Difficulty delivering the baby's shoulder after the head has already come out (called shoulder dystocia)
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:
Newborn is not moving the upper or lower arm or hand
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.
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
Calling your health care provider
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.
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.
Kimberly G. Lee, MD, MSc, IBCLC, Associate Professor of Pediatrics, Division of Neonatology, Medical University of South Carolina, Charleston, SC. Review Provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.