Thursday, May 12, 2005
The flexor pronator muscle mass. A bundle of muscle fibery joy that most of you ignorant folks have never heard of. OK, most of you normal human beings who have never taken anatomy classes focusing on musculature* have never heard of. It's the thing(s) that Troy Percival has (have) injured. The Tigers official site is saying that he has a 'partial tear of his right flexor pronator muscle mass'.
I've seen a fair amount of chatter about how the big risks the Tigs took this offseason are killing them, or how smart holding onto Ugie seems now, and how OMFG IMA KILL THAT BITCH DOMBROWSKI HE A-RUININ' OUR SEASON WIT HIS FANCY IDEARS OF WHAT MAKES A GOOD FREE AGENT, but I haven't seen anyone talking about what the hell the flexor pronator muscle mass is, or what it means that Percy has hurt it, or anything like that.
Who better to enlighten us all than an art student with no medical knowledge whatsoever? Hey, if I can draw it (see above nattily labeled 'medical illustration'), I can talk about it! I poke dead sharks with pokey metal bits! I am teh smart!
First off, let me say that the Tigers are releasing very little information about the damage that Percy's done here, much like the Sox have been doing with Schilling-- the "It's just a flesh wound!/Black Knight" syndrome, in part, and in part to keep fans from panicking, although would Detroit really panic over this? Relief pitcher on the DL, let's burn the city again! No, that's much more likely in Boston, but since I don't think we've ever burned Boston to the ground, you could say... uh... let's drown the city in molasses again!
Anyways. I mean, the flexor pronator muscle mass, as best as I can tell, is a collection of muscles, not any one single muscle. So when they say that he has a 'partial tear' of this, do they mean he partially tore all of them? Tore a couple and left some intact? Ripped some connective tissue but left actual muscle mass untorn? I don't know, so it's hard to say exactly what impact this will have on Percy.
What does the flexor pronator mass do? As the name suggests, various muscles in the group aid in flexion and pronation of the hand and forearm. Flexion is exactly what it sounds like (bending at the joints, you know), and pronation is the rotation of the arm so that the palm of the hand faces downwards towards the ground when you're holding your arm out in front of you, like the way you would hold it to condescendingly and dismissively pat the head of a misguided child who said that he thought A-Rod was the best player ever.
The flexor carpi ulnaris is responsible for flexion of the wrist and pulling the wrist towards the ulnar side (moving the hand laterally towards the outside... er, like away from your thumb, only not, because the thumb is attached and going along for the ride, but you know what I mean). The palmaris longust is responsible for flexion of the hand, and is the weakest muscle in the group. The flexor carpi radialis is responsible for flexion of the wrist and inward (thumb-side) rotation of the hand. The pronator teres is responsible for pronation of the forearm and helps in flexion of the forearm from the elbow joint. The strongest muscle of the group, the flexor digitorum sublimis, is not pictured in the above diagram because it's a deeper muscle and can't be seen from the surface... it's responsible for the flexion of the middle and distal phalanges of the fingers and also some wrist flexion.
Obviously these (flexion and pronation) are both motions that are important to a pitcher, but Will Carroll has an interesting little entry up about the importance good pronation has on a pitcher's arm health. Basically, good pronation makes a pitcher much less likely to blow out his elbow with his curveball. Carroll asks you to hold a hammer and use it to mimic curveball-throwing, and it's a fun exercise to see what he means about pronation. It's even more fun if you imagine you're using the hammer to beat someone who deserves it.
Blue Cats and Red Sox: *brandishes hammer gleefully*
Keith Foulke: *quails*
BCRS: Ha ha! Fear my hammery wrath, gopher ball boy!
Foulke: Oh my gosh, please don't dash my brains out!
BCRS: *violently bangs about with the hammer*
BCRS: Shut up, bitch, I'm learnin' about pronation!
Anyways, I did a little judicious research on the flexor pronator muscle mass. When it comes to a pitcher, it's mostly important in how it relates to the elbow... it seems to have less problems with wrist flexion, and more with elbow pronation.
There's this important ligament, called the ulnar collateral ligament (UCL), which is the primary stabilizing ligament of the elbow for a pitcher. Sometimes pain will show up in the flexor pronator muscle mass because it is acting as a secondary support to an injured or failing UCL.
Since we don't know exactly what's wrong with Percy, I'm worried that this is a possibility. He may not need surgery for a partially torn flexor pronator muscle mass, but there could be trouble if he's wrecked his UCL.
You know what a wrecked UCL means? Yup. You guessed it (or not, but I'll give you guys the benefit of the doubt).
Tommy John surgery.
There's also the possibility that he's been throwing his curveball with poor mechanics, repeatedly stressing his arm in a particular way that can pull his elbow joint apart. I know Percy had that trouble with an inflamed elbow last year, but I don't know what it was exactly. If it was anything along these lines, his UCL could have stayed intact, but wouldn't have been able to support his arm medially (on the side facing in to his body) at all, and the flexor pronator muscle mass would have been open to strain. If his current injury is in fact solely to his flexor pronator muscle mass, this could be the reason for it. After long years of abuse (which Percy has certainly had), a single hard throw can cause this sort of injury, which would also tally with the story of him hurting himself while warming up.
It's hard to say anything further... this is all just the idle speculation of someone who knows less about medicine than Manny Ramirez knows about the gender distinction characteristics of myrtle warblers anyways. I just thought it was an odd injury, not your basic 'fatigued elbow' or 'frayed rotator cuff' or 'exploded knee' or 'Nomared groin' or 'errrrm, parasite' sort of thing, and it seemed like someone ought to at least attempt to take a look at it.
If that attempt gave us an excuse for more bad drawings, then so be it!
By the way, kids, in case you couldn't guess, this is what happens when both your teams have an off-day at the same time. *insane twitch*
And since I can't think of a good way to close this out,
Ovenbird! Seiurus aurocapillus. Click for big. Ovenbirds are awesome. And they don't throw sketchy curveballs. So everyone wins.
*Obviously art anatomy classes focus on skeletal and muscular structure. No sense in studying anything except what you can see.