TCB Daily Boil: High School Arms and Injuries

Tommy John continues to be in the news this week as the baseball world continues to figure out why there is this sudden spike in surgeries to repair failed Ulnar Collateral Ligaments. Hat tip goes to clack for sending this link out to the TCB staff, which I quickly called dibs on to write about.

It's a very interesting article from Tom Verducci discussing the sudden rise in TJ surgeries and how we are not looking at the source of the problem, the amateur levels. More specifically, the high school levels as the real culprit of unnecessary stress on pitcher's elbows. We discussed last week on the role of year round baseball and velocity over 85 in high school being significant risk factors for tearing the UCL, according to Dr. James Andrews. Verducci cited ASMI research showing 85 MPH being a threshold as well along with youth pitchers exceeding 100 innings in a calendar year being risk factors.

Verducci also discusses how the culture of amateur baseball has changed over the last several years with continued emphasis on the radar gun and year round baseball. All of which he concludes have lead to significant increased stress on elbows that have resulted in injuries of elite pitchers early in their professional careers.

You will not find me disputing that.

I will however dispute to some extent the actual foundational problem of the injuries.

Does throwing hard increase the valgus force placed on the elbow? Yes

Does throwing more often reduce recovery time? Yes

But, is the problem actually throwing hard and throwing more often? Yes? And no.

How many high school pitchers have you heard of that have "perfect" or "advanced" mechanics? Very few and far between. You'll hear them described as "clean" or that their "arm works." But, what do even those pitchers talk about after their first year's in the minors? Working on their mechanics.

You see, it takes several thousand repetitions for the human body to truly establish a neuromuscular firing pattern. Now, you are asking a developing body that is increasing in height, weight, strength, muscle, and every thing else, to create a consistent neuromuscular firing pattern? A complex pattern of human movement that relies heavily on timing with an ever changing human body?

It's doesn't makes sense for them to do that year round. They haven't built up the consistent delivery to establish that neuromuscular firing pattern consistently enough to compete year round. I have no problem throwing year round, my issue lies with year round competition because that increases the stress because pitchers are trying to impress college coaches and pro scouts which tends to rush deliveries and attempt to throw harder.

I struggle with the velocity aspect though. As a statistical oriented blog, we love our advanced metrics and sophisticated analytics. However, we have to recognize that our statistical outcomes are only as good as our statistical input.

What do I mean? If you take a sample of 100 youth pitchers that throw anywhere from 80 to 95 and try to figure out that threshold being at risk for UCL tears, that's great. But, have you truly controlled for other influences? Not in the least amount.

We know that shoulder abduction over about 100 degrees at foot strike increases stress on the UCL. We know that early trunk rotation increases stress on the UCL. We know that elbow flexion less than 90 at foot strike also increases UCL stress.

Are you seeing where I'm going with this?

Young pitchers do not have great mechanics? They don't have great firing patterns. Some do, but the majority don't. The problem is, to find pitchers that throw in those ranges and do not have those mechanical flaws are few and far between, making our sample size too small to create statistical significance in most cases.

I have no problem with amateur pitchers that throw that hard, as long as they are clear of other red flags that have been shown to increase stress on the elbow. But, I am against year round competition in most cases. I do like that 100 inning threshold in a calendar year.

Of course, I need to foray this into an Astros discussion. That path leads to the draft. Lets consider some HS seniors that are being considered in this years draft at the 1-1 selection. Brady Aiken and Tyler Kolek.

Brady Aiken took the winter off and didn't pitch. He came back this spring with a velocity bump into the mid-90's and has seen his stock rise.

Tyler Kolek frequented the showcases over the fall and winter and peaked at 99 MPH and has found his way into top 5 status.

With two places showing research that 85 MPH is a threshold for increased risk of UCL injury and year round baseball also being a risk factor, does your opinion of either pitcher change?

Does this scare you away from HS pitchers even more? Does it make you want to go back and do research on how the college arms were used in their years as high schoolers?