Estimating economic impacts of Tommy John surgery on Major League Baseball pitchers

Abstract

Tommy John Surgery is a common elbow surgery among baseball pitchers that has become more prevalent over the last two decades. In this thesis, I estimate the impact of Tommy John Surgery on Major League Baseball pitcher productivity and value to the team, measured through Marginal Revenue Product. Tommy John Surgery requires a rehabilitation period of over a year on average, and it is important for the team to be able to predict the pitcher's post-surgery performance. The estimated productivity impact of Tommy John Surgery is a decrease in pitchers' performance for at least two seasons following their return to play. The combined magnitude of this decrease in performance translates to about one team win and over an $800,000 decrease in Marginal Revenue Product for the team. I estimate the entire cost to a team resulting from lost productivity related to Tommy John Surgery to be about $2 million. With an average of 25 Tommy John Surgeries a season in Major League Baseball over the last five seasons, these costs total approximately $50 million league wide every year. Other components of this thesis include analyses of Wins Above Replacement as a productivity statistic in baseball and the impact of Tommy John Surgery on pitcher performance, measured through both Wins Above Replacement and standard pitching statistics, such as innings pitched and earned run average.