Transcription:
Reconstruction for Brachial Plexus Injury

Melanie: Welcome to Better Edge, a Northwestern Medicine podcast for physicians. I'm Melanie Cole. And today, we're talking about reconstruction for brachial plexus injury. Joining me is Dr. Kevin Swong. He's an Assistant Professor of Neurosurgery at Northwestern Medicine. Dr. Swong, thank you so much for joining us today. For those in the audience who may not be familiar, explain a little bit about the brachial plexus and what they are.

Dr Kevin Swong: Absolutely. Thank you for having me. The brachial plexus is essentially a network of nerves from C5 to T1 that come out of the spine and the spinal cord and supply all of the sensation to the arm and all the motor function to the arm as well.

Melanie: So knowing that this is a network of nerves, as you just said, how would an injury to it affect sensation or movement in the body? Is it only the upper half? Does it affect the lower? Tell us a little bit about how these injuries present themselves.

Dr Kevin Swong: So, brachial plexus injuries in a multitrauma setting is relatively common. About 2% of patients with multisystem trauma will have some sort of brachial plexus injury. It typically presents with a flacid paralysis of the arm and the extent and severity kind of depends on the extent and severity of the injury itself.

Melanie: Well, you just mentioned a little bit about how these injuries happen. Expand on that for us more, Dr. Swong. What do you typically see?

Dr Kevin Swong: Well, it can really be from any high velocity trauma. So car accidents are very common, more so because car accidents are common source of injury. But it could also be from falls. It can occasionally be from sports-related injuries or things that are kind of more sharp in nature, so sharp lacerations or gunshot wounds and things like that.

Melanie: So Dr. Swong, formerly brachial plexus lesions injuries were treated conservatively. But currently, operative care is a highly specialized field really that's limited to relatively few tertiary care centers and a wide variety exists of how these injuries are treated. How has this very specialized field evolved? What have you seen change over the years?

Dr Kevin Swong: You know, I think absolutely correct. Historically, outcomes for brachial plexus injuries were considered very poor. And when we say historically, that comes from like World War II, essentially. And over the past several decades, especially with the introduction of the operating microscope, our abilities of surgeons to explore and repair the elements of the brachial plexus have really expanded.

I think if you looked at the history of it, most traditionally, people would just do what's called an exploration. So they would have a patient who had brachial plexus injury. And after a period of time, without significant spontaneous recovery, they would go to the operating room and explore the brachial plexus.

Now, part of the issue is if you look at the brachial plexus and its elements after an injury, what's called a neuroma can form, which is essentially a scar tissue around the nerves. And the neuroma itself can look relatively normal. So just by going on inspection, it was difficult to tell what part of the nerve is functioning and what part of it wasn't.

Dr. Kline at LSU really pioneered the use of intraoperative monitoring. And so what he was able to do was find elements of the brachial plexus with the aid of intra-operative monitoring and test specific elements of the plexus. And by testing, which elements of the plexus were functioning versus non-functioning, really tailor the surgery and improve functional outcomes.

The mainstay of treatment was neuroma excision where we would cut out the non-functioning neural tissue and then replace it with donor nerve grafts, most likely from sensory nerves in other places in the body. And that's been the mainstay for treatment of brachial plexus injuries.

What has become kind of more prevalent is what's called nerve transfers. So the issue with nerve grafts or that when you cut out a neuroma, any functioning tissue that's still going through that neuroma is essentially removed with that non-functioning tissue. And nerve graft allows that functioning tissue to still continue to work, but supplies a functioning nerve from another part of the body. And so in essence, we're robbing Peter to pay Paul because we're taking nerves from a functional part of the body and rerouting them to a part of the body that doesn't work.

And that has several advantages. One is since the nerve is itself working. The time to recovery should be shorter because it doesn't have to grow through as much tissue in order to start the regeneration process. When you cut a neuroma, you have two sites of a cut, right? So there are two sites of what we call coaptation when we put the nerves back together. And each side of coaptation has a potential site of neuroma formation, which would inhibit regeneration. And so by doing a transfer, you cut them in half. So that's another potential benefit. But the downside is that not every nerve site is amenable to a nerve transfer just because of anatomic limitations. So when we look at these patients, what we try to do is tailor our reconstructive strategies through both of these methods and see which one would be most appropriate.

Melanie: Wow. So interesting. And thank you for telling us about the reconstruction process. And it is amazing how advances in radiologic imaging have really augmented your diagnostic and therapeutic capabilities. So as you're telling us about this, Dr. Swong, and given the complexity you just described and with increasingly complex treatment algorithms, speak about the multidisciplinary approach that is so important for these patients.

Dr Kevin Swong: Yeah, I'm really glad you brought that up because certainly especially for something like this, we cannot operate in a vacuum and we operate very closely with our physiatrists who are physicians who specialize in rehabilitation medicine, radiologists who specialize in imaging techniques, physical therapists and occupational therapists who help with range of motion and to prevent contractures.

And then within the surgical specialty ourself, it's more than just neurosurgeons. So the specialties that, I guess, participate in peripheral nerve surgery, are the neurosurgeons, plastic surgeon and orthopedic surgeons, each one brings the slightly different element and skill. And it is important to have as many people as possible because there are some things that are better fixed with no surgery. There are some problems that might be better fixed with like tendon transfers. And then, you know, obviously, if there are any broken bones or things like that, then orthopedic colleagues help with that as well. So it really does take a team approach.

And to that point, we are in the process of building and developing a brachial plexus center at Northwestern. It's very much in the early stages, but so far it would be myself, Dr. Jason Ko, who's a plastic surgeon, who also specializes in peripheral nerve surgery, and then physiatry and radiology as well.

Melanie: Wow. So based on what we've learned today, I can only imagine it must be an incredible intricate process when working on the brachial plexus. Is there anything you'd like to let other providers know about cutting edge technologies at Northwestern Medicine that your team is utilizing? Anything on the horizon or even any clinical trials or research that your team is working on that you'd like to let other providers know about?

Dr Kevin Swong: So nerve regeneration therapies are an active area of research at Northwestern. And we're investigating ways to try to augment nerve repair and nerve growth, specifically for nerve transfers. There's medications being investigated as well as therapies with electrostimulation. So that's a very active area of research.

The one that I'm interested in as well is radiology. So, when we look at MRI scans more often to evaluate the brachial plexus, there's no way to see if the neuroma or the scar tissue is contiguous or not. And we're developing techniques to try to get a better picture of the brachial plexus elements before surgery. So those are the areas we're looking at too.

Melanie: Fascinating field you're in, Dr. Swong. Is there anything else that you'd like to add? Any take home message? And certainly, I'd like you to mention when you feel it's important that other providers refer.

Dr Kevin Swong: The traditional teaching from medical school is that brachial plexus injuries don't have a great chance for recovery. And I think over the past 20 or 30 years, and certainly within the past 10 years, that thought process is really changing. And the uses for transfers or peripheral nerve surgery are always expanding. And so besides brachial plexus injuries, what they're looking at now is spinal cord injury to try to reanimate parts of the limbs that might've lost function or strokes.

What I would say to other providers is the outcomes are good and can restore a lot of function to patients and the sooner that we're able to see these patients, the better. So if we're going to intervene surgically, the ideal timeline is somewhere between six and eight months. And then after a year or so, outcomes become less good, but recovery is still possible even that far out.

Melanie: So the earlier, the better, yes?

Dr Kevin Swong: Absolutely.

Melanie: Thank you so much, Dr. Swong, for joining us. And I hope you'll come on and join us again and give us some updates as these technologies continue to evolve. To refer your patient or for more information, please visit our website at nm.org to get connected with one of our providers.

That concludes this episode of Better Edge, a Northwestern Medicine podcast for physicians. Please also remember to download, subscribe, rate, and review this podcast and all the other Northwestern Medicine podcasts. I'm Melanie Cole.