The Strange Shoulder Injury That is Sidelining MLB Pitchers

Learn more about the injury that caused two starting pitchers to get season-ending surgery.

Matt Harvey, All-Star pitcher for the New York Mets, recently announced that he will undergo season-ending surgery. The culprit? Thoracic Outlet Syndrome.

And he's not alone. Fellow big league pitcher Phil Hughes also underwent surgery to correct the same problem, and Drew VerHagen landed on the 15-day disabled list but is hopeful that his injury won't require surgery.

So what is this injury that suddenly appears to be sidelining MLB pitchers? We spoke with Dr. Patrick Vaccaro, director of vascular diseases at The Ohio State University Wexner Medical Center, to find out.

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STACK: What is Thoracic Outlet Syndrome?

Dr. Vaccaro: The thoracic outlet is located between the collarbone and first rib, and there are three structures that run through it. Pressure from hypertrophy [growth] of muscles, repetitive activity or the way you were born can put undue pressure on these structures. Ninety percent of the time it's pressure on the nerve, about 6-7 percent of the time it's pressure on the vein and the remainder is pressure on the artery. It's probably more common than people think , and we do have excellent treatment for it.

Thoracic Outlet Syndrome

Image courtesy of The Ohio State University Wexner Medical Center

What causes Thoracic Outlet Syndrome?

We see it in people who do a lot of repetitive activity. I've operated on a number of baseball pitchers, tennis players, volleyball players, swimmers and bodybuilders. Especially in high performing athletes, they throw and do things at an incredible speed. The amount of pressure that can build up can cause a lot of wear and tear and can result in Thoracic Outlet Syndrome. There was a pitcher many, many years ago by the name of J.R. Richards, and he had this condition. That's one of the earliest cases I remember being mentioned in an athlete.

There's nothing you can hang on by just looking at someone and say they will be at an increased risk, other than the activity. However, we know that people who do repetitive arm motion are at an increased risk of developing it.

What are the symptoms?

It can be anything from a nuisance with some numbness and tingling to ulnar nerve pain that goes along the course of the lateral arm and down to the fourth and fifth fingers. It can feel like an electric shock when you're throwing very hard and lead to numbness of the fingers. If you have numbness, you won't be able to throw a baseball very well.

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What is the most effective treatment?

Matt Harvey

If it's related to pressure on the nerve, we get them into physical therapy and see if we can improve their posture and shoulder strength and open up the thoracic outlet. About a third will improve, but that leaves about two thirds who don't, and those are the people we end up taking out the first rib. You can either make an incision in the armpit and slide up the chest wall and take it that way, or make an incision above the collarbone. Most of the time I go through the armpit because it hides the scar. For some people, I like to go above—it depends on what you are treating specifically.

What's the recovery process like?

I have most athletes that I deal with back to full activity in eight weeks. But for an athlete who performs at an elite level, they are going to take a bit longer, as they generate more energy in their motion. And you need to make sure they don't re-injure themselves. They could tear adhesions and cause bleeding in the space, and that results in a reaction that creates more scar tissue and leads to more problems.

How will it permanently impair an athlete's performance?

You should be back to full activity and perform every bit as good as before. In some people, they have early arm fatigue and have a drop in their velocity from Thoracic Outlet Syndrome. After they treat it and get rid of the discomfort, they get their velocity back again.

How can an athlete avoid Thoracic Outlet Syndrome?

You never know when it's going to happen. There's nothing that can predict it. You want people to try to have good posture, which is something that will help a little bit. You're mom telling you not to sit with your shoulders slouched—that's something that can be helpful. But you're just not going to know who will develop it. You could have two people side by side who look the same and one person will develop it and the other one won't.

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