Understanding Jacob deGrom’s Nerve Damage

Nerve damage — something that sounds bad, and usually is

The Daily Stache

Elbow surgery: two terrible, ugly, why-would-you-say-that?! words. They’re the equivalent of, “You play ball like a girl” from The Sandlot in that, when you’re sitting face-to-face with someone and they say it about a pitcher, you know you heard it but wish you didn’t.

And the track record surrounding it is dubious at best. With every pitch, pitchers are already doing something they’re simply not meant to do. When their ulnar collateral ligament pops, it’s like their body is saying, “Come on, man. Take the hint.”

Jacob deGrom already underwent Tommy John surgery back in 2010. His first two years in the majors marked a major recovery success story; one for which there are dozens and dozens that don’t go so swimmingly. So when you hear he’s having elbow pain again and that he’s going to have elbow surgery again you get concerned, right?

DeGrom went under the knife to repair his right elbow for the second time in September — for ulnar neuropathy. Scar tissue had developed around his UCL, pinching it and causing pain. The medical term for this is “ulnar entrapment.” You might hear people saying, “It’s common” after Tommy John, but “common” is too easily mistaken for “okay” when it comes to pitchers and their elbows.

The UCL controls sensation in the ring and pinky fingers as well as the palm and underside of the forearm. In regards to pitching, most pitchers will primarily use the index, middle fingers, and thumb. Part of me wants to think that working with a tingling in your palm or even forearm would be possible to a certain extent, but the ring and pinky fingers act as support beams. Pitching without one’s stability is like watching Property Brothers: Jonathan will inevitably tell you something is wrong with a load-bearing wall and you’re not up to code. Not! Up! To! Code!

Regarding deGrom and his arsenal, the instability in his hand might have manifested in his mentality when ahead.

Statcast

He used his two-seamer in 2016 nearly five percent more in those situations than he has since reaching the majors. That’s not an insignificant number — it equated to him throwing it about 110 times more through the course of the year, or four or five times per start on average. It’s possible that instead of attacking hitters and trying to strike them out, he was perfectly content letting them put it on the ground and having his fielders take care of business. That’s not necessarily a bad thing, but it could shed light on his decreased K% and increased ERA.

Early reports out of spring training are that he’s back to the deGrom of 2014 and 2015. His velocity is the same or better than last year, he’s barely allowed any runs, and he’s striking out a ton of hitters. And while “nerve damage,” “elbow surgery,” and “it’s common” might all be phrases that can give pause, deGrom seems poised to continue being an exceptional case in Tommy John recovery.