Tommy John is a name associated with the game of baseball not just because of the pitcher's Hall of Fame career, but because it has become synonymous with a devastating injury to the Ulnar Collateral Ligament of the elbow that continues to plague baseball pitchers often resulting in reconstructive surgery colloquially known as the Tommy John Surgery. Multiple risk factors have been postulated to put the UCL at risk of rupture including increased velocity, torque across the elbow, baseline stiffness in the shoulder and/or elbow, pitch volume, and pitch type. Well known for their extensive work in baseball science, Dr. Glenn Fleisig, PhD from the famed American Sports Medicine Institute in Birmingham, AL and Dr. Peter Chalmers, MD from the University of Utah in Salt Lake City join us to discuss their study that looks at these risk factors in professional baseball pitchers.