I am unapologetically becoming the "baseball guy" with my
elbow, wrist, and hand discussion post today. With my past and
present experiences in the game, I am naturally curious about the
ulnar collateral ligament (UCL) and any precursors or warning
signs affiliated with pathology of the aforementioned ligament. We have a pretty thorough
assessment process with our baseball athletes and have done a fairly good job
of avoiding a large number of tears/sprains in our youth and
college populations.
I was unable to find any research evidence suggesting that anatomical markers like shoulder flexion deficit, glenohumeral internal rotation deficit and total range of motion asymmetry are directly correlated to an increased risk of pathology of the UCL of the elbow, even though I have always operated under these presumptions. There is plenty of evidence to suggest that these markers are linked to increased likelihood of "injury in overhead athletes," just not the UCL specifically.
I've used the
Functional Movement Screen and Y-Balance Test as staples in our assessment
process at my gym for a number of years now so I was excited to find that in
a study (Garrison, Arnold, Macko,
Conway, 2013) published in The Journal of Orthopaedic and Sports
Physical Therapy baseball players with UCL tears displayed significantly
impaired balance on their lead and balance legs when measured with the
Y-Balance Test. This is important information in my opinion because it suggests
that training the lower extremity and core is as important, if not more
important than focusing on popularized "prehab"
and "shoulder care" work. I'm excited to know that
these are numbers we should probably be looking at more closely in
our baseball populations.
It is my opinion
that the best way for us to prevent the increasing frequency of UCL tears is to
try and have some kind of influence on coaches at the youth level. A study
published in the American Journal of Sports Medicine in 2016 found that in
baseball pitchers aged 12-18 the mean UCL thickness was 4.40 mm in the dominant
elbow and 4.11 mm in the non-dominant elbow. (Atanda,
Averill, Wallace, Niiler, Nizarian, Cicotti,
2016) This suggests that baseball players are already beginning to
make structural changes to deal with the stresses of throwing at a young
age. Furthermore, the study found that the UCL was significantly
thicker in pitchers who threw more than 67 pitches per appearance (4.69 vs 4.14
mm), who pitched more than 5 innings per appearance (4.76 vs 4.11 mm), and who
had more than 5.5 years of pitching experience (4.71 vs 4.07 mm; P < .001).
Linear regression demonstrated that age, weight, and pitches per appearance (R2
= 0.114, 0.370, and 0.326, respectively) significantly correlated with UCL
thickness. (Atanda,
Averill, Wallace, Niiler, Nizarian, Cicotti,
2016)
This
information would suggest to me that pitchers who are taking on large work
loads at a young age are experiencing the negative consequences earlier than
those who are not forced to throw as often. I think the best way to lessen
the severity of the "Tommy John Epidemic" is to get our youth
baseball coaches to stop overthrowing their best players. Putting more
influence on player learning and development and less on winning games would be
a great way to ensure these athletes are able to play baseball for as long
as they so choose without having to go under the knife.
All
that said, I would be interested to hear any input or findings some of you
may have suggesting there are more anatomical markers for predisposition
to ulnar collateral ligament pathology.
References:
Atanda A, Averill L, Wallace M, Niiler T, Nizarian L, Cicotti M. (2016). Factors Related
to Increased Ulnar Collateral Ligament Thickness on Stress Sonography of the Elbow in
Asymptomatic Youth and Adolescent Pitchers. American
Journal of Sports Medicine, 44(12), 317.
Garrison
JC, Arnold A, Macko MJ, Conway JE. (2013).
Baseball Players Diagnosed with Ulnar Collateral Ligament Tears Demonstrate
Decreased Balance When Compared with Healthy Controls. Journal
of Orthopaedic and Sports Physical Therapy. 43(10),
752-758. doi:10.2519/jospt.2013.4680