What is a Brachial Plexus Injury?

The brachial plexus (BRAY-key-el PLEK-sis) is a network of nerves that provides movement and feeling to the shoulder, arm, and hand. The nerves supporting the arms exit the spinal column high in the neck; those that support the hand and fingers exit lower in the neck.

This nerve complex is composed of four cervical nerve roots (C5-C8) and the first thoracic nerve root (T1). These roots combine to form three trunks. C5-C6 form the upper trunk, C7 continues as the middle trunk and C8-T1 form the lower trunk.

Each trunk splits into a division. Half the divisions globally supply flexor muscles (that lift and bend the arm). The others supply the extensor muscles (that straighten the arm and bring it down).

Causes of Brachial Plexus Injury

Most traumatic brachial plexus injuries occur when the arm is forcefully pulled or stretched. Many events can cause injury, including falls, motor vehicle collisions, knife and gunshot wounds, and even as a result of birth trauma.

It is not known exactly how many brachial plexus injuries occur each year, but the number seems to be growing throughout the world. Increased participation in high-energy sports and higher rates of survival from high-speed motor vehicle collisions may be factored in the growing number of these injuries.

Many brachial plexus injuries occur when the arm is pulled downward and the head is pushed to the opposite side.

Symptoms of Brachial Plexus Injury

Symptoms vary depending upon the type and location of the injury to the brachial plexus as well as whether the patient sustained other injuries. The most common symptoms of brachial plexus injury include:

  • Weakness or numbness
  • Loss of sensation
  • Loss of movement (paralysis)
  • Pain

The pain from brachial plexus injuries results from injury to the spinal cord where the nerve rootlets are avulsed from the cord. This pain is neuropathic in nature and can be very difficult to deal with. The pain can last for a very long time.

Brachial plexus injuries that occur at the level of the spinal cord often produce greater pain than injuries more distant from the spinal cord. In addition, injuries nearer the spinal cord may cause a burning numbness, which is called paresthesias or dysesthesias.

Treatment of Brachial Plexus Injury

Brachial plexus is a complex network of nerves, formed in the posterior cervical triangle by the union of ventral rami of fifth, sixth, seventh, and eighth cervical nerve roots and first thoracic nerve root and is responsible for the innervation of the upper extremity.

The type of brachial plexus injury (BPI) is determined by the location of injury within the nerve route, that is, within the rootlets, the roots, or within the intervertebral foramina and the severity of the damage extending from a mild stretch to the nerve root tearing away from the spinal cord.

Traumatic BPIs may occur due to motor vehicle accidents, bike accidents, sports, etc., The prognosis is thus based on the size and type of BPI. For the treatment of BPI, there are few nonoperative (conservative) management strategies including rehabilitation and physiotherapy through which reasonable mobility can be achieved. 

However, stem cell therapy has shown great potential in treating brachial plexus injury. Stem cell therapy has the potential to repair the underlying nerve damage. The therapy has been postulated to have the potential to work at the microcellular level promoting reparative effects on the damaged nerve.

Cellular therapy is emerging as a therapeutic approach for neuromuscular injury. Stem cells possess the ability of self‑renewal and multi‑differentiation, in addition to having an immense safety profile.