# Timing of surgery in professional baseball—an analysis of Major League Baseball pitchers who underwent ulnar collateral ligament reconstruction

## TL;DR

This study examines how the timing of ulnar collateral ligament surgery in MLB pitchers affects their return to play.

## Contribution

It reveals that surgery later in the season correlates with a longer time to return to Major League Baseball.

## Key findings

- The rate of return to MLB after surgery was 77.9% with no significant difference by timing of surgery.
- Pitchers who had surgery in the late season had a significantly longer time to return compared to those in the early season.
- The time to return was 19.0 months for early season surgeries versus 23.0 months for late season surgeries.

## Abstract

The rates of return to the same level of play (RTSP), time to RTSP in Major League Baseball (MLB) pitchers, and missed days of the season after ulnar collateral ligament reconstruction (UCLR) have been reported previously. However, previous studies have shown a large disparity between time to RTSP and missed playing time during the season after UCLR. Additionally, the literature has not investigated the relation between the timing of UCLR during a season and the time to RTSP. The purpose of this study was to investigate how the timing of UCLR during the season affects the time it takes to RTSP.

The data of MLB pitchers who underwent UCLR between January 2012 and December 2022 were obtained from publicly available online records. The rate of RTSP, the rate of RTSP in the next season, and the time to RTSP at the MLB level were collected. The timing of surgery performed during the season was grouped into 3 categories: early season (January to April), middle season (May to August), and late season (September to December). The rate of RTSP and time to RTSP were compared across each category.

Two hundred seventy-two MLB pitchers who underwent UCLR were included. Two hundred twelve pitchers successfully returned to MLB. Overall, the rate of RTSP after UCLR in MLB pitchers was 77.9% without any statistical difference among the 3 timing categories (P = .45). The rate of RTSP in the next MLB season after UCLR was 56.7% in the early season, 37.0% in the middle season, and 4.2% in the late season. Time to RTSP was 19.0 ± 7.2 months in the early season group, 20.7 ± 10.0 months in the middle season group, and 23.0 ± 8.6 months in the late season group. Time to RTSP in the early season group was significantly faster than in the late season group (P < .001).

The timing of UCLR during the season has a significant effect on the absolute time to RTSP in MLB pitchers. Those who undergo surgery later in the season have significantly longer absolute time to RTSP than those earlier in the season.