symptoms can be seen immediately or soon after birth, and may include:
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.
Gentle massage of the arm and range-of-motion exercises are recommended for mild cases. More severe cases, or those that do not improve in the first few weeks of life 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, surgery may be considered.
Most babies will fully recover within 3 to 6 months, but those who do not recover have a poor outlook. In these cases there may be a separation of the nerve root from the spinal cord (avulsion).
It is not clear whether surgery to repair the nerves or fix the nerve problem can help. Nerve grafts and nerve transfers are sometimes tried.
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.
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 plexus injury in newborn babies.
Fenichel GM. Trauma and vascular disorders. In: Fenichel GM, ed. Neonatal Neurology. 4th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2006:chap 5.
Pham CB, Kratz JR, Jelin Ac, Gelfand AA. Child neurology: brachial plexus birth injury: what every neurologist needs to know. Neurology. 2011. 77:695-697.