Brachial Plexus Injury Symptoms

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Brachial plexus injuries occur in newborns when complications during delivery stretch or tear the nerves that control the arms. Brachial plexus injury symptoms include numbness, weakness, tingling, or paralysis in the arm.

How Brachial Plexus Injuries Occur

The brachial plexus is a bundle of five major nerves that originate in the spinal cord, run through the neck, and then attach to smaller nerves in the arm.

These nerves are responsible for providing function to various parts of the arms, wrists, and hands, allowing for control of all muscle movement and sensation in those areas.[1]

If an injury causes damage to the nerves, it can interrupt movement and sensation. In a child or adult, this can happen because of some kind of traumatic injury that stretches the nerves. It can occur during contact sports, due to a fall, in a collision, or as a result of a gunshot wound, to name a few possible causes.

Infants may be born with some degree of brachial plexus injury because the head, shoulder, and neck were stretched during the descent through the birth canal.

This may happen if the person delivering the baby pulls forcibly on the arm or shoulder while the head is still in the birth canal.

It can also occur during a breech birth in which the baby’s arms are lifted above the head and, from pulling on the lower body, stretching out the neck.

Breech births, births of larger-than-average size babies, and long and difficult labors all bring a greater risk of brachial plexus injury.

Location of Symptoms

Where the symptoms of brachial plexus injury occur depends on which nerves in the bundle are damaged:

• Erb’s palsy refers to damage to the nerves that control the upper arm. In this case, the affected person will experience numbness, tingling, weakness, or paralysis in the muscles of the upper arm from the shoulder to the elbow. They may have perfectly normal sensation and movement from the elbow down to the fingers.
• Damage to the nerves that control the lower arm is called Klumpke’s paralysis or palsy. This causes symptoms anywhere between the elbow and down through the fingers. If all five nerves of the brachial plexus are damaged, the symptoms will affect the entire arm. This is called global palsy.

Symptoms of Mild Injury

A mild brachial plexus injury may feel like a shock or burning feeling running down the affected arm. This is usually followed by a sensation of numbness and weakness in the area. It can occur anywhere in the arm, from the shoulder to the fingers.

In mild cases, these symptoms usually resolve on their own in about a week (for both children and adults). For infants injured during the birth process, it generally takes about three to six months to heal and may require physical and occupational therapy.

Symptoms of Moderate to Severe Injuries

A more severe injury to the brachial plexus will cause significant weakness and, in the more severe cases, complete paralysis of one or more muscles in the arm.

There may even be paralysis of the entire arm, from shoulder to fingertips, if all the brachial plexus nerves have been badly damaged. There may also be severe pain or a complete loss of sensation due to the trauma in these more severe injuries.

Symptoms in a Newborn

Symptoms of brachial plexus injuries are similar no matter the age of the affected person, but an infant cannot tell you if they feel numb or cannot move their arm.

The symptoms of this kind of injury in a newborn must be detected by a medical professional or the parents to be properly assessed and treated.[2]

Signs to look for include:

• A weaker grip in one hand as compared to the other
• Movement in one arm, but less in the other
• An arm that is rotated toward and held against the body

Another sign is that the Moro reflex is diminished or absent on one side. Infants have a natural reflex from birth, which usually disappears by about three or four months of age. To test this reflex, the baby is placed on its back.

The arms are gently lifted and then let go together. This gives the feeling of falling, and the baby should appear startled during this maneuver, extending the arms outward first, then to the front, and finally back again to the sides.

This predictable movement is called the Moro reflex, and it should be symmetrical. Diminished or absent movement on one side is often an indication of brachial plexus injury.[3]

Horner’s Syndrome

A rare complication of brachial plexus damage is called Horner’s syndrome. The symptoms in this condition include pupil constriction in one eye, drooping of one eyelid, and an inability to sweat on one half of the face.

These are rare symptoms, but they result from damage to nerves in the part of the brachial plexus that includes nerves going to the face and eyes.

Prognosis

The outlook for a brachial plexus injury depends on the severity of the damage to the nerves. The impairment is only mild for most infants and will heal within three to six months of birth. In these cases, the child should not experience any symptoms once the nerves have healed.

More treatment may be needed for more severe injuries, including those in which the nerves are torn, including surgery to repair damaged nerves.

If your child shows signs of brachial plexus damage, talk to your pediatrician right away. Then speak to a birth injury lawyer to determine your legal options.