Brachial plexus injury

A brachial plexus injury is an injury to 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 or, in the most serious cases, torn. This usually happens when your shoulder is pressed down forcefully while your head is pushed up and away from that shoulder.

Brachial plexus injuries are common in contact sports, but they can also result from auto accidents, falls, inflammation and tumors. Babies sometimes sustain a brachial plexus injury during birth.

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


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. 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 even longer.

More-severe injuries
More-severe symptoms result from injuries that 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:

* The ability to use your fingers, but little to no control of your shoulder and elbow muscles
* The ability to use your arm but not your fingers
* Complete lack of movement and feeling in your arm
* Severe pain

When to see a doctor
Brachial plexus injuries can cause permanent weakness or disability. Don't take them for granted, even if they seem minor. See your doctor if you have recurrent burners and stingers, weakness in your hand or arm that lasts more than a few days, neck pain, or symptoms in both arms.


Causes

The nerves that make up the brachial plexus exit your spinal cord near the point where your neck joins your shoulder. They pass behind your collarbone (clavicle), dividing and recombining as they travel down your arms until they reach the tips of your fingers. The nerves that emerge higher in your neck serve your shoulder and elbow, and nerves that emerge lower in your neck serve your forearm and hand.

Damage to the upper nerves tends to occur when your shoulder is forced down, and your neck stretches up and away from the injured shoulder. The lower nerves are more likely to be injured when your arm is forced above your head. These injuries can occur in several ways:

* Contact sports. Many football players experience burners or stingers, which can occur when the nerves in the brachial plexus get stretched beyond their limit during collisions with other players.
* Difficult births. Newborns can sustain brachial plexus injuries when there are problems during birth, such as a breech presentation or prolonged labor. If an infant's shoulders get wedged within the birth canal, the force used to pull the baby free also can damage the nerves in the brachial plexus. Most often, the upper nerves are injured, a condition called Erb's palsy. Total brachial plexus birth palsy occurs when both the upper and lower nerves are damaged.
* Trauma. Vehicular accidents, especially motorcycle accidents, and boating accidents can result in brachial plexus injuries. Animal bites and bullet or knife wounds also can damage the brachial plexus.


Risk factors

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


Complications

Given enough time, many brachial plexus injuries in both children in 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 regenerate. During that time, lack of use may cause the affected muscles to 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.

Preparing for your appointment

A number of tests may be used to help diagnose the type and severity of brachial plexus injuries. When you make your appointment, be sure to ask whether you need to prepare for these tests. For instance, you may need to stop taking certain medications for a few days or avoid using lotions the day of the test.

Other suggestions for getting the most from your appointment include:

* Write down all your symptoms. Include how you were injured, how long you've had your symptoms and whether they've gotten worse over time.
* Make a list of all medications, vitamins and herbs that you're taking.
* If possible, take along a family member or friend. It can be difficult to absorb all the information you're given during an appointment. The person who accompanies you may remember something that you forgot or missed. This is especially important if your child has a brachial plexus injury. In most babies, the injury heals on its own without any lasting damage, but children who don't show improvement in the first six months of life may require surgery. This means parents that parents face some difficult decisions, and it's often helpful to have a friend or family member who can offer advice and support.
* Don't be afraid to ask questions. Children and adults with brachial plexus injuries have several options for restoring lost function. Be sure to ask your doctor about all the possibilities available to you or your child. If you run out of time, ask to speak with a nurse or have your doctor call you later.


Tests and diagnosis

To help diagnose the extent and severity of a brachial plexus injury, you may have one or more of the following tests:

* Electromyography. This test checks the health of the nerves that help move your muscles. After small needle electrodes are inserted through your skin into a muscle, you're asked to contract that muscle. The amount of electrical activity generated provides information about how well the muscle responds when its nerves are stimulated. You may feel a little pain when the electrodes are inserted, but most people can complete the test without much discomfort.
* Nerve conduction studies. These measure how quickly impulses are conducted through a nerve. Your nerve is stimulated through a patch-like electrode attached to your skin. This stimulation can feel like an electric shock of varying intensity. Although this test can be uncomfortable, you won't have any lingering pain afterward.
* Magnetic resonance imaging (MRI). An MRI uses radio waves and a powerful magnetic field to visualize structures in your body. It often can show the extent of the damage caused by a brachial plexus injury. This test is typically used to determine if a nerve has been severed completely from your spinal cord.
* Computerized tomography (CT) myelography. A myelogram is a type of X-ray that uses a contrast material, injected during a spinal tap, to produce a detailed picture of your spinal cord and nerve roots. In CT myelography, the images are taken with a CT scanner, a device that uses X-rays to create cross sections of body tissues. This test is sometimes performed when MRIs don't provide adequate information. Your doctor may tell you to drink more water the day before the test, and you may need to stop taking certain medications for a few days before a myelogram. Side effects of the test can include headache and nausea.


nTreatments and drugs

Nerves that have only been stretched have a fair chance of recovering on their own. But the healing process sometimes forms scar tissue that must be removed surgically to improve the nerve's function. Surgical repair is often required for nerves that have significant surrounding scar tissue or that have been cut or torn.

Types of surgery
In many cases, surgeons can take less important nerves from other parts of your body to help restore your arm's function:

* Nerve graft. In this procedure, the damaged part of the brachial plexus is removed and replaced with sections of nerves cut from other parts of your body — rather like splicing a bit of new electrical wiring in between two sections of old electrical wiring.
* Nerve transfer. When the nerve root has been torn from the spinal cord, surgeons often take a less important nerve that's still attached to the spinal cord and hook it into the nerve that's no longer attached. In some cases, surgeons may perform this technique at a level close to the targeted muscle in an effort to speed up recovery rather than doing a repair (nerve graft) farther from the muscle. Nerve tissue grows slowly, about an inch a month, so it can take several years to fully recover after surgery. During the recovery period, you must keep your joints flexible with a program of exercises. Splints may be used to keep your hand from curling inward.

Partly because of the risk of muscle atrophy, surgery to repair brachial plexus nerves should ideally occur within three to six months after the injury. The success rate drops greatly if nerve surgery occurs more than a year after the injury. If your muscles deteriorate, your surgeon may remove a less important muscle or tendon from another part of your body and transfer it to your arm.

Pain control
Pain from the most severe types of brachial plexus injuries has been described as a crushing sensation or a constant burning. Drugs containing opiates, such as codeine, are typically used immediately after the injury. Antidepressant and anticonvulsant medications also can be helpful, and a procedure called transcutaneous electrical nerve stimulation (TENS) sometimes provides relief. TENS involves using electrodes attached to your skin to deliver electrical impulses to nearby nerve pathways to help control and relieve pain. In extreme cases, surgery may be necessary.


Prevention

Although damage to your brachial plexus often can't be prevented, you can take steps to reduce the risk of complications once an injury has occurred:

* For yourself. If you temporarily lose the use of your hand or arm, daily range-of-motion exercises and physical therapy can help prevent joint stiffness.
* For your child. If you're the parent of a child with Erb's palsy, it's vitally important that you exercise your child's joints and functioning muscles every day, beginning when your baby is about 3 weeks old. This helps prevent the joints from becoming permanently stiff and keeps your child's working muscles strong and healthy.