%0 Journal Article %T Return to Play and In %A Ajaykumar Shanmugaraj %A Asheesh Bedi %A Chetan Gohal %A Edwin R. Cadet %A Nicole Simunovic %A Nolan S. Horner %A Olufemi R. Ayeni %A Ryan P. Coughlin %J The American Journal of Sports Medicine %@ 1552-3365 %D 2019 %R 10.1177/0363546518798768 %X Injury to the ulnar collateral ligament of the elbow is relatively common among baseball pitchers. Ulnar collateral ligament reconstruction (UCLR) has revolutionized the management of this injury, allowing a greater proportion of pitchers to return to play. To assess the return to play and in-game performance specific to baseball pitchers who have undergone primary UCLR. Systematic review. This review was conducted according to the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The electronic databases MEDLINE, EMBASE, and PubMed were searched for relevant studies, and pertinent data were abstracted. Only studies reporting in-game performance statistics (earned run average [ERA], pitching velocity, innings pitched per season, etc) of pitchers after UCLR were included. The methodological index for nonrandomized studies (MINORS) was used to assess study quality. A total of 14 studies and 1520 pitchers were included in this systematic review. All studies were of level 3 or 4 evidence, and the mean ¡À SD MINORS score was 14.4 ¡À 3.0, which indicates fair quality of evidence for nonrandomized studies. The rates of return to any level of pitching after UCLR ranged from 79% to 100%. Subgroup analysis revealed that 79% to 87% of Major League Baseball (MLB) pitchers returned to preinjury levels of pitching. The mean time to return to play was 19.8 ¡À 13.5 months, and the mean time to return to competition for MLB pitchers was 17.3 ¡À 2.4 months. Of the 5 studies reporting ERA, 2 cited a significant increase after UCLR, and 1 indicated a significant decrease. Of the 4 studies reporting fastball velocity, 3 cited decreased pitching velocities after UCLR. All studies found that pitchers pitched, on average, fewer innings per game or season after UCLR. There was a high rate of return to pitching after UCLR. However, most studies showed that UCLR was associated with a prolonged recovery and significant decline in pitching performance as objectively measured by in-game statistics. The strength of these conclusions is limited by the quality of the available literature and inconsistencies in the reporting of outcomes %K baseball %K elbow %K pitchers %K return to sport %K ulnar collateral ligament reconstruction %K performance %U https://journals.sagepub.com/doi/full/10.1177/0363546518798768