Brief Summary
John Baumann, Ashwin Garlapaty, James Cook, and Steven DeFroda
Although knee injuries are frequent in the NFL, quadriceps tendon (QT) and patellar tendon (PT) tears, while less common, can severely hinder a player's career. Existing research indicates that even with surgical intervention, athletes rarely regain their prior performance levels. Given the crucial role of these tendons in high-impact sports like football, there is a need for updated studies on the risk factors, incidence, and long-term effects of QT and PT tears in NFL players. Current research on quadriceps and patellar tendon tears in the NFL is limited despite their significant impact. This study aimed to analyze the incidence and effects of these injuries from the 2009-2010 to 2022-2023 seasons. The authors also investigated how player and injury characteristics, such as position, BMI, and tear severity, influence injury risk, return to play (RTP), and performance.
The study analyzed NFL injury data from the 2009-2010 to 2022-2023 seasons to identify all reported PT and QT tears. Initially, Pro-Football-Reference.com injury reports were reviewed, identifying players listed as "out," on injured reserve, or physically unable to perform due to related injuries. The NFL's mandatory injury reporting system, which includes practice, game status, and in-game reports, ensures transparency regarding injury incidence. Further details on identified PT and QT injuries were gathered from online league and player databases. This included player demographics, injury characteristics, and tear severity, which was classified using publicly available reports as strain (grade 1), partial tear (grade 2), or complete tear/rupture (grade 3). Surgical intervention was used to infer grade 3 severity when specific tear details were unavailable. Injury dates, treatment types, and surgical dates were also collected, following established research methodologies.
Over 14 NFL seasons, 56 PT tears and 24 QT tears were identified, with PT tears occurring more than twice as frequently (4.0 vs. 1.7 per year). While QT tear incidence showed a slight downward trend, PT tear incidence trended slightly upward. QT tears were associated with higher player BMI and age. Risk factors for QT tears included BMI ≥31, age ≥26, and ≥4 years of NFL experience, none of which were significant for PT tears. Offensive and defensive linemen had significantly higher QT injury risk, and offensive linemen had higher PT risk. Both injury types occurred more frequently in games and the regular season. QT tears were also more common in the first half of the regular season.
Of the extensor tendon injuries analyzed, 96.3% resulted in season-ending outcomes. The return-to-play (RTP) rate was slightly higher for QT tears (58.3%) compared to PT tears (55.4%). Notably, a larger proportion of players with QT tears returned to their previous performance levels, often within the subsequent season. For QT injuries, no significant correlations were found between player or injury characteristics and RTP or performance recovery. Conversely, for PT injuries, players with over four years of NFL experience showed a higher likelihood of RTP. Players aged 26 or older, with over four years of experience, and those in defensive positions, particularly defensive linemen, were more likely to return to their pre-injury game participation levels.
This study has limitations, primarily due to its reliance on public databases, which may have led to underreporting of extensor tendon injuries and limited detailed injury information. However, the use of multiple databases, NFL injury report consistency, and extensive player/team data helped maximize injury capture. Furthermore, the author's findings align with previously reported injury rates and proportions.
This study's results expand upon prior research regarding extensor tendon injuries in the NFL. The observed rates of QT and PT tendon injuries were higher than those reported in studies spanning 1994-2004, suggesting a possible rise in these injuries in recent decades. The return-to-play (RTP) rates, around 55% for both QT and PT injuries, were similar to past findings for QT injuries but significantly lower than the previously reported 79% RTP rate for PT injuries. This discrepancy indicates that patellar tendon injuries may now have a more detrimental effect on NFL player careers than previously recognized. Returning an athlete's maximal isometric strength and rate of force development to pre-injury baselines can have a significant impact on return to play and performance. For more information on baseline isometric screening, longitudinal isometric monitoring and isometric training within rehabilitation, please visit www.kangatech.com or contact info@kangatech.com.