Brachial plexopathy is any injury to the brachial plexus—the nerve bundles located on each side of the neck that give rise to the individual nerves controlling the muscles of the shoulders, arms, and hands.
Brachial plexopathy occurs most often during birth, when an infant's neck and shoulders are stretched apart
during passage through the birth canal. Injury to the brachial plexus is referred to by various names. Some names, such as obstetric Erb's palsy, refer to the specific region of the brachial plexus where the injury has occurred. Other more general names for the condition include:
obstetric brachial plexus
brachial plexus injury (BPI)
brachial plexus palsy (BPP)
brachial palsy in the neonate
Brachial plexus injuries
The nerves of the brachial plexus are the fifth through the eighth cervical nerves (C5, C6, C7, and C8) and the first thoracic nerve (T1). They run from nerve roots on each side of the upper spinal cord to regions beneath the collarbone where they branch out as the major nerves of the shoulders, arms, wrists, and hands.
Every brachial plexus injury is different, depending on the affected nerve or nerves and the extent and severity of the injury. There are four general types of injury, and an individual brachial plexopathy may include any or all of these injury types, on one or both (bilateral) sides of the body. The types are as follows:
A stretch, praxis (damage), or traction (pulling or tension-creating) injury, in which the nerve has been overstretched and damaged but is not torn. Most brachial plexus injuries in newborns are of this type.
A rupture, in which there has been a separation within a nerve. A single nerve may have more than one rupture.
A neuroma, in which scar tissue has formed around a nerve injury. The scar tissue puts pressure on the nerve and interferes with nerve signal conduction to the muscles.
An avulsion is the most severe form of brachial plexus injury. It is the detachment of a nerve from the spinal cord.
A minor brachial plexus injury can be a stretched nerve that results in a short-circuit in a few of the nerve fibers, causing temporary paralysis. A more severe injury may involve a complete disruption of the nerve, in which the nerve fibers around the injury become disorganized, all nerve function is lost, and scarring prevents the nerve from healing. Such an injury can result in permanent paralysis.
Margaret Alic Ph.D., Thomson Gale, Gale, Detroit,