Matt Harvey has elected to have season ending surgery to treat his thoracic outlet syndrome. This primer will cover the nature of the injury and how it affects Harvey moving forward.
What is Thoracic Outlet Syndrome?
Thoracic Outlet Syndrome (TOS) is compression of the nerves and/or arteries that leave the neck and go to the shoulder. As a result, sensation and/or blood flow to the hands are cut off causing symptoms such as numbness and tingling, weakness, and muscle atrophy. It is far more common for nerves to be compressed than arteries. It is a very complex condition to identify and treat as these symptoms are clinically common in more prevalent conditions.
How does one get TOS?
There are several ways to get TOS because there are many structures between the neck and shoulder that can play a role in compressing the subclavian artery and brachial plexus (the group of nerves that branch out from the side of your neck and go to your shoulder to provide sensation throughout your arm and activate the muscles of the shoulder, elbow, forearm, and hand). The most common site of compression is between your first rib and clavicle (aka collarbone). Another possible method is that the hypertrophy of some of your neck muscles (called the scalenes) compresses those structures whenever you move your head. Finally, as you lift your arm to the side, part of the shoulder blade (coracoid process) can pinch those structures against one of your chest muscles (pectoralis minor) creating another way to cause the compression. Any one of these methods is possible for Harvey.
What will recovery look like for Harvey?
Even if Harvey did not elect to have surgery, he would have been out for a significant period of time. TOS is a treatable condition, as rest will help ease the symptoms but will eventually return if physical therapy and/or medical treatment is not maintained.
Physical therapy will teach Harvey about appropriate posture and body mechanics during everyday tasks to better utilize the smaller muscles in his neck, back, and shoulder while teaching him to not overuse his upper trap and other neck muscles. Exercises are given to strengthen the muscles in between the shoulder blades and the muscles at the back of the neck. In addition, stretches can be given to loosen up tight neck or chest muscles alongside manual therapy techniques to supplement the stretches. Manual therapy techniques can involve adding more mobility to the first rib to allow more space underneath the clavicle or trigger point release to loosen up the upper trap or scalenes. It is very important that the shoulder blades move appropriately as the arm moves, so this is a body part that physical therapists will pay attention to on top of the neck and shoulder.
A possible reason Harvey's neck muscles have gotten so big is because Harvey is not breathing properly. This means that instead of using his diaphragm to inhale and exhale, he is primarily using his chest/neck to help expand his lungs. Physical therapy can educate about proper breathing mechanics and provide exercises that will reinforce using the diaphragm more to breathe in and out.
What is the surgery procedure and recovery?
The surgery Harvey is getting is called a first rib resection. This means that surgeons will remove the first rib to decompress the nerves and/or artery. They may also address the scalenes if these muscles are contributing to the problem. A botox injection can be given to "turn off" the muscles or surgeons can also remove one of the three scalenes. It is hard to project how long the complete recovery process will be as TOS is very tricky to begin with, but Mets' GM Sandy Alderson said he expects Harvey to return to pitching about four months after surgery.