MASH Report: Alex Wood, Danny Duffy, and Mike Trout

Attempting to write a MASH report is like being asked to replicate the Mona Lisa. I can’t hope to do any better than what the legendary Jeff Zimmerman has done in the past – but let me try to put my own spin on things.

Alex Wood

There are a few things that come to mind when you hear about a shoulder injury in a pitcher. The first is usually the rotator cuff strain. If your pitcher was super in to dirt bikes – it might be a separated collar bone. Worse off – you might hear about a labral tear in the shoulder. However, it’s SUPER rare to hear about an SC joint strain.

To orient you to a bit of anatomy, the collar bone links your sternum to your shoulder blade via two joints – the acromioclavicular joint, and the strenoclavicular joint. If you’ve heard about someone landing hard and suffering an AC sprain – that’s a sprain of the end of the collar bone closest to the shoulder joint. The other end, and what Alex Wood is dealing with, is the SC joint.

I’ve checked with Baseball Injury Consultants, and did some rather extensive Googling, and I can’t seem to find any other cases of SC joint inflammation in pitchers. Internet, I’m sure you’re about to prove me wrong. I would expect this to be the type of injury that makes pitching very painful, but once the inflammation dies down, he’ll be no worse for the wear.

Danny Duffy

The Royals Danny Duffy has been very solid this season, pitching to the tune of a 3.54 ERA, and a 3.43 FIP. On Sunday, he went on the DL with an oblique strain that he suffered while covering first base on a grounder. The Royals have publicly stated that he could miss 6-8 weeks – and before I got into my own analysis, I found this great tweet by Shaun Newkirk.

An average of 44 days due to oblique strains is a long time to miss. I dove into the scientific literature on the importance of the obliques during pitching, and you can see why it takes so long for arms to return from this injury.

During the pitching motion, the obliques are at near 100% of their capacity (Watkins et al., 1989). These muscles are hugely responsible for torso rotation – a massively important part of the pitching motion. Without healthy obliques, velocity will fall, and pitchers will lose their effectiveness. Unless the pitcher is 100% healed from this injury, the chances are their performance will suffer.

In particular, the non-dominant side oblique is more active during motion (so for Duffy, this would be his right side). This is responsible for the torsion required to throw hard, but also, to protect the lower back from injury during pitching.

If this is a severe injury, don’t expect Duffy back until he’s completely healthy – and the process could start all over again if he is rushed back for a rehab assignment before he’s completely healthy.

Mike Trout

Having me write about a hitter is like having Roger Ebert write about a Cubs game – if he was a really marginal movie critic. Pitching has been the focus of my writing, but what does science know about the UCL tear that Trout suffered while sliding in to second base on the weekend?

This UCL is a lot less severe than the UCL associated with Tommy John Surgery – however, this ligament serves a very similar role in stabilizing the lateral bending of the thumb (compared to the elbow). This vaglus/varus motion, when in extreme force levels, can lead to a rupture of the ligament.

In the orthopaedic world, a complete tear of the thumb’s ulnar collateral ligament is referred to as a Stener lesion, or “Game Keeper’s Thumb”. Go and Google why it’s called Game Keeper’s thumb, I’ll wait.

Welcome back. Pretty messed up, eh? A review by Ryu et al., in 1995 showed there were very inconsistent results when athletes pursued non-operative treatments of this injury – and that surgical options were preferred for long term success.

This injury is associated with a very weak pitch and painful grip – which would significantly impact Trout’s ability to grasp the bat. For return to play times – the news isn’t great, but it’s not as bad as it could be. In a review by Schroeder & Goldfarb (2015), they advised a 6 to 12 week recovery time, including rehabilitation, from surgery.

For the fantasy baseball player, losing the first overall pick is a huge kick in the groin. Hopefully you can tread water before getting Trout back for September and the playoff run.

I’m going to try and do a bi-weekly MASH report from here on out – if you have any players you’d like to have reported on – hit me up on Twitter: @DrMikeSonne

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Ergonomist (CCPE) and Injury Prevention researcher. I like science and baseball - the order depends on the day. Twitter: @DrMikeSonne

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Given the Dodgers liberal use of the 10-day DL this season for what seems to be extra days off for starting pitchers…Is it possible that this inflammation is causing Wood no additional pain beyond the usual soreness following a start? Presumably every pitcher has some inflammation in their throwing shoulder following each game they play in…Prior to the season, we heard that the league was going to crack down on so-called phantom DL stints…but, it doesn’t seem like it would be too difficult to provide evidence of inflammation in the first 48 hours following a start and so, the Dodgers are simply scanning guys they want to rest/skip and catering the ‘injury’ to the most obviously inflamed region.


In the article about it, Wood said he’s had this inflamation before last year and in spring training and missed no time due to it, but this time it is a little more inflamed so they are going to give it a few days to subside.

Note that the Dodgers also had a report about Brandon McCarthy experiencing minor knee patellar tendinitis but he is making his start: they can’t have both skip starts (they’re back to back days) and, since Wood has been better than McCarthy, they’re either more worried about his or it’s more painful for him, since they’d surely rather skip McCarthy than Wood at this point.


Even with Wood’s injury history, my first thought was this was just the Dodgers gaming the system (probably because of that aforementioned injury history). What ever, it’s working.