MUSC Neurosurgeons Specialize in Complex Brachial Plexus & Peripheral Nerve Repairs

The brachial plexus – a complex network of nerves that emerge from the upper spine and neck – travels across the back, shoulders, and chest, and down into each arm. Damage to any part of this neural network can have devastating effects, including: severe, chronic pain; loss of shoulder, arm, or hand function; disability; and poor quality of life.¹ However, conditions affecting the brachial plexus can be difficult to diagnose, because this complicated, three-dimensional structure is challenging to image, and deficient nerve conduction and the resulting muscle weakness can take weeks or months to appear.2

Abhay Varma, M.D., is a Professor of Neurosurgery at the Medical University of South Carolina (MUSC). “We group brachial plexus and peripheral nerve conditions that can be surgically addressed into three broad categories: traumatic injuries including stretch injuries, nerve tumors, and nerve entrapments,” says Varma.

Brachial and peripheral nerve injuries are most commonly caused by motor vehicle accidents with trauma to the upper body or “whip-lash” forces that overstretch the nerve fibers.³ Motor-cycle accidents account for the majority (67%) of peripheral nerve injuries needing surgical repair, and car crashes account for about 14%.⁴ “High-speed collisions pull your head away from your shoulders, causing a stretch injury in the brachial plexus and peripheral nerves,” says Varma.

“We also see stretch injuries in newborns called, neonatal brachial plexopathy, which occurs when the shoulder gets stuck in the birth canal under the pelvic bone,” says Varma. “Surgery can be necessary in some of these cases to ensure a functional upper extremity, so the child has use of both arms if possible.” Varma’s team is the only group in South Carolina that performs this procedure. “We get referrals from all over the state for this type of neonatal surgery.”

Despite the risk of permanent disability, delays in treating brachial plexus and peripheral nerve conditions are common and often allow nerve damage to progress, reducing the chance of complete functional recovery.⁵ One reason for delayed diagnosis is that it is very challenging to assess the location and extent of nerve damage in patients with multiple traumatic injuries. In addition, symptoms of nerve damage may not be immediately evident to either the patient or treating physicians. Finally, because nerves can sometimes regenerate and regain function on their own without surgical intervention, some physicians prefer to postpone the decision to pursue surgical repair.⁶

Tumors can also cause dysfunction in the brachial plexus and peripheral nerves and often must be surgically removed to preserve function in the affected limb or organs. “Most often, the patient notices a lump in their upper extremity or above their collarbone in the supra-clavicular region,” says Varma. “Tumors affecting deep-seated nerves can’t be felt by hand but cause new onset numbness, tingling, weakness, or pain from the tumor stretching or compressing the nerve.”

A critical factor behind the high neurosurgical success rates at MUSC is the availability of advanced imaging technology. “We start every case with really good preoperative imaging to visualize the tumor and its relationship to surrounding structures. Tumors tend to run with blood vessels and other important nerves, so we need to know as much about it as we can prior to surgery,” says Varma. “We also need to carefully identify the normal nerve which is often draped and stretched around the tumor. It’s critical to isolate and protect the functional nerves and be sure not to cut or pull them.”

The MUSC neurosurgical team also uses the latest intra-operative monitoring techniques to note any functional changes during the procedure and facilitate real-time decision-making. If individual nerve fibers are difficult to distinguish from the tumor, the team uses triggered electromyography (tEMG) to stimulate the nerve root. “The tEMG tells us if there is viable neural tissue in the area so we can be careful,” says Varma. “We also look at continuous conduction through evoked potentials throughout surgery. We get a baseline beforehand and keep testing during the procedure to monitor for any drop in those potentials.”

Microscopic and advanced nerve grafting techniques also improve patient outcomes after brachial plexus or peripheral nerve repair. “This is most helpful when the two ends of the divided nerve cannot be approximated without tension. Use of nerve grafts harvested from patient’s own nerves (autografts) or nerve grafts harvested from organ donors (allografts), can be used to bridge the gap between two ends of the injured nerve,” says Varma. “It takes time, but we can usually restore function with a graft,” says Varma. “With autologous grafts from the patient, we’re limited to which nerves we can take, because we can’t cause a new deficit. For major nerve injuries, we may have to place multiple grafts to match the diameter. Allografts from a cadaver give the surgeon more choice in terms of length and diameter.”

“A technique called neurotization is one of biggest recent advances,” says Varma. “We take part of a healthy nerve and connect it to the injured nerve at a site distant from the injury site. Basically, we bypass the injury. It has really good results, especially in children.” The team also does emergency surgery for acute, clean-cut injuries. “We can actually stitch the two ends of the nerve back together,” says Varma. “If we get it back together fast enough, it will heal itself. When too much time has passed for that, you can graft it and restore function even if the nerve is completely divided in two.”

With advanced technologies at their disposal and many years of experience, MUSC neurosurgeons specialize in diagnosing and repairing rare and difficult-to-treat brachial plexus and peripheral nerve conditions. “We have good success with very challenging patients such as those with neurofibromatosis and those with very large tumors involving critical nerves of body like the sciatic nerve,” says Varma.   

To refer a patient, schedule a consult, or make an appointment with MUSC Health Neuroscience Services, please call 843-792-7700.

References

1 Simon NG, Spinner RJ, Kline DG, Kliot M. Advances in the neurological and neurosurgical management of peripheral nerve trauma. J Neurol Neurosurg Psychiatry. 2016;87(2):198-208. doi:10.1136/jnnp-2014-310175

2 Simon NG, Spinner RJ, Kline DG, Kliot M. Advances in the neurological and neurosurgical management of peripheral nerve trauma. J Neurol Neurosurg Psychiatry. 2016;87(2):198-208. doi:10.1136/jnnp-2014-310175

3 Martin, E., Senders, J. T., DiRisio, A. C., Smith, T. R., & Broekman, M. L. D. (2019). Timing of surgery in traumatic brachial plexus injury: a systematic review, Journal of Neurosurgery JNS, 130(4), 1333-1345. Retrieved Mar 28, 2022, from https://thejns.org/view/journals/j-neurosurg/130/4/article-p1333.xml

4 Kaiser R, Waldauf P, Ullas G, Krajcová A. Epidemiology, etiology, and types of severe adult brachial plexus injuries requiring surgical repair: systematic review and meta-analysis. Neurosurg Rev. 2020;43(2):443-452. doi:10.1007/s10143-018-1009-2

5 Martin, E., Senders, J. T., DiRisio, A. C., Smith, T. R., & Broekman, M. L. D. (2019). Timing of surgery in traumatic brachial plexus injury: a systematic review, Journal of Neurosurgery JNS, 130(4), 1333-1345. Retrieved Mar 28, 2022, from https://thejns.org/view/journals/j-neurosurg/130/4/article-p1333.xml

6 Martin, E., Senders, J. T., DiRisio, A. C., Smith, T. R., & Broekman, M. L. D. (2019). Timing of surgery in traumatic brachial plexus injury: a systematic review, Journal of Neurosurgery JNS, 130(4), 1333-1345. Retrieved Mar 28, 2022, from https://thejns.org/view/journals/j-neurosurg/130/4/article-p1333.xml