Summary

NBA players have a relatively high rate of RTP following ACL-R however players do suffer a significant decrease in performance as evaluated by PER in their first season post injury

Abstract

Objectives
Anterior cruciate ligament (ACL) injuries are increasingly common in elite level athletes. While return to play rates are traditionally reported as being high, subsequent performance following injury is potentially even more important, especially in professional athletes. Both predicted and reported subsequent performance can have significant financial implications for players and teams depending on the trajectory and time point of a player’s career. The objective of this study was to determine return to play and player performance in the first and second season following ACL tear in National Basketball Association (NBA) players.

Methods

An online database of publicly available NBA athlete injuries between 2010 and 2019 was queried for “ACL reconstruction.” These results were confirmed using NBA team websites, publicly available Internet-based information, and press releases when necessary.
Information including name, age at injury, team, position, height, weight, body mass index (BMI), handedness, NBA experience, date of injury, date of surgery, date of return, knee affected, and seasons played post-surgery was recorded for each player. Regular season statistics for one season before surgery and the two seasons immediately after surgery were compiled. Games started, games played, minutes played, and player efficiency rating (PER) were recorded for seasons prior to and after surgery.
Mean, range, and 95% confidence intervals characterized player demographics and characteristic data. Kaplan-Meier survivorship plots were computed for athlete return to play and retirement endpoints with shaded 95% confidence intervals. Statistical analysis was performed using RStudio, Version 1.1.442 (RStudio Inc. Boston, MA). And a value of .05 was used.

Results

A total of 26 athletes underwent ACL reconstruction (ACL-R) between 2010 and 2019. Athletes had an average BMI of 24.6 kg/m2 (range 20.9-26.9 kg/m2), age at injury of 25.3 (range 19.0-38.0), and average playing experience of 4.77 seasons (range 1-14 seasons). 84% (95% CI 63.9-95.5%) returned to play. The athletes returned to play on average 372.5 days (95% CI 323.5-421.5 days) after surgery with a career length after injury on average 3.36 seasons (95% CI 2.27-4.45 seasons). The earliest return to play was at 230 days following surgery.
Performance was assessed both via percent of games played following injury, and the relative percent change in PER. Athletes following ACL-R played in fewer percent of games in both the first season post-injury (48.4%) (p=0.0004) and the second season post-injury (62.1%) (p=0.0067) compared to the pre-injury season (78.5%). PER showed that performance in the first season post-injury was significantly less than that of the pre-injury season (p=0.0056), as players had a 19.3% decrease in PER. The performance in the second season post-injury was not significantly different than that of the pre-injury season (p=0.3481).

Conclusions

NBA players have a relatively high rate of RTP following ACL-R however players do suffer a significant decrease in performance as evaluated by PER in their first season post injury. However, these players tend to return to baseline performance by the second season after ACL-R. Therefore, it may take longer than previously reported for elite level athletes to return to their pre-injury performance.