The brachial plexus is a network of nerves which originate at the spinal cord and send signals to the shoulder, arm and hand to allow movement and function. The nerves supply the muscles to make them work and register sensation, so we can feel touch, temperature and pain.
The brachial plexus is made up of 5 nerves that originate at the spinal cord which then branch off, mix together, and divide into smaller nerves (including the musculocutaneous nerve, axillary nerve, radial nerve, median nerve and ulnar nerve). Each of these nerves has a specific area of skin and a particular set of movements to control.
What are nerves?
Nerves are cord-like structures which contain many nerve fibres that send signals from the brain to the muscles (motor function) and sensory signals from the periphery (skin and joints) to the brain (sensory function).
For a muscle to work (contract) the signal must first come from the brain, if the nerve has been injured along this route the signal may be interrupted and the muscle may not work or may be weakened. For sensation to work, there must be an intact nerve from the skin back up to the brain.
How do brachial plexus injuries occur?
Brachial plexus injuries are usually high velocity trauma injuries, such as road traffic accidents, high energy falls, traction injuries or penetrating wound injuries.
- Wounds that cut the nerve
- Severe stretching of the nerve
- Compression of the nerve
Sometimes they occur for other reasons, such as shoulder dislocations, or because of pressure from nearby structures or growths.
Types of nerve injury
Stretch or compression of the nerve with no structural damage. Nerve usually recovers quickly, 2 to 12 weeks.
Some parts of the nerve are intact, but some axons are damaged and slowly regrow at a maximum of 1 to 2mm a day. The nerve may recover to some degree but may take several months.
The nerve is cut or stretched to breaking point (complete rupture), these will not heal without surgery.
- Nerve root avulsion
Nerves are pulled away at the level of the spinal cord, the nerve cannot be re-joined at this level, and surgery may involve nerves being transferred from other areas to improve function – this is the most severe type of nerve injury.
How to determine the severity of the brachial plexus injury
The severity of the injury will vary from patient to patient, as no two injuries are the same. Some investigations may be completed to confirm findings after a physical assessment, such as:
- Nerve conduction studies and EMG (electromyography)
- MRI scans
- Exploratory operation (your consultant will determine if this is deemed necessary and this is usually combined with surgery to treat the injury where possible)
Recovery of the damaged nerves
It can take several years for the nerve to recover and sometimes a nerve is so severely damaged it never fully recovers.
Even those nerves that recover well from surgery never fully return to their pre injury state.
Initially, following your injury, you will be assessed by members of the MDT
(Multidisciplinary Team). The members of our team are your consultants (Plastic Surgery, Orthopaedic Surgery and sometimes both), one or more experienced physiotherapists and sometimes an occupational therapist or neurophysiologist.
It is important that following your injury, stiffness is prevented in the joints, as you may be unable to move your arm or hand on its own. You will need guidance from the team as to which are the most appropriate exercises for you to do, to maintain range of movement in your shoulder, elbow, wrist and hand. Some form of splint or brace may also be necessary to help maintain joint positions.
Pain can come from a variety of sources, but nerves can also produce pain known as neuropathic pain. This can vary from mild pins and needles to severe electric shocks and can include burning or pressure sensations. Pain medication plays an important part in your rehabilitation and your GP and hospital team will be able to advise you.
Where pain control is proving difficult through standard measures, your team may refer you to our specialist pain management service.
The level and severity of the injury, and the time passed, will determine if surgery is likely to be beneficial to your recovery. Surgery may include:
- Decompression: relieving pressure on a nerve to help it recover
- Neurolysis: releasing of scarring around the nerve to improve recovery
- Nerve grafting: a section of the injured nerve is replaced, or a gap in a divided nerve bridged using a section of healthy “spare” nerve taken from another area of the body. The fibres still have to regrow, slowly at 1 to 2mm per day, with the nerve graft acting as a bridge for the nerve fibres to grow across.
- Nerve transfer: nerves can sometimes be routed from other nearby areas of the body to help improve the function of the injured arm or hand; these nerves will have to be retrained to do their new job.
- Tendon transfer: muscles start and finish with a tendon which attaches to a bone. When a nerve injury means that a muscle may not recover, a tendon transfer can be used to detach a muscle that is still working and move it to a different place to take over a missing movement.
Following surgery, it would be usual that your arm will be immobilised in a sling to protect any repairs.
Specific instructions will be given at the time of surgery about how long to rest you arm, and any exercises that may be recommeded for you.
A brachial plexus injury can be life changing and can impact on lots of different aspects of daily life. There may be changes to your appearance , employment status may change and your ability to do activities of daily living independently. You may be relying on other people to assist you and find changes to social situations challenging, such as eating out in restaurants.
It is expected that a range of emotions may be experienced throughout your rehabilitation process.
People often benefit in accessing psychological support such as counselling, talking therapies or mindfulness activities.
We have a Clinical Psychology team, and their support would usually be offered to you, or you may request this at any point as part of your on-going rehabilitation.
South Tees Hospitals NHS Foundation Trust would like your feedback. If you wish to share your experience about your care and treatment or on behalf of a patient, please contact The Patient Experience Department who will advise you on how best to do this.
This service is based at The James Cook University Hospital but also covers the Friarage Hospital in Northallerton, our community hospitals and community health services.