Wednesday, August 10, 2011

Surgery or rehab for Kyle Gibson?

Last night, not long after the Twins put Scott Baker on the DL with a strained flexor muscle, they  announced that 2009 first round draft pick Kyle Gibson was going to report to Fort Myers after he was diagnosed with a strained flexor muscle as well as a partial tear in his ulnar collateral ligament.

Gibson was a pitcher on the fast-track in the system, moving swiftly through the minors and performing extremely well along the way. Armed with a slicing two-seam fastball and an impressive change-up, it was easy to see what the six-foot-six right-hander was succeeding in Rochester and knocking on the door in Minnesota. He was the owner of the International League’s second-highest ground ball rate (57%), ninth-highest strikeout percentage (21.7%) and tenth-highest FIP (3.73). Now, it appears that his arrival to Minnesota will be delayed.

While a completely torn UCL would have necessitated Tommy John surgery right away and costing him 12-to-18 months of development, in the case of partial tears to the UCL, experts have often recommended a path of rest followed by rehab lasting 12-to-18 weeks total before re-evaluation. However, it is a song-and-dance fans have seen before – most recently with Pat Neshek – in which the staff and front office says Pitcher X is going to attempt to get some R&R before the inevitable date with Dr. New Elbow and wasting several weeks of time in the process. The question is how often do pitchers have success with this route?

According to an article by Baseball Prospectus’s Ben Lindbergh, the odds are not terrific. Lindbergh cites a Corey Dawkins’ article on the subject in which he wrote:
The UCL does not completely heal on its own ever. Without surgery, the area is only stabilized by two methods. First, the elbow can be strengthened up to the point where the muscles take up the slack for the lack of ligament stability. The other method is that scar tissue is built up and the muscles are also strengthened. Regardless neither of these actually heal the tissue of the ligament, they merely control the symptom of instability.
Lindbergh approximated that 55 percent of pitchers who have gone down the path of rest & rehab have eventually made an appointment to have their UCL replaced. That list includes the Neshek who went almost a year in his rehab before requiring Tommy John surgery that all but ended his career in Minnesota. On the other hand, Lindberg notes that the Angels’ Ervin Santana followed the R&R program and wound up returning to pitch without yet running back to the surgical table. In fact since his 2009 shutdown Santana has logged 388 innings, compiled a 25-18 record with a pristine 3.62 ERA and solid 306/116 strikeouts/walk ratio.

So there is hope for Gibson in that regard. But the other concern is that Gibson has less than optimal mechanics – the kind that puts added stress on this area. Even if the Twins rest him for a while to the point where he stabilizes his UCL, it is likely that his mechanics would jar that bugger loose again anyways.

Way back in December of 2008 – long before a forearm stress fracture sidelined him at the end of the 2009 season – Kyle Boddy of the now-defunct Driveline Mechanics website deconstructed Gibson’s mechanics. Boddy found that Gibson’s leg kick was wasted motion as he lowered it before driving forward, minimizing hip force and putting added exertion on his arm. What’s more is that Gibson brings his elbow to the point of hyperabduction while scap loading (drawing his pitching arm off of the driveline of home/second instead towards first). In the video below taken by 1500ESPN’s Phil Mackey in Fort Myers this spring, while the visibility is not perfect, you can see some of the elements that Boddy was referring to including the leg motion and scap loading of his pitching arm:

It’s a difficult decision, no doubt. If you opt for Tommy John now and you have lost a year or more to development at a critical time. On the other hand, if you attempt to rest and rehab, Gibson could lose a few months before requiring Tommy John surgery anyways. Now the waiting game begins with their top prospect.