Mets injury analysis: Jacob deGrom and his elbow surgery

Earlier this week, another Mets pitcher underwent season-ending surgery. This article will address the surgery Jacob deGrom underwent and whether he’ll be ready for spring training.

What is the injury?

The ulnar nerve stems from your neck and travels down the arm to provide feeling in the ring and pinky finger as well as movement for the tiny hand muscles and some wrist flexor muscles. As it travels down the arm, the nerve travels through the cubital tunnel—a passageway created by the bones in your elbow and the surrounding tissue—to go from the arm to the forearm. Occasionally, the ulnar nerve can rub against the medial epicondyle—part of a bone that comprises the cubital tunnel—to cause irritation. If the nerve gets repeatedly irritated, say approximatley 95-to-100 times a game, then the irritation can become really aggravated, which may cause muscle weakness and some sensation loss. deGrom has admitted that he has lost sensation in his ring and pinky finger for weeks. Unfortunately, Matt Harvey also had sensation deficits earlier this year that led to his season-ending surgery.

For this reason, surgeons will perform an ulnar nerve transposition. This essentially means that surgeons moved the ulnar nerve to another place to avoid re-irritating it. As you can see in the linked image above, the ulnar nerve is essentially pushed away from the medial epicondyle to the front of the elbow to avoid the nerve consistently rubbing over that bony prominence.

It is hard to say exactly what causes the irritation, but for whatever reason, the ulnar nerve became compressed/pinched in the elbow. It is possible that the scar tissue from deGrom’s Tommy John surgery could have grown larger and start pushing against the nerve and consequentially against the medial epicondyle. On the other hand, it could be a result of a tight nerve that may become irritated when you try to stretch it or that the nerve could have fallen out of place since the elbow is constantly moving in a pitcher. The exact cause is typically unknown in most cases, but these are some possibilities that make sense to me.

When will deGrom be ready to pitch again?

When it comes to this procedure, most pitchers do not touch a ball for 6-to-12 weeks. For this reason, a lot of stiffness accumulates in the elbow in addition to tight forearm muscles. That is the biggest issue physical therapists need to address once the athlete begins rehabilitation, typically few weeks after the surgery. Once the pitcher has regained his strength, range of motion, and joint mobility, the pitcher will then return to a throwing program before stepping foot on a mound to pitch. Given that the nerve is affected, it is imperative that deGrom regains feeling in the ring and pinky finger. A component to effective pitching is making sure the pitcher can place enough pressure on the ball with each finger; with loss of sensation, deGrom has no way of knowing if he is placing too much pressure with his ring/pinky finger resulting in a pitch that may go awry.

Overall, it can take a pitcher anywhere from 3-to-6 months to return to pitching given how long it takes to regain strength, range of motion, and most importantly sensation. For this reason, deGrom’s timeline can range from being completely healthy by spring training to returning shortly after the 2017 season begins.