Retrospective Cohort Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Nov 18, 2021; 12(11): 833-841
Published online Nov 18, 2021. doi: 10.5312/wjo.v12.i11.833
Preseason elimination impact on anterior cruciate ligament injury in the National Football League
Michael Patetta, Benjamin Mayo, Omar Zaki Martini, Breanna Sullivan, Leonard Onsen, Mark Hutchinson
Michael Patetta, Benjamin Mayo, Omar Zaki Martini, Breanna Sullivan, Leonard Onsen, Mark Hutchinson, Department of Orthopaedics, University of Illinois Chicago College of Medicine, Chicago, IL 60612, United States
Author contributions: All authors solely contributed to this paper.
Institutional review board statement: This study was exempt from institutional board review as it was conducted using publicly available information.
Informed consent statement: This study does not require informed consent statement.
Conflict-of-interest statement: None of the authors feature potential conflicts of interest nor have they received any sort of support to carry out this study.
Data sharing statement: No individual participant data was shared.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Omar Zaki Martini, BSc, Research Fellow, Department of Orthopaedics, University of Illinois Chicago College of Medicine, 835 S. Wolcott Avenue E270 MSS MC 844, Chicago, IL 60612, United States. omarti29@uic.edu
Received: June 6, 2021
Peer-review started: June 6, 2021
First decision: July 28, 2021
Revised: August 3, 2021
Accepted: September 15, 2021
Article in press: September 15, 2021
Published online: November 18, 2021
Processing time: 162 Days and 9.8 Hours
ARTICLE HIGHLIGHTS
Research background

In 2020, the National Football League (NFL) preseason was eliminated due to the coronavirus disease 2019 pandemic. The purpose of this study was to determine if this unique elimination of the preseason resulted in a change in incidence of anterior cruciate ligament (ACL) tears.

Research motivation

Prior to the pandemic, there had been many discussions regarding the need of the NFL preseason, with the main concern being player safety. Our goal was to obtain relevant data on the impact of the preseason on ACL injuries that can be used for future discussions around that topic.

Research objectives

The main objective of this study was to compare the incidence of ACL tears through the first eight weeks of the 2020 NFL season to the mean incidence over the previous 5 seasons (2015-2019) and determine if there was any change in incidence in 2020. Though this objective was realized, this data can be strengthened if future studies are performed for a greater number of NFL seasons, as we were only able to obtain 5 years of data for this study.

Research methods

NFL players who sustained ACL tears during the preseason and first eight weeks of the NFL season from 2015-2020 were identified using online publicly available data. The number of ACL injuries for the 2015-2019 seasons was compared to the 2020 season.

Research results

A 118.8% increase in ACL tears was noted through the first four games of the 2020 season in comparison to the previous 5-year average over the first four regular season weeks of 2015-2019. However, when accounting for injuries occurring during the preseason from 2015-2019, there were 18.6% fewer ACL injuries through regular season week 4.

Research conclusions

There may be front-loading of injuries over the course of an NFL season, such that players may be more prone to injury when the intensity of play suddenly increases, whether in the preseason or regular season. This study also suggests that although the elimination of the preseason results in similar rates of ACL tears overall, it is correlated with increased ACL tears in the first four weeks of the regular season.

Research perspectives

Future research should be performed comparing the 2020 NFL season with a greater number of NFL seasons, as further data is needed to obtain more definitive results. Additionally, warm-up training has not been studied extensively in American football and is certainly a topic that should be studied for ACL injury prevention.