What is a brachial plexus injury?
A brachial plexus injury occurs when the ‘brachial plexus’ (which is a group of nerves that run from the neck to the arm) becomes damaged, which can result in a wide range of problems linked to pain, sensory loss or change and paralysis or inability to use the shoulder, elbow, forearm or hand. Brachial plexus injuries most commonly occur due to road traffic accidents but can also occur from injuries in contact sports, such as rugby and martial arts, and can also occur in children during birth and personal accidents. The brachial plexus can also be damaged from radiation, tumours and injuries from medical procedures such as positioning during surgery.
What is the brachial plexus?
The brachial plexus sends and receives signals from the brain and spinal cord to the upper limbs (the shoulders, arms and hands), It runs from the neck and across the upper torso into the armpit and down the arm. It forms the major nerve branches, extending along the arm:
- The dorsalscapular nerve, which controls the positioning of the shoulder blade.
- The suprascapular nerve, which controls the turning out of the shoulder
- The long thoracic nerve, which stops the shoulder blade from winging.
- The musculocutaneous nerve, which flexes muscles in the upper arm at the shoulder and elbow.
- The axillary nerve, which enables shoulder rotation and the arm to lift away from the body.
- The median nerve, which enables movement in the forearm and hand.
- The radial nerve, which controls movement in several muscles from the upper arm down to the hand.
- The ulnar nerve, which enables fine motor control in the fingers.
What are the symptoms of a brachial plexus injury?
Symptoms commonly associated with a brachial plexus injury are:
- Severe pain in the arm; in mild injuries, the pain can be short-lived and feel like burning or stinging (which is why they are sometimes referred to as ‘burners’ or ‘stingers’), but in more major injuries, the pain can be life-altering.
- Numbness and tingling, increased sensation or loss of sensation.
- Inability or difficulty to manoeuvre the shoulder, arm, wrist or hand, and in some cases, complete paralysis of the arm.
What are the types of brachial plexus injuries?
There are three main types of brachial plexus injury:
Stretching of the nerves (neuropraxia)
Brachial plexus neurapraxia occurs as either compression or traction. In this injury the nerves of the brachial plexus can be thought of as ‘bruised’ they are not pulled apart but are not working. A kind of concussion of the nerve. This is seen in lower energy injuries and can sometimes get better given time. In some cases surgery is needed to improve it. It should be assessed by an expert.
Degenerative traumatic nerve injury
The nerves are snapped or pulled apart, which can also, in some case affect the wrapper around the nerve or leave the whole nerve pulled apart. These injuries need assessment and often treatment by an expert in brachial plexus injury. Recovery can take many months and will never return to normal; early treatment must be sought to get the best recovery possible.
Displacement of the nerves from the spinal cord (avulsion)
A brachial plexus avulsion is the most severe type of brachial plexus injury that can lead to permanent damage. It is when the nerve root is completely pulled clean from the spinal cord, often due to trauma like car accidents. An avulsion is associated with extreme pain, and can be more difficult to treat, which means patients may face permanent weakness, numbness, or paralysis in the shoulder, arm, or hand.
What causes brachial plexus injuries?
Causes of brachial plexus injuries include:
- Blunt trauma
- Athletics
- Lacerations or open wounds, such as blades and gunshot wounds, that damage the nerves
- Medical trauma, where the nerves are damaged during surgical procedures
- A tumour grows that disrupts the placement of the nerves
- Radiation therapy, which damages the nerve tissues
A brachial plexus injury may occur at birth, called a birth brachial plexus injury. This can happen due to forces being applied to the baby’s head to overcome a blockage along the vaginal canal. This force may pull apart their head and their shoulders.
Some children can recover spontaneously or regain function over time with physical and occupational rehabilitation, whereas others may require surgery to repair damage. It is essential that, if the condition has not completely recovered by 6 weeks, an expert is consulted.
How are brachial plexus injuries diagnosed?
Brachial plexus injuries are diagnosed by experts after assessing all the aspects of the injury and examining the patient to look for the degree of damage. Sometimes imaging tools may be employed, including imaging scans like X-rays and MRIs to visualise the nerves and other soft tissues, or nerve conduction studies, which use electrodes to determine nerve function and electrical activity.
How are brachial plexus injuries treated?
In some cases, especially for neuropraxic injuries, patients may heal without any medical intervention, though it may take several months; certain exercises and stretches can aid in this. Nonsurgical treatment approaches utilise topical or injected steroids to promote healing, or medications for pain management. Patients may be recommended to use braces, splints, or compression sleeves to assist with healing and pain reduction. Conservative treatment like this may be conducted by orthopaedic specialists.
More severe injuries will require surgery. Some surgeries that can be used in this case include:
- Nerve repair
- Neurolysis, where scar tissue on the nerves is removed
- Nerve graft, where a healthy nerve from elsewhere in the body is used to bridge the two ends of a severed or torn nerve
- Nerve transfer, where a healthy nerve is permanently implanted where the damaged nerve is
- Tendon and muscle grafts, to assist with arm movement and function
- Surgical treatments for nerve pain include neurolysis, neurectomy, neuroma relocation, targeted muscle reinnervation (TMR), or regenerative peripheral nerve interface (RPNI).
Surgeons specialising in the nervous system, such as nerve surgeons or neurospinal surgeons, are best equipped to perform surgery to repair a brachial plexus injury.
