The Impact of Health Shocks on Worker Performance: Evidence from Professional Sports

Workplace injuries generate substantial costs to workers and employers. We analyze consequences of a workplace injury, ulnar collateral ligament (UCL) damage in elbows of baseball pitchers. Once career ending, a method to repair torn UCLs, Tommy John surgery, was developed in the 1970s. We analyze performance of pitchers before and after undergoing this surgery and also compare them to a matched sample of uninjured pitchers. Surgical repair of UCL injuries extends post-injury careers by roughly one season relative to matched uninjured pitchers, generating economic benefits for players and teams. Post-injury performance, in terms of batting success of hitters faced by pitchers, improves by roughly 3%. Pitchers returning from the injury face fewer batters per season than matched uninjured pitchers.