Most commonly result from motor vehicle accidents, gunshot or stab wounds, contact sport accidents, or workplace accidents during heavy physical labour.
May involve the upper 2 or 3 nerve roots (partial injury) or all 5 nerve roots (complete injury). Partial and complete brachial plexus injuries can both be repaired successfully, but complete injuries require multiple major operations over the course of several years, while partial injuries can often be corrected in a single operation.
Complete injuries can be ruptures (roots still connected to the spinal cord) or avulsions (roots detached from the spinal cord). Although ruptures have traditionally been treated with direct nerve repair and grafting, recent approaches have tended to use nerve transfer techniques, which can be successfully applied to both ruptures and avulsions.
An injury that does not resolve within a few days will often require major surgical reconstruction. The speed of nerve regeneration after spontaneous recovery or nerve repair is about 1 mm per day (1 inch per month).
Given the time frame to permanent paralysis (about 1 year), surgical repair is best carried out by 4 to 6 months after injury.
Brachial plexus injuries are usually caused by trauma to the roots of the plexus as they exit the cervical spine.[1]Nath RK, Lyons AB, Bietz G. Physiological and clinical advantages of median nerve fascicle transfer to the musculocutaneous nerve following brachial plexus root avulsion injury. J Neurosurg. 2006;105:1-5.
http://www.ncbi.nlm.nih.gov/pubmed/17405252?tool=bestpractice.com
This most commonly occurs in road traffic accidents and falls from height. Inflammatory, neoplastic, and compressive causes are also possible.[2]Moghekar AR, Moghekar AR, Karli N, et al. Brachial plexopathies: etiology, frequency, and electrodiagnostic localization. J Clin Neuromuscul Dis. 2007;9:243-247.
http://www.ncbi.nlm.nih.gov/pubmed/17989587?tool=bestpractice.com
The effects of the injury include paralysis, loss of sensation, and pain. The specific clinical presentation will depend on the roots involved and the degree of injury to each root.
[Figure caption and citation for the preceding image starts]: Left brachial plexusFrom the collection of the Texas Nerve and Paralysis Institute, Dr Rahul Nath, Founder and Medical Director; used with permission [Citation ends].