CARPAL TUNNEL SYNDROME EXPLAINED
Transcript:
Heather Benjamin: Thank you for joining us for our educational webinar, “Carpal Tunnel Syndrome.” Tonight’s speaker will be Dr. Gary Millard, an orthopedic hand surgeon at OrthoNeuro.
Dr. Millard is a board-certified, fellowship-trained orthopedic surgeon specializing in hand and upper extremity care and surgery. He attended the University of New England College of Osteopathic Medicine and completed his residency at Oklahoma State University at the Hillcrest Health Center in Oklahoma City, Oklahoma.
Dr. Millard is fellowship-trained in hand surgery and trauma. He has served as the consulting team physician for the Columbus Blue Jackets at Ohio University.
Dr. Gary Millard: So, as mentioned, I am Dr. Gary Mallard. I’m a board-certified orthopedic surgeon. I specialize in hand and upper extremity surgery. I’ve also completed a fellowship in trauma surgery. So I do a lot of upper extremity trauma.
What we are going to talk about tonight, however, is not trauma. It’s probably one of the most common issues that face hand surgeons during our practice today, and that is carpal tunnel surgery.
So, what are we going to talk about now that I figured that out is basically the definition of carpal tunnel: What it is. What patients do we find with carpal tunnel symptoms? What causes it? Some of the clinical features, the complaints patients arrive with, some of the diagnostics of it, and how we treat it.
So, carpal tunnel syndrome is the most common peripheral neuropathy. Carpal tunnel is a compression of the median nerve at the wrist.
So, when we look at the carpal tunnel, it’s actually an anatomic structure. It’s a very small, enclosed space. And what happens through the small area called the carpal tunnel is we have nine tendons passing through that. That is basically all the tendons that flex our fingers, as well as the median nerve. So it is a very confined space for a number of structures.
When the median nerve is compressed at the wrist, it results in numbness or pain in the wrist and going to the fingers. So, basically, carpal tunnel affects approximately 3% of all adult Americans. It is three times more common in women than men.
The highest prevalence rates have been reported in people who perform repetitive wrist motions, often with computer users. That’s probably the most common finding.
Of those people who present complaining of carpal tunnel-type symptoms, 30% of them complain of hand numbness, and tingling, 10% of people actually fit the clinical criteria for carpal tunnel, and of those, 3.5% actually have abnormal nerve conduction studies. So basically, only 10% of the people that complain of numbness in their hand actually have nerve studies that confirm carpal tunnel.
When it comes to carpal tunnel, there are a huge number of factors that can be included. I’ve just included this list so that everyone can see the huge number of possibilities that cause carpal tunnel.
Again, one of the most common questions that I get asked is, “What caused my carpal tunnel? Why did it happen to me? Why did it happen in my non-dominant hand as opposed to my dominant hand?” And this is just a short, abbreviated list of any possible causes of carpal tunnel.
So, when it comes to clinical features of carpal tunnel, people will often complain of pain, numbness, and tingling in the hands. Most patients complain of their symptoms are worse at night and awaken the patients frequently.
They often wake up at night complaining that they have to shake their arm or flick their wrist to try to get their hand feeling back to normal again. It feels like there’s no blood going to the hand.
A lot of times the pain and paraesthesias don’t just occur in the hand. A lot of patients complain of pain that feels like it goes all the way from the hand up to the elbow, up to their shoulder.
Another very common complaint is that patients complain of a loss of dexterity. That means that they have a harder time using their hands, picking stuff up, and feeling stuff. They feel like they tend to drop things a lot and they’re not even aware of dropping them.
I’ll show you a picture in a minute, but atrophy of your thenar muscles—that’s the muscles in the base of your thumb. Those can atrophy, and that’s usually a sign of severe carpal tunnel.
Again, patients often will have bilateral symptoms. Generally, one hand will be worse than the other. And a lot of times it does not coincide with the hand of dominance.
This is a picture of the thenar atrophy. If you look at the base of your thumb, you can see a fairly well-developed muscle area there. The small circle area shows you the sign of atrophy in those muscles. That is a sign of severe carpal tunnel.
There are a few things that we look for when we examine people. And I’ll show you a little bit about each one. First off, the Phalen’s maneuver. Basically, we flex the patient’s wrist all the way down to about as far as they can tolerate, or 90 degrees, and hold it there for about a minute to see if the patient’s symptoms are reproduced by this. This is, again, compressing the area in the carpal canal, putting a little more pressure on the nerve.
Tinel’s sign is usually the most uncomfortable for the patient. And what we do is, right over the carpal canal, we just tap right on the nerve and look to see if they get numbness going in the median nerve distribution that kind of reproduces their symptoms.
So, when we’re looking at diagnostics for carpal tunnel, the first thing we listen to is the patient’s history. We listen to their complaint, see when they’re having numbness, see where the numbness is and how much that bothers them and when it bothers them.
We also do a compression test where we just put pressure straight over the nerve and wait to see if that reproduces the symptoms. If these findings are positive or patients complain of a recurrence of their symptoms, usually the next thing we do is something called the nerve conduction study where basically, and I will admit it is not the most fun test to go through in the world, but basically you get little shocks in your fingers and electrodes record how fast the nerve conduction goes across your nerve.
That can actually help you determine and is what helps determine, basically, whether the carpal tunnel is mild, moderate, or severe. And it confirms our findings in diagnostic studies.
Once carpal tunnel is confirmed, we have a few treatments we look at, and we say somebody has carpal tunnel, how do we treat these patients? The first general measures we look at are some behavior modifications. We try to have patients avoid repetitive wrist and hand motions that may make their symptoms worse.
Try to avoid the use of vibratory tools. A lot of people that use drills or anything that vibrates on a consistent basis can really irritate the nerve. So we try to limit their motion.
And then we can try to change the way people work. If they work at a computer, we can try to give them a little pad to rest their wrists in a slightly different position, so they’re not putting as much pressure on the nerve. So we try to just limit how much stress they’re putting on the nerve and the rest area.
There are a number of things. Some things work, and some things don’t. If you’re looking at the screen, the picture on the left with this fancy-looking pen—that’s probably not something that’s going to help you that much.
If you look at the picture on the right, that is somebody’s mousepad on there with a small bump on their wrist. That just changes the angle of your wrist to make things a little more comfortable to take out the stress on the wrist.
When it comes to wrist splints, this is something we try on most patients. It’s generally the most effective when it’s used within the first three months of onset.
When it comes to the best regime for this or the best use of the splinting—the first thing I always encourage people is to use the splinting at night. That usually helps them sleep a little better. And again, if they’re working on the computer all day, using the splints when they’re on the computer does help take some pressure off the wrist itself.
These are just a couple of examples of some splints. The one on the left is obviously a lot more cumbersome, but that is something that usually works very well for people to sleep in. It’s a little harder for people to work in that.
And even the ones on the right are very small, but they can help just by adjusting the angle of your wrist when you’re working on a computer.
There have been a lot of studies on carpal tunnel about different medications people can take to try to help the carpal tunnel. People have used diuretics to try to decrease some swelling in the area. They’ve tried non-steroidals—that is something like naproxen, ibuprofen, and Advil. Vitamin B6 and oral prednisone.
What has been found is that these different drug regimes can work for a short period of time, but generally they don’t work for a long period of time, particularly the oral steroids. They will work in the short term, but it is not something that’s going to help maintain a decrease in the symptoms.
So, the next thing we look at, if just the splinting doesn’t work, is doing an injection. And we do a steroid injection right into the carpal canal. And, admittedly, it is not terribly comfortable. But the theory behind doing the injection is we put steroids right into the local area to try to decrease some inflammation around the nerve and the tendons around the nerve that should help with patient symptoms.
Again, we usually suggest splinting after we do the steroids. If the first injection is successful for an extended period of time, I’d say more than a week or two weeks, then usually, we’ll look at doing another injection.
If the injection does not improve the patient’s symptoms for more than a week, or if we do two injections and the patient still has symptoms, then we start talking about surgical intervention.
So, again, the surgery is for patients that have failed to respond to conservative measures or in patients with significant nerve entrapment. And that’s something that is, again, confirmed in those nerve conduction studies.
One of the things to note is that even in patients that have normal studies, surgery can sometimes be effective. And a lot of times we’ll confirm that based on doing a steroid injection. If that resolves the patient’s symptoms, we will still look at doing surgery if somebody has negative nerve tests.
So, the surgery itself, basically, what we’re looking to do is relieve pressure on the median nerve. And the way we do that is by releasing the transverse carpal ligament.
As you can see on the diagram on the left, that transverse carpal ligament is what’s putting pressure on the nerve. This diagram that you’re looking at right now is one of the old ways that people used to have carpal tunnel surgery done.
And patients will come in and talk to me and say, “Hey, I had a friend that had the surgery done, and they had this huge incision.”
Nowadays, we tend to make a much smaller incision. And again, the primary goal of our surgery is to release the transverse carpal ligament, and it’s the ligament of the nerve that puts pressure on it. And there are two ways we do this.
In the diagram on the left you’re looking at, there is a more modern way we tend to do an open carpal tunnel release now through a much smaller incision. Or the diagram on the right is when we do the surgery through an endoscopic approach.
Previously, patients used to leave after carpal tunnel in a splint as you see on the left or the bottom right. For the most part now, when we do carpal tunnel surgery on somebody, they leave in a small dressing, as you see on the top right.
So, a lot of times, when you approach doing the surgery for carpal tunnel, it is a surgeon’s comfort on the way they do the surgery, whether they do it open or whether they do it endoscopically.
I, over the recent years, have leaned towards doing the surgery endoscopically and it’s just my preference. I feel like it gets patients back to doing their normal activities just a little quicker than doing the open surgery. And the incision heals a little better and quicker on the wrist, where I do the surgery, than on the palm of the hand.
But, again, that is a surgeon’s preference. And when we look back, either way, you are completing the same goal, and that is releasing the transverse carpal ligament that puts pressure on the nerve.
So just to conclude all of this, carpal tunnel is the most common focal peripheral neuropathy. That means, in simple terms, that it is the most common nerve that’s affected by compression in the periphery of your body, out of the elbow, wrist, knees, foot, and ankle.
The most common complaints are pain and paresthesia in the distribution of the median nerve. So that includes the thumb, index, middle finger, and if people have actually read the textbooks, the one side of their ring finger.
And when we look at the physical exam, the Tinel’s sign that’s tapping on the nerve, and the Phalen’s maneuver, which is flexing the wrist all the way down, are the most classic signs of carpal tunnel.
Also, the other complaints are hypoalgesia, which is basically losing some of the feeling in the fingers that you feel like you’re starting to lose control and not feeling stuff. Again, one of the common complaints is people struggle doing up the buttons on their shirts or doing up the buttons on their pants because they cannot actually feel them.
Late signs include weak thumb abduction because of muscle hypertrophy. And those are often more predictive of people’s symptoms than actual nerve conduction studies.
Heather Benjamin: We have a few questions. Our first question is, “How long does the steroid injection last typically?”
Dr. Gary Millard: So, unfortunately, that again, is something we cannot predict very well. It varies from patient to patient. A lot of times the first injection is a trial. For some patients, it can last up to a week or less.
For a lot of patients, it can last up to a year or more. So, unfortunately, it’s something we cannot give an exact answer to. It is very individual as to how patients respond to the injection.
Heather Benjamin: And then, “How many injections can you have?”
Dr. Gary Millard: Generally, we try to avoid too many injections. What, unfortunately, will tend to happen is if a patient has a long period of relief from the first injection, often the later injections do not last quite as long.
And if we’ve done more than three injections and the patient’s symptoms keep returning, that’s usually when we’ll talk about entertaining the surgical intervention.
Heather Benjamin: And then, “Will my numbness go away completely after surgery?”
Dr. Gary Millard: That is a very tough question to answer, and a lot of it depends on the severity of the symptoms and the severity of the carpal tunnel before doing surgery.
What I usually explain to patients is that they will have some immediate relief. Usually, the patient’s immediate response is that they actually finally got to sleep through the night because their hands didn’t get numb on them.
If patients are numb before we do the surgery and they have severe carpal tunnel, we cannot always guarantee that the feeling is going to come back to normal. But usually, they will get improvements for about up to about three months from surgery.
Heather Benjamin: The next question is, How long does it take after surgery for the numbness to go away?”
Dr. Gary Millard: Again, I tell patients that it’ll take sometimes up to three months for most of the numbness to resolve completely. I would say at least 50% of my patients when they come in for their follow-up visits two weeks after surgery, tell me that the numbness is almost completely or completely resolved.
Heather Benjamin: “Will you do surgery on both wrists at the same time?”
Dr. Gary Millard: Generally, I do not do both wrists at the same time. That is just because I like the patient being able to take care of themselves. They do need to take care of some of their daily functions.
So I like them to have one hand that is not in a dressing that they are able to use well. I will usually do them about 2 to 3 weeks apart, but my preference is not to do them both at the same time.
Heather Benjamin: And then, “What does it mean that I have permanent nerve damage? If I have surgery, will my symptoms decrease?”
Dr. Gary Millard: Even if you have permanent nerve damage, yes, your symptoms should decrease. If somebody has permanent nerve damage, that usually indicates that they’ve had severe carpal tunnel for an extended period of time. And generally, the carpal tunnel will get progressively worse.
So, our goal is to actually take the pressure off the nerve. The first thing it does is it stops getting worse. And the next thing it does is it allows the nerve a chance to recover.
If someone’s told that they have permanent nerve damage, getting 100% function of the nerve back is unlikely. But, getting a significant amount of the recovery is possible.
Heather Benjamin: “How do you decide which hand to do surgery on first if both are bad?”
Dr. Gary Millard: I usually leave that up to the patient. If I’m going to do surgery on both hands, I will let the patient decide which hand they want to be done first.
Heather Benjamin: And then, “I have numbness in the little finger. Is this carpal tunnel?”
Dr. Gary Millard: Numbness in the little finger is usually not carpal tunnel. More often will be, if it’s in the little finger and the ring finger, it will be something called cubical tunnel syndrome, which is compression of a different nerve. It’s compression of the ulnar nerve. And that usually occurs at the elbow.
Heather Benjamin: Thank you for participating in tonight’s webinar. Thank you and goodnight.
Dr. Gary Millard: All right. Thank you!
If you have any more questions about carpal tunnel syndrome, be sure to contact OrthoNeuro today! We have many offices within Columbus, OH for your convenience. Our specialists look forward to helping you with your wrist pain.
