Hello. Thanks for staying around. Looking at these good studies, I'm going to talk a little bit about adolescent pitcher fatigue, trying to drill down on pitch counts. My disclosures. And a special thanks to all my co-authors and the research team. This is a lot involved with the logistics of this study, and I couldn't have done it without everybody. This was funded by a grant while I was at University of Michigan. So this Lyman study back in 2001 was kind of the start of the pitch count. You saw at that point 75 pitches is what they recommended from 9 to 12 year olds. And since then, we've had, you know, improvements in that. A little more structure from Little League Baseball, Pitch Smart USA. These recommendations you can see with the ages and the pitch counts and the recommended days of rest. But we also know that the reported incidence of elbow pain in young throwers starting as young as 8 and all the way through the professional levels is extremely high. We also know throwing through fatigue and pain increase your odds substantially to a pitching-related injury. And when you get into the youth pitchers, you can see 36 times the risk of injury if you throw through fatigue. So my thought that I'm very interested in is we know the flexor pronator mass is the primary dynamic stabilizer. That is protecting the UCL. If you fatigue that flexor pronator mass, the UCL is going to see more stresses. Is that the reason why we're seeing this epidemic rise in these injuries? So that's kind of the basis of where I was going with this. This is a pilot study. If you really want to get into the weeds here, we have to hone in on one age group, and that's what I did, just 10 year olds. Their pitch count recommendation, 75 pitches. Primary outcome, medial elbow laxity. Does it change? And then looking at the characteristics of the muscle itself and additional parameters as shown. So male pitchers, this was appropriately powered. 22 pitchers, all from the same travel ball organization, all 10 years old. So they'd throw 25 pitches, take a break, another 25, break, another 25. We'd get all the parameters within that. There was a structure to how much time between each pitch, et cetera. So everything was very structured here. Medial elbow laxity was measured with a Telos device. This has been published in the literature by the Andrews Group, 10 Deccan Newtons across that. One of my non-operative colleagues who's very experienced with the ultrasound did all the ultrasound measurements. We measured these together for standardization with regards to gapping. Ultrasound technology called muscle ultrasound, for those of you that aren't familiar with this, takes a look at a muscle belly and the echogenicity of that muscle belly. When you get another shot of that same muscle belly after you've worked out or fatigued it, the echogenicity change relates to how much water is there, which relates to how much glycogen is left. So you can get an energy storage percentage almost. This has been validated in the rectus femoris and the vastus lateralis. You can see here a couple of different areas that we took these shots from. Accuracy was obtained as was velocity with a Stalker 2 radar gun. Our results, so as far as medial elbow laxity went, there wasn't any change at any time point, 0, 25, 25, 50, 50, 75. There was change in the muscle belly though. Somewhere before the 75 pitch mark, there was change. So the energy is becoming less. Grip strength significantly decreased somewhere between 25 and 75 pitches. Subjective fatigue at every instance, that's to be expected, but it just goes to show you that these kids do start to tire out. Velocity, accuracy, strength and range of motion all were not significant. So the conclusions here are going up to the 75 pitch recommendation in 10 year olds, you don't see the elbow laxity increase, but you do start to see some changes in the flexor pronator mass. You also know that the subjective fatigue is worsening up to that point and the grip strength somewhere between 50 and 75 pitches significantly decreased. Thus, our findings and my recommendation, or not recommendation, but belief at this time is the sweet spot is somewhere between 50 and 75. Obviously, more work needs to be done, but this is a pilot study and we'll go from here. Thank you.

pitch counts

elbow pain

injury risk

grip strength

further research