A brachial plexus injury typically arises from complications during birth. The brachial plexus are a group of nerves located near the neck and shoulder. “Brachial” refers to arm and “plexus” refers to network. This group of nerves conducts signals from the spine to the hand, arm, and shoulder of the coordinating side of the body. In rare cases, a condition known as Parsonage-Turner syndrome may cause brachial plexus injury without any visible damage.
Causes of Brachial Plexus Injury
A brachial plexus injury may be the result of:
- Amniotic band syndrome
- Congenital chicken pox
- Prolonged maternal labor
- Large birth weight
- Fetal breech presentation
- Trauma prior to delivery
- Shoulder dystocia during delivery
- Birth complications resulting in attempts to adjust the fetal position
- Contact sports
- Motor vehicle accidents
- Attempts to adjust shoulder dislocation
Classifying a Brachial Plexus Injury
There are varying levels of brachial plexus injury. Some types of brachial plexus injury are more severe than others, making treatment more difficult. A brachial plexus injury is classified by defining the nature and orientation of nerve damage. In all cases, it is important to begin treatment for a brachial plexus injury as soon as possible.
The basic forms of brachial plexus injury can be classified as:
- Neuropraxia or praxis injury – This type of brachial plexus injury is the mildest. The nerves are not torn in any way, and they typically heal within a few months. Neuropraxia does not require surgery.
- Neuroma injury – This form of brachial plexus injury is moderate. Scar tissue forms around a damaged nerve, causing unnecessary pressure on the brachial plexus as the nerves try to heal. Neuromas may require surgery to remove scar tissue.
- Rupture injury – This brachial plexus injury is serious. It causes nerve tearing, but the ruptures do not occur along the spinal cord. This leaves the connection between the brachial plexus and the spinal cord intact. Ruptures will require prompt surgery and physical therapy to heal. Recovery may be full or partial.
- Avulsion injury – This is the most severe type of brachial plexus injury. The nerves of the brachial plexus tear completely away from the spinal cord. At least 90% of these cases experience severe pain. Even with surgery and physical therapy, it is difficult for avulsion injuries to adequately heal.
Signs of Brachial Plexus Injury
The following symptoms may indicate a brachial plexus injury:
- Lack of muscular control in hand, wrist, or arm
- Sensory deficits, such as lack of feeling in hand, wrist, or arm
- Weakness in arm
- Inadequate reflex abilities in arm
- Limp or paralyzed arm
Treatment Options for Infants
Depending on the exact type of brachial plexus injury, the patient’s treatment needs may vary. A neuropraxia injury should not require extensive medical attention. Neuropraxia injuries typically heal on their own, within 3 to 6 months. An infant’s ability to bend the affected arm at the elbow by 3 months of age is a good indication of future recovery. Infants with neuroma injuries are also likely to recover, but may require surgery or physical therapy to help with the healing process.
Rupture and avulsion injuries are unpromising. The chances of full recovery are diminished. Both severe types of brachial plexus injury require surgery and physical therapy. The infant should receive surgery as soon as possible. Surgical options include external neurolysis, nerve grafting, and neurotization. Physical therapy is important for the continued recovery of the infant. Actions such as raising the arm, grasping small objects, and bending the wrist will be practiced.
Effects of Brachial Plexus Injury
A brachial plexus injury may result in permanent damage involving:
- Muscular atrophy
- Horner’s syndrome
- Klumpke’s palsy
- Erb’s palsy
- Complete brachial plexus palsy
- Medical problems, such as carpal tunnel or arthritis, in unaffected arm due to doubling amount of use