Brachial Plexus

The brachial plexus is a group of nerves that run from the lower neck through the shoulder and upper arm area. These nerves control movement and sensation in the shoulder, arm, forearm and hand.

Brachial plexus injury occurs when the nerves around the neck and shoulder area are harmed. This damage can make it impossible to move or feel the shoulder, arm, forearm or hand.

Call 832-822-3180 to schedule an appointment. 

Patients can be seen by Texas Children's experts in Peripheral Nerve Clinic and Physical Medicine and Rehabilitation.

Causes & Risk Factors

Causes or risk factors include:

• Shoulder dystocia.  If the baby's shoulder becomes lodged against the mother's pelvis during childbirth, labor can be prolonged and marked by too much stretch and trauma of the brachial plexus. 
• Inflammation
• Trauma
• Tumor

Causes in children and adolescents include:

• Inflammation. A rare condition known as Parsonage-Turner syndrome (brachial plexitis) can occur because of a viral illness and lead to inflammation of the brachial plexus.
• Trauma from accidents on bicycles or ATVs or from sports injuries.
• Tumors of the nerves themselves or the surrounding structures can damage nearby tissue or place too much pressure on the brachial plexus.

Symptoms & Types

Symptoms of an injury during childbirth can be seen immediately or soon after birth, and may include: 

• Newborn is not moving the shoulder, arm, forearm, or hand. 
• The baby shows no signs of the Moro reflex: this is when the baby arches its back, extends the arms and legs and cries when exposed to loud noise or sudden movement. 
• Arm bent at elbow and held against body. 
• Decreased grip on the affected side. 

Symptoms in children and adolescents may include: 

• A limp or paralyzed arm. 
• Lack of muscle control in the arm, hand or wrist. 
• Lack of feeling or sensation in the arm or hand. 

Types of damage:  

The type of damage to the nerves determines the seriousness of the injury.  

    Neuropraxia (also called stretch injury):

• Neuropraxia damages the protective covering of the nerve (called myelin) but does not always damage the nerve itself.  This injury causes problems with the ability of nerves to signal the body.  
• This is the mildest form of injury and can resolve on its own.  

    Rupture (also called post-ganglionic injury): 

• Caused when the nerve root breaks and is no longer in continuity.  
• This is a moderate form of injury.

    Avulsion (also called pre-ganglionic injury): 

• Caused when the nerve root is pulled directly off the spinal cord. 
• This is the severest form of injury.   

Diagnosis & Tests

The doctor will examine the shoulder, arm, wrist and hand. Some signs that the nerve may be injured include: 

• Abnormal posture of the shoulder, arm, forearm, wrist, or hand.
• Decreased size or strength of the muscles of the upper part of the body.
• Weakened reflexes in the arm.
• Difficulty in moving the arm, shoulder, hand or fingers.

Depending on the results of a physical examination, tests may include:

• Magnetic resonance imaging (MRI) to get a detailed picture of the spinal cord and nerve roots and to get information on the type of nerve injury.
• Computerized tomography (CT) to better evaluate shoulder anatomy and structure in the older child.
• Nerve conduction studies to provide information about how well a nerve is working.
• Electromyography (EMG) to evaluate electrical activity of the muscles when they contract and when they are at rest.

Treatment & Care

Treatment may include one or more of the following: 

• Physical therapy
• Splinting
• Botox shots
• Surgery 

Injuries caused by neuropraxia (stretch injury): 

• Up to a 90% chance for spontaneous recovery, without the need for surgery.
• Generally, physical therapy and splinting are the main ways to treat this injury.  Tight muscles can sometimes prevent further gains in motion and can be relaxed with Botox shots. 

Injuries caused by rupture or avulsion (avulsion is separation of the nerve):   

• The possibility of function returning on its own is low.
• Successful recovery generally requires surgery in a timely manner after the injury to restore the nerve.

Living & Managing

In children with brachial plexus injuries, day-to-day living should include: 

• A routine set of exercises to maintain shoulder, elbow, wrist and hand joint range of motion and to strengthen the regenerating muscles.

Parents should pay particular attention to their child's activity level and let the care team know if there is a significant drop-off.

Parents should be reassured to know that children are quite adaptive when they face upper extremity weakness on one side of their body and they generally maintain a high level of ability to function.