Spin Rate: Another Benefit From Tommy John Surgery?

Once the ball leaves a pitcher’s hand, how fast it spins (spin rate), how fast it approaches the batter (velocity) and the percentage of time a batter swings and misses (whiff rate) are the three stats that usually make or break Major League Baseball pitcher’s career.

Does Tommy John surgery change a pitcher’s spin rate, velocity, or whiff ratio?

Turns out, according to a new study, Major League Baseball pitchers who undergo ulnar collateral ligament reconstruction (UCLR) do not experience any significant decreases in the spin rate, velocity, whiff rate, or hard-hit rate of 4-seam fastball, 2-seam fastball, or slider at 2 years after ulnar collateral ligament reconstruction—aka: Tommy John Surgery.

“Ulnar collateral ligament reconstruction is commonly performed in Major League Baseball pitchers, with variable reported effects on velocity and traditional rate statistics. Currently, no studies have evaluated spin rate in the context of return to play after injury. Greater spin rate has become increasingly sought after in the baseball community, as it is believed to be a vital aspect of pitch effectiveness,” the researchers wrote.

They hypothesized that in their study the post-UCLR fastball and slider spin rates, velocity, and whiff rate would be decreased compared with their levels prior to surgery, while the fastball and slider hard-hit rates would be higher in comparison with pre-UCLR levels.

The study included 36 pitchers who underwent UCLR and returned to Major League Baseball play between 2016 and 2019. The researchers used the Statcast system to collect spin rate, velocity, hard-hit rate, and whiff rate for 4-seam fastball, 2-seam fastball, and slider for pitchers in the preinjury year as well as the 2 years after return from UCLR.

Of the 36 athletes in the study, 31 of them were able to return to Major League Baseball pitching. The researchers reported no significant decreases in any of the types of pitches in spin rate, measured in revolutions per minute between preinjury levels and first and second seasons after their return.

There was, however, a decrease in velocity for the 2-seam fastball in the first seasons (92.9 vs. 93.7 miles per hour; p = .045) but not the second season (93 mph; p = .629) after return to play. Also, for the 2-seam fastball, there was an increase in spin rate between preinjury and return to play season 2 (2,173.5 vs. 2,2253 rpm; p = .022). For the slider, there was a significant increase in spin rate between preinjury and return to play season 2 (2,245.1 vs. 2,406 rpm; p =.016).

The study, “Ulnar Collateral Ligament Reconstruction Does Not Decrease Spin Rate or Performance in Major League Pitchers,” was published online on May 26, 2022 in The American Journal of Sports Medicine.

Study authors include Mark E. Cinque, M.D., M.S., Christopher M. LaPrade, M.D., Geoffrey D. Abrams, M.D., Seth L. Sherman, M.D., Marc R. Safran, M.D., and Michael T. Freehill, M.D., all of the Stanford University School of Medicine.