Search

Objective: To assess whether National Football League (NFL) players diagnosed with a concussion have an increased risk of injury after return to football., Methods: A retrospective cohort study analysed the hazard of subsequent time-loss lower extremity (LEX) or any musculoskeletal injury among NFL players diagnosed with a concussion in 2015-2021 preseason or regular season games compared with: (1) all non-concussed players participating in the same game and (2) players with time-loss upper extremity injury. Cox proportional hazards models were adjusted for number of injuries and concussions in the prior year, player tenure and roster position. Additional models accounted for time lost from participation after concussion., Results: There was no statistical difference in the hazards of LEX injury or any musculoskeletal injury among concussed players compared with non-concussed players, though concussed players had a slightly elevated hazard of injury (LEX injury: HR=1.12, 95% CI 0.90 to 1.41; any musculoskeletal injury: HR=1.08, 95% CI: 0.89 to 1.31). When comparing to players with upper extremity injuries, the hazard of injury for concussed players was not statistically different, though HRs suggested a lower injury risk among concussed players (LEX injury: HR=0.78, 95% CI: 0.60 to 1.02; any musculoskeletal injury: HR=0.82, 95% CI: 0.65 to 1.04)., Conclusion: We found no statistical difference in the risk of subsequent injury among NFL players returning from concussion compared with non-concussed players in the same game or players returning from upper extremity injury. These results suggest deconditioning or other factors associated with lost participation time may explain subsequent injury risk in concussed players observed in some settings after return to play., Competing Interests: Competing interests: EW, AC, MH and CM are employees of IQVIA, which is in a paid consultancy with the NFL. GSS is a paid consultant to the NFL. MP is a Senior Advisor for the NFL Head Neck & Spine Committee, a member of the NFL General Medical Committee and a paid consultant to MLS. JC is the Vice Chair of the NFL Head Neck & Spine Committee and a paid consultant to the NFL. AS is a full-time employee of the NFL., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Hamstring strain injuries (HSIs) are prevalent in US National Football League (NFL) players, but there is a paucity of information regarding imaging characteristics, injury severity, and player factors associated with time missed and risk of recurrent injury., Purpose: To describe player, football activity, clinical, and imaging characteristics of NFL players with HSIs, as well as determine player characteristics, clinical examination results, and magnetic resonance imaging (MRI) findings associated with injury occurrence, severity, and missed time., Study Design: Cross-sectional study; Level of evidence, 3., Methods: A retrospective cohort of NFL players with acute HSI (n = 180) during the 2018-2019 season was identified. Injury data were collected prospectively through a league-wide electronic health record system. Three musculoskeletal radiologists graded MRI muscle injury parameters using the British Athletics Muscle Injury Classification (BAMIC) system. Player, football, clinical, and imaging characteristics were correlated with HSI incidence and severity and with missed time from sport., Results: Of the 1098 HSIs identified during the 2018-2019 season, 416 (37.9%) were randomly sampled, and 180 (43.3%) had diagnostic imaging available. Game activity, preseason period, and wide receiver and defensive secondary positions disproportionately contributed to HSI. The biceps femoris was the most commonly injured muscle (n = 132, 73.3%), followed by the semimembranosus (n = 24, 13.3%) and semitendinosus (n = 17, 9.4%) muscles. The most common injury site was the distal third of the biceps femoris and semitendinosus muscles (n = 60, 45.5% and n = 10, 58.8%, respectively) and central part of the semimembranosus muscle (n = 17, 70.8%). Nearly half of the injuries (n = 83, 46.1%) were BAMIC grade 2; 25.6% (n = 46), grade 3; and 17.8% (n = 32), grade 4. MRI showed sciatic nerve abnormality in 30.6% (n = 55) of all HSIs and 81.3% (n = 26) of complete tendon injuries. BAMIC grade correlated with both median days and games missed. Combined biceps femoris and semitendinosus injuries resulted in the highest median days missed (27 days)., Conclusion: Among NFL players with acute HSIs, the most common injury was a moderate-severity injury of the distal biceps femoris. BAMIC grade was associated with missed time., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: M.A.D. has received support for education from Great Lakes Orthopedics, Smith & Nephew, and Arthrex; grant from Arthrex; and hospitality payments from Stryker and Encore Medical. V.K. has received consulting fees from Hyalex Orthopaedics. A.B. has received royalties from Arthrex; consulting fees from Arthrex; and speaking fees from Synthes GmbH. S.A.R. is an associate editor for AJSM and has received consulting fees from Teladoc, DJO, and Novartis Pharmaceuticals Corporation; speaking fees from Terumo BCT and Smith & Nephew; and holds stock or stock options in Ortho RTI. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Transient traumatic neuropraxia of either the brachial plexus or cervical nerve root(s) is commonly described as a "stinger" or "burner" by the athlete. Stingers in American Football commonly occur acutely as isolated injuries; however, concomitant injuries, including cervical spine pathologies, have also been reported., Hypothesis: Among National Football League (NFL) athletes, the incidence rate of stingers is higher during the regular season than during the preseason and among positions with high velocity impacts such as running backs, linebackers, defensive backs, and receivers., Study Design: Retrospective epidemiology study., Level of Evidence: Level 4., Methods: Aggregation of all in-game injuries with a clinical impression of "neck brachial plexus stretch" or "neck brachial plexus compression" entered into the NFL injury surveillance database through the centralized league-wide electronic medical record system over 5 years (2015-2019 seasons). Incidence rates per player-play were calculated and reported., Results: A total of 691 in-game stingers occurred during the study period, with a mean of 138.2 per year. Average single-season injury risk for incident stinger was 3.74% (95% CI, 3.46%-4.05%). The incidence rate was higher during regular season games than during preseason games (12.26 per 100,000 player-plays [11.30-13.31] vs 8.87 [7.31-10.76], P < 0.01, respectively). The highest reported stinger incidence rates were among running backs and linebackers (both >15 per 100,000 player-plays). Among stingers, 76.41% did not miss time. Of those that resulted in time lost from football activities, mean time missed due to injury was 4.79 days (range, 3.17-6.41 days). Concomitant injuries were relatively low (7.09%)., Conclusion: In-game stinger incidence was stable across the study period and occurred most frequently in running backs and linebackers. Stingers were more common during the regular season, and most players did not miss time. Concomitant injuries were relatively rare., Clinical Relevance: An improved understanding of the expected time loss due to stinger and concomitant injuries may provide insight for medical personnel in managing these injuries., Competing Interests: The following authors declared potential conflicts of interest: J.D.L. has received consulting fees from DePuy Mitek and speaking payments or honoraria from Arthrex and Smith & Nephew. G.S.S. has received consulting fees from the National Football League. G.D.M. has received royalties from Human Kinetics and Wolters Kluwer and holds patents in biofeedback technologies. K.H. has received consulting fees from Arthrex.

Background: Lower extremity (LEX) strains, including hamstring, quadriceps, adductor, and calf strains, are among the most common injuries in sports. These injuries lead to high burden, resulting in significant missed participation time., Purpose: To describe the incidence of LEX strains in professional American football., Study Design: Descriptive epidemiology study., Methods: This study included all players who played in ≥1 National Football League (NFL) game or sustained a LEX strain during participation in the 2015-2019 seasons. LEX strain frequency was calculated by setting (game, practice, conditioning), timing in season (offseason, preseason, regular season, postseason), and roster position. Game incidence rates were calculated for season, roster position, and play type. LEX strains were identified in the standardized leaguewide electronic health record (n = 32 teams)., Results: Across 5 years, 5780 LEX strains were reported among 2769 players (1-year risk, 26.7%; 95% CI, 26.0%-27.3%); 69% (n = 4015) resulted in time loss. Among all LEX strains, 54.7% were hamstring (n = 3163), 24.1% adductor (n = 1393), 12.6% calf (n = 728), 8.3% quadriceps (n = 477), and 0.3% multiple muscle groups (n = 19). Most were reported during preseason practices (n = 1076; 27%) and regular season games (n = 1060; 26%). The 2-week period of training camp practices comprised 19% of all time-loss strains. Among game injuries, preseason games had the highest rate of LEX strain (2.9/10,000 player-plays; 95% CI, 2.6-3.2). Defensive secondary players accounted for the highest proportion of time-loss LEX strains (27%; n = 1082). In games, punt plays had nearly twice the injury rate of kickoff plays (14.9/1000 plays [95% CI, 13.1-17.0] vs 7.5/1000 plays [95% CI, 6.2-8.9], respectively) and >3 times the rate of pass plays (4.3/1000 plays; 95% CI, 4.0-4.7) and run plays (2.6/1000 plays; 95% CI, 2.3-2.9). In aggregate, LEX strains led to an estimated 16,748 participation days missed each year and a median 12 days missed per injury., Conclusion: LEX strains affected 1 in 4 NFL players each year, resulting in a high burden of injury in terms of time lost from practice and competition. Safe return to the NFL season during training camp and reduction of injuries during regular season games are key focuses for future injury reduction.

Objective: Quantify days missed, games missed, injury burden, and time to return to full participation (RTFP) among National Football League (NFL) players who sustained a concussion., Design: Retrospective cohort study., Setting: 2015 through 2020 NFL seasons., Participants: National Football League players diagnosed with a concussion from 2015 to 2020., Interventions: National Football League-mandated graduated RTFP protocol., Main Outcome Measures: Days missed, games missed, burden, and time to RTFP, overall and by position., Results: An annual average of 3639 player-days of participation and 255 games were missed across NFL because of concussion. Concussed players missed a median of 9 days (mean = 15.0), a relatively stable metric over 6 years, with slight variation by position. Offensive linemen, tight ends, running backs, and linebackers missed the most days per concussion; defensive secondary, offensive linemen, and wide receivers sustained the highest injury burden. Postconcussion, 59% of players missed one or more scheduled games. Among players concussed in a Sunday game, 38% played in a Sunday game one week later., Conclusions: The 9-day median time missed post-concussion may be related to emphasis on graduated phase-based concussion management. No concussed player returned to competition on the day of injury, and less than 40% participated in games the following week. Further work is needed to better understand characteristics of concussions that take longer to return and movement through stages of return., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Sport-related concussion (SRC) prevention and management is a focus of the National Football League (NFL). While most prior reports evaluated sport-related concussion incidence, few have studied same-year repeat concussions. This study aimed to evaluate the frequency of same-year repeat concussions in the NFL., Methods: A retrospective, observational cohort study of same-year repeat concussions in the NFL from 2015 to 2019 was performed. The NFL's electronic health record was reviewed for players sustaining concussions and same-year repeat concussions. Wilcoxon rank sum tests were used to calculate same-year repeat concussion rates, and risk ratios and 95% confidence intervals were estimated using log-binomial regression., Results: From 2015 to 2019, the risk of sustaining a same-year repeat concussion in the NFL was 0.38%-0.69% per season. Among players who sustained a concussion, the risk of a same-year repeat concussion was 5.3%-8.3%, which did not differ significantly from the risk of sustaining a single concussion (6.2%-8.3%). There was a median of 38 participation days between initial and same-year repeat concussion. Players missed more time from same-year repeat concussions (median 12 days) compared with both single (median 9 days; P < 0.0001) and initial (median 9.5 days; P = 0.002) concussions., Conclusions: The risk of a repeat concussion was similar to the risk of sustaining a single concussion among NFL players. More time was missed following a same-year repeat concussion compared with single or initial concussions. Further research is needed to maximize player safety and minimize same-year repeat concussions., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Anterior cruciate ligament (ACL) tears are common in contact athletics and have a significant effect on the athletic performance and well-being of affected players. The prevalence, timing, and characteristics of ACL tears in National Football League (NFL) athletes are lacking., Purpose: To define the epidemiology of ACL tears among NFL athletes., Study Design: Descriptive epidemiology study., Methods: This retrospective study includes all ACL injuries entered into the NFL injury database through the centralized leaguewide electronic health record system for the 2015-2019 seasons., Results: A total of 314 ACL injuries occurred during the 5-year study period, with a mean of 62 per year. The overall 1-season injury risk of an NFL player sustaining an ACL injury was 1.9% (95% CI, 1.7%-2.1%). Most ACL injuries occurred during games (n = 199), with a higher rate observed in the preseason games as compared with the regular season games (6.1 vs 2.7 per 10,000 player-plays; P < .01). NFL players with ≤3 of experience had a higher preseason injury rate (9.57 ACL tears per 1000 player-seasons) than those with ≥4 years of experience (5.12 ACL tears per 1000 player-seasons; P < .01). NFL athletes playing on special teams had the highest rate of ACL injuries (7.6 per 10,000 player-plays) in comparison with all other player positions., Conclusion: ACL injury incidence was fairly consistent across all years studied and occurred more frequently in players with ≤3 years of NFL experience. Tears were more common during games, special teams play, and the preseason.

Background: The inherent risk of any time loss from physical injury in football has been extensively discussed, with many such injuries having a profound effect on the lives of National Collegiate Athletic Association (NCAA) football players. However, the incidence of fractures in collegiate football has not been well established., Purpose: To examine the epidemiology of fractures in NCAA football., Study Design: Descriptive epidemiology study., Methods: Fracture data reported in college football during the 2004-2005 to 2013-2014 academic years were analyzed from the NCAA Injury Surveillance Program (NCAA-ISP). Fracture rates per 1000 athlete-exposures, surgery and time loss distributions, injury rate ratios, injury proportion ratios (IPRs), and 95% CIs were reported., Results: Overall, 986 fractures were reported. The rate of competition fractures was larger than the rate of practice fractures (1.80 vs 0.17 per 1000 athlete-exposures; injury rate ratio = 10.56; 95% CI, 9.32-11.96). Fractures of the hand/fingers represented 34.6% of all injuries, while fibula fractures (17.2%) were also common. A majority (62.5%) of all fractures resulted in time loss >21 days. Altogether, 34.4% of all fractures required surgery, and 6.3% were recurrent. The proportion of fractures resulting in time loss >21 days was higher for fractures requiring surgery than fractures not requiring surgery (85.0% vs 50.7%; IPR = 1.68; 95% CI, 1.53-1.83). The proportion of recurrent and nonrecurrent fractures requiring surgery did not differ (35.5% vs 34.3%; IPR = 1.03; 95% CI, 0.73-1.46); however, recurrent fractures were more likely to require surgery than nonrecurrent fractures when restricted to the hand/fingers (66.7% vs 27.2%; IPR = 2.45; 95% CI, 1.36-4.44)., Conclusion: Fractures in collegiate football were sustained at a higher rate in competition than practice and frequently required extended time lost from participation, particularly among those requiring surgery. Prevention strategies are warranted to reduce incidence and severity of fractures.

Background: Anterior cruciate ligament (ACL) tears are a high-frequency injury requiring a lengthy recovery in professional American football players. Concomitant pathology associated with ACL tears as identified on magnetic resonance imaging (MRI) is not well understood in these athletes. Purpose: To describe the MRI findings of concomitant injuries associated with ACL tears among athletes in the National Football League (NFL). Study Design: Cross-sectional study; Level of evidence, 3. Methods: Of 314 ACL injuries in NFL athletes from 2015 through 2019, 191 complete MRI scans from the time of primary ACL injury were identified and reviewed by 2 fellowship-trained musculoskeletal radiologists. Data were collected on ACL tear type and location, as well as presence and location of bone bruises, meniscal tears, articular cartilage pathology, and concomitant ligament pathology. Mechanism data from video review were linked with imaging data to assess association between injury mechanism (contact vs noncontact) and presence of concomitant pathology. Results: Bone bruises were evident in 94.8% of ACL tears in this cohort, most often in the lateral tibial plateau (81%). Meniscal, additional ligamentous, and/or cartilage injury was present in 89% of these knees. Meniscal tears were present in 70% of knees, lateral (59%) more than medial (41%). Additional ligamentous injury was present in 71% of all MRI scans, more often a grade 1/2 sprain (67%) rather than a grade 3 tear (33%), and most often involving the medial collateral ligament (MCL) (57%) and least often the posterior cruciate ligament (10%). Chondral damage was evident in 49% of all MRI scans, with ≥1 full-thickness defect in 25% of all MRI scans, most often lateral. Most (79%) ACL tears did not involve direct contact to the injured lower extremity. Direct contact injuries (21%) were more likely to have a concomitant MCL tear and/or medial patellofemoral ligament injury and less likely to have a medial meniscal tear. Conclusion: ACL tears were rarely isolated injuries in this cohort of professional American football athletes. Bone bruises were almost always present, and additional meniscal, ligamentous, and chondral injuries were also common. MRI findings varied by injury mechanism. [ABSTRACT FROM AUTHOR]

Background: There is a paucity of literature regarding injury incidence, mechanism, and return to play in National Football League (NFL) players who have sustained traumatic posterior hip instability. Purpose: To describe the incidence of traumatic posterior hip instability and the rate of return to play in NFL players across 18 seasons. Study Design: Descriptive epidemiology study. Methods: We retrospectively assessed all traumatic posterior hip dislocations/subluxations that occurred during football-related activities in the NFL seasons from 2000 through 2017. Player demographics and injury data (injury mechanism, season of injury, treatment, days missed, and return to play time) were collected from all 32 NFL teams prospectively through a leaguewide electronic health record system. Descriptive statistics are presented. Results: Across the 18 NFL seasons, 16 posterior hip instability injuries in 14 players were reported, with a maximum incidence of 4 (25%) in 2013. Posterior hip instability was predominantly sustained by offensive players (64.3%), with tight ends being the most affected (31.3%). Half of the injuries occurred during the regular season, 43.8% in the preseason, and 6.2% in the offseason. Of all injuries, 37.5% were noncontact, while 56.3% involved contact (direct or indirect), and 6.2% were of unknown mechanism. Among noncontact injuries, 66.7% occurred during cutting and change of direction while sprinting. The time of return to full participation was documented for 11 of the 16 reported injuries (68.8%); among them, the mean time loss was 136.7 ± 83.8 days—143.3 ± 99.6 days if the player underwent surgery (n = 4) and 116.7 ± 76.2 days missed by players without surgery (n = 6)—the treatment modality was unknown in 1 player. Conclusion: Although the incidence of traumatic posterior hip instability during the study period was low, all injured athletes missed time from football activities and competitions. Injuries that required surgery led to more missed time than those that did not. Ongoing research to understand risk factors and mechanisms of this injury, in conjunction with improvements to prevention and rehabilitation protocols, is necessary to ensure the safety of professional American football players. [ABSTRACT FROM AUTHOR]

Background: The factors associated with anterior cruciate ligament (ACL) injury mechanism in professional American football players are not well-understood. Hypothesis: It was hypothesized that football-related and player-specific factors, such as position and body mass index (BMI), are associated with ACL injury mechanism in these athletes. Study Design: Descriptive epidemiology study. Methods: Videos of ACL tears occurring in National Football League (NFL) games over 6 consecutive seasons from 2014 to 2019 were reviewed by 2 orthopaedic surgeons who specialize in sports medicine. For each injury, the role of contact (direct contact [contact to the injured knee/lower extremity], indirect contact [contact not involving the injured knee/lower extremity], or no contact) as well as playing situation and lower extremity position were recorded. Additional player characteristics, timing of injury, and surface information were obtained from NFL game-day and injury database statistics. Results: Of the 140 ACL tears, a minority occurred via direct contact to the injured lower extremity (30%), although this varied by position. Just over two-thirds (70%) of ACL tears in offensive linemen occurred via direct contact to the injured lower extremity, while wide receivers had no direct contact ACL tears. Elevated BMI was associated with a greater likelihood of ACL tears occurring via direct contact (53% in players with BMI ≥35 kg/m2 vs 24% in players with BMI <35 kg/m2; P = <.01). Rookies had the lowest percentage of direct contact ACL tears (18%; P =.22). ACL tears that occurred during the middle 8 weeks of the regular season resulted more often from direct contact (38%; P =.06). ACL tears that occurred in the third quarter were the most likely to occur via direct contact (44%), while those that occurred in the fourth quarter were the least likely to occur via direct contact (13%; P <.01). Conclusion: Although most NFL players sustained ACL tears via a noncontact mechanism (ie, through indirect or no contact), players with an elevated BMI, especially on the offensive line, were more likely to injure their ACL through direct contact. Position-dependent variance in injury mechanism may help guide injury prevention efforts in these athletes. [ABSTRACT FROM AUTHOR]

Objectives: Shoulder instability is a common injury among contact- and collision-sport athletes that encompasses a spectrum of glenohumeral pathology ranging from subluxation to dislocation. While glenohumeral dislocation frequently leads to removal from play, athletes are often able to play through glenohumeral subluxation. Previous research on glenohumeral instability among athletes has largely focused on missed-time injuries only, which has likely disproportionately excluded subluxation injuries and underestimated the overall incidence of shoulder instability. The objective of this study is to describe the epidemiology of shoulder instability injuries not resulting in missed time among professional athletes in the National Football League (NFL) during the 2015 through 2019 seasons. Methods: The NFL's Electronic Medical Record was retrospectively reviewed to identify shoulder instability injuries that did not result in missed time during the 2015 through 2019 seasons. For each injury, player age, player position, shoulder laterality, instability type, instability direction, injury timing, injury setting, and injury mechanism were recorded. For injuries that occurred during games, incidence rates were calculated based on timing during the season as well as player position. The influence of player position on instability direction was also investigated. Results: During the 2015 through 2019 seasons, 546 shoulder instability injuries were documented in the NFL's Electronic Medical Record. Of these, 162 (29.7%) did not result in missed time beyond the date of injury. The majority of non-missed-time injuries were subluxations (97.4%), occurred during games (70.7%), and resulted from a contact mechanism (91.2%). The overall incidence rate of game-related instability was 1.6 injuries per 100,000 player-plays and was highest during the postseason (3.5 per 100,000 player-plays). With respect to player position, the greatest number of non-missed-time instability injuries occurred in defensive secondary (28.4%) and offensive linemen (19.8%), while kickers/punters and defensive secondary had the highest game incidence rates (5.5 and 2.1 per 100,000 player-plays, respectively). In terms of direction, 54.3% of instability events were posterior, 31.9% anterior, 8.5% multidirectional, and 5.3% inferior. Instability events were most often anterior among linebackers and wide receivers (50% and 100%, respectively), while posterior instability was most common for defensive linemen (66.7%), defensive secondary (58.6%), quarterbacks (100.0%), running backs (55.6%), and tight ends (75.0%). Conclusions: Shoulder instability injuries that do not result in missed time beyond the date of injury are much more common among collision-sport athletes than previously thought, accounting for approximately 30% of all instability events in the NFL. The majority of these injuries are posterior subluxations, though instability direction appears to vary by player position. This study highlights the diverse nature of shoulder instability injuries and underscores the need for increased surveillance among collision-sport athletes, as even subluxations can result in significant damage to the capsulolabral complex. TABLE 1. Non-missed-time shoulder instability injuries by year from 2015 through 2019a. TABLE 2. Incidence of game-related non-missed-time shoulder instability injuries by season from 2015 through 2019. TABLE 3. Incidence of game-related non-missed-time shoulder instability injuries by player roster positiona from 2015 through 2019b. Figure 1. Distribution of non-missed-time shoulder instability direction by player roster position from 2015 through 2019. [ABSTRACT FROM AUTHOR]