Brachial Plexus Injury - A Pain In The Neck?

Brachial Plexus injuries present unique challenges, this complex neurological condition can significantly impact an athlete's performance. In this blog I hope to give the reader some insight into what the brachial plexus is, how this impacts on function/sports performance and some discussion around the management of such an injury.

Anatomy and Function of the Brachial Plexus:

The brachial plexus is a network of nerves that originate from the cervical and thoracic spinal cord segments, forming an intricate web that supplies motor and sensory innervation to the upper extremities. Comprising roots, trunks, divisions, cords, and branches, the brachial plexus is a robust structure essential for precise movement and sensation, however it is susceptible to injury from contact sports, gunshot or stab wounds .

Joints and Relevant Anatomy:

Shoulder Joint:

• Brachial plexus innervates shoulder muscles (e.g., deltoids, rotator cuff).
• Nerve compromise can lead to weakness, instability, and altered biomechanics.

Elbow Joint:

• Brachial plexus controls muscles for elbow flexion and extension.
• Athletes relying on powerful arm movements (e.g., tennis players, weightlifters) may be significantly impacted.

Hand Joints:

• Brachial plexus vital for hand function, impacting fine motor skills.
• Athletes may experience compromised grip strength, precision, and coordination with brachial plexus injuries.

Grades of Brachial Plexus Injuries:

Brachial plexus injuries are commonly classified into different grades based on the severity of nerve damage. This classification system helps guide clinicians in developing appropriate management strategies:

Neurapraxia (Grade I): Mild injury involving temporary conduction block without structural damage. Athletes may experience temporary weakness but typically recover fully.

Axonotmesis (Grade II): Moderate injury involving nerve fibre damage. Recovery is possible, but it may take weeks to months, and some residual deficits may persist.

Neurotmesis (Grade III): Severe injury involving complete nerve transection. Surgical intervention may be required for optimal recovery, and the prognosis is often guarded.

Mechanisms of Injury:

Athletes are exposed to various mechanisms that can lead to brachial plexus injuries, and understanding these mechanisms is crucial for prevention and early intervention:

Direct Trauma: High-impact collisions or falls can directly compress or stretch the brachial plexus, leading to injury. For example, in rugby a common neuropraxia injury called a “stinger” happens when a tackling player compresses and stretches the plexus causing a stinging sensation with pins & needles and momentary loss of function.

Overuse and Repetitive Stress: Athletes engaging in repetitive, forceful arm movements, such as throwing or swinging, may be susceptible to overuse injuries affecting the brachial plexus. 

Management Strategies:

Effective management of brachial plexus injuries in elite athletes requires a multidisciplinary approach, integrating the expertise of physiotherapists, sports medicine physicians, and, in severe cases, surgeons. 

Early Rehabilitation Programs: Tailored rehabilitation programs focusing on neural mobilisation, strengthening exercises, and proprioceptive training to optimise functional recovery should be started as soon as practical. Stimulating the nerve will help to facilitate recovery.

Functional Electrical Stimulation (FES): Implement FES to facilitate muscle contraction and prevent disuse atrophy, particularly in cases where direct nerve damage is present. This can be achieved under supervision either with a physiotherapist or a specialist neurological rehabilitation unit depending on the severity of FES necessary, 

Surgical Intervention: In severe cases, surgical exploration and repair may be necessary to restore nerve continuity and function. Recent advancements in microsurgical techniques have improved outcomes but a surgical consultation should be sought if the injury has not spontaneously resolved in a few days or weeks.

Conclusion:

Brachial plexus injuries pose a significant challenge for recovery, a comprehensive understanding of the anatomy, grading and mechanisms of injury, are important in regards to helping to devise appropriate management strategies. Significant injury that does not recover spontaneously within a few days, will often require surgical intervention in order to facilitate optimal recovery of function. Given the speed of nerve regeneration after spontaneous recovery or nerve repair is about, 1 mm per day (1 inch per month), the time frame to permanent paralysis (about 1 year), surgical repair is best carried out by 4 to 6 months after injury, should be followed by a rigorous attempt at conservative management.

References:

Best Practice BMJ. (2023, October 26). Topic title. https://bestpractice.bmj.com/topics/en-gb/581: https://bestpractice.bmj.com/topics/en-gb/581

Moghekar AR, Moghekar AR, Karli N, et al. Brachial plexopathies: etiology, frequency, and electrodiagnostic localization. J Clin Neuromuscul Dis. 2007;9:243-7.

Troyer, W., Gardner, J. E., & Bowers, R. L. (2023). Neurogenic thoracic outlet syndrome in the overhead and throwing athlete: A narrative review. PM&R, 15(5), 629-639. doi:10.1002/pmrj.12816