Brachial plexus injuries are typically caused by traction of the arm at birth and by road traffic accidents. They result in loss of sensation and movement in all or part of the arm and can be associated with severe pain. The exact symptoms depend on the severity and location of the injury.
Brachial plexus injuries in which the nerves are injured but still intact are usually managed by conservative care, including physiotherapy. If the plexus has been disrupted, then surgical repair is considered. This may be possible by direct suture, or it may involve the use of nerve grafts if the nerve ends are separated. If neither of these is possible, for example in nerve root avulsion, nerve transfer (neurotisation) can be done, in which a healthy nerve to a different muscle is joined to a damaged nerve, to re-innervate the affected arm muscle. A variety of nerves may be used for this kind of procedure, including intercostal nerves, the spinal accessory nerve, the phrenic nerve and the motor branches of the cervical plexus. Sometimes, free muscle or tendon transfer is done in combination with nerve transfer to re-innervate the forearm muscles.