Brachial Plexus Injury: Types and Prognosis

Brachial Plexus Injury Overview

A brachial plexus injury is an injury to the brachial plexus the network of nerves that sends signals from your spine to your shoulder, arm and hand.

A brachial plexus injury occurs when these nerves are stretched, compressed or, in the most serious cases, torn. This can happen when your shoulder is pressed down forcefully while your head is pushed up and away from that shoulder; a direct contact hit also can compress these nerves.

Brachial plexus injuries are common in contact sports such as football, but they can also result from auto or motorcycle accidents or falls. Babies sometimes sustain brachial plexus injuries during birth. Other conditions, such as inflammation or tumors, may affect the brachial plexus.

Minor injuries may get better on their own, but severe brachial plexus injuries require surgical repair.

Causes of a Brachial Plexus Injury

Brachial plexus injury (BPI) is an umbrella term for a variety of conditions that may impair function of the brachial plexus nerve network. The majority of pediatric and adult brachial plexus injuries are caused by trauma. The most common inciting events may include:

• High-speed vehicular accidents, especially motorcycle accidents
• Blunt trauma
• Stab or gunshot wounds
• Inflammatory processes (brachial plexitis)
• Compression (for example caused by a growing tumor)
• Neuropathies

A brachial plexus injury occurring during birth is called birth related brachial plexus palsy or obstetric brachial plexus palsy.

Brachial Plexus Injury Symptoms

Signs and symptoms of a brachial plexus injury can vary greatly, depending on the severity and location of your injury. Usually only one arm is affected.

Less severe injuries

Minor damage often occurs during contact sports, such as football or wrestling, when the brachial plexus nerves get stretched or compressed. Known as stingers or burners, these injuries can produce the following symptoms:

• A feeling like an electric shock or a burning sensation shooting down your arm
• Numbness and weakness in your arm

These symptoms usually last only a few seconds or minutes, but in some people may linger for days or longer.

More-severe injuries

More-severe symptoms result from injuries that seriously injure or even tear or rupture the nerves. The most serious brachial plexus injury (avulsion) occurs when the nerve root is torn from the spinal cord.

Signs and symptoms of more-severe injuries can include:

• Weakness or inability to use certain muscles in your hand, arm or shoulder
• Complete lack of movement and feeling in your arm, including your shoulder and hand
• Severe pain

What is the prognosis?

The site and type of brachial plexus injury determines the prognosis. For avulsion and rupture injuries, there is no potential for recovery unless surgical reconnection is made in a timely manner. The potential for recovery varies for neuroma and neuropraxia injuries. Most individuals with neuropraxia injuries recover spontaneously with a 90-100% return of function.

Types of Brachial Plexus Injuries

Brachial plexus injuries are categorized according to the type of trauma experienced by the nerve. The following are the types of brachial plexus injuries:

• Avulsion : this means the nerve has been pulled out from the spinal cord and has no chance to recover.
• Rupture : this means the nerve has been stretched and at least partially torn, but not at the spinal cord.
• Neurapraxia : this means the nerve has been gently stretched or compressed but is still attached (not torn) and has excellent prognosis for rapid recovery
• Axonotemesis :the axons (equivalents of the copper filaments in an electric cable) have been severed. The prognosis is moderate.
• Neurotemesis : this means the entire nerve has been divided. The prognosis is very poor.
• Neuroma : this refers to a type of tumor that grows from a tangle of divided axons (nerve endings), which fail to regenerate. The prognosis will depend on what percentage of axons do regenerate.

Brachial Plexus Injuries Risk factors

Participating in contact sports, particularly football and wrestling, or being involved in high-speed accidents increases your risk of brachial plexus injury.

Brachial Plexus Injuries Complications

Given enough time, many brachial plexus injuries in both children and adults heal with no lasting damage. But some injuries can cause temporary or permanent problems:

• Stiff joints. If you experience paralysis of your hand or arm, your joints can stiffen, making movement difficult, even if you regain use of your limb. For that reason, your doctor is likely to recommend ongoing physical therapy during your recovery.
• Pain. This results from nerve damage and may become chronic.
• Loss of feeling. If you lose feeling in your arm or hand, you run the risk of burning or injuring yourself without knowing it.
• Muscle atrophy. Slow-growing nerves can take several years to heal after injury. During that time, lack of use may cause the affected muscles to break down (degenerate).
• Permanent disability. How well you recover from a serious brachial plexus injury depends on a number of factors, including your age and the type, location and severity of the injury. Even with surgery, some people experience permanent disability, ranging from weakness in the hand, shoulder or arm to paralysis.