Concussion diagnosis and recovery in relation to collegiate athletic department classification: a LIMBIC MATARS consortium investigation.

PURPOSE: We investigated time to reach concussion diagnosis and recovery milestones in collegiate athletes relative to their schools' National Collegiate Athletic Association (NCAA) classification. METHODS: We retrospectively examined 849 (43.1% female) concussion cases from 11 NCAA institutions (Division I Power 5 [n = 4], Division I Non-Power 5 [n = 4], and Division II/III [n = 3]) from the 2015-16 to 2019-20 athletic seasons. Our primary outcome measures were days to reach specific clinical milestones following concussion. RESULTS: Median (IQR) time from injury to diagnosis was significantly longer at Division II/III institutions (1 [0-4] days) compared to Division I Power 5 (0 [0-1] days) and Division I Non-Power 5 (0 [0-1] days) institutions (p < 0.001). Likewise, Division II/III athletes (15 [11-22] days) took significantly longer to return to sport after concussion than Division I Power 5 (10 [7-16] days) and Division I Non-Power 5 (11 [7-18.5] days) athletes (p < 0.001). CONCLUSION: Division II/III athletes had delayed concussion diagnoses and return to sport timelines compared to Division I athletes. Our results suggest that differences in sports medicine resources across NCAA divisions may influence injury recognition and recovery in collegiate athletes with concussion.

The influence of ADHD on recovery from sport concussion among collegiate athletes in the United States: LIMBIC MATARS consortium investigation.

OBJECTIVE: The present study aimed to assess the potential influence of a diagnosis of ADHD on concussion recovery among collegiate athletes. DESIGN: Retrospective and cross-sectional. METHODS: Data were extracted retrospectively from medical records across LIMBIC MATARS member institutions (n = 11), representing 1,044 concussion cases among collegiate athletes. After exclusions, 406 concussions were included in our analysis (ADHD: n = 38, age = 20.2 ± 1.67 years, 18.4% female; No ADHD: n = 368, age = 19.8 ± 1.39 years, 40.1% female). Mann-Whitney U tests were used to compare days from injury to diagnosis, symptom resolution, and return to sport among athletes with and without ADHD. RESULTS: No differences were observed for days from concussion until diagnosis (z = -0.33, p = 0.74), until days to symptom resolution (z = -1.30, p = 0.19), or days until return to sport (z = -0.68, p = 0.49); among concussion cases with or without a previously reported diagnosis of ADHD. CONCLUSION: Our findings further expand the literature that suggests ADHD is not strongly associated with recovery trajectory following sport concussion in collegiate athletes. Future research should extend these findings to be inclusive of additional preexisting health conditions and moderating effects related to medication usage among diverse athlete levels.

Genetic polymorphisms associated with the risk of concussion in 1056 college athletes: a multicentre prospective cohort study.

BACKGROUND/AIM: To evaluate the association of genetic polymorphisms APOE, APOE G-219T promoter, microtubule associated protein(MAPT)/tau exon 6 Ser53Pro, MAPT/tau Hist47Tyr, IL-6572 G/C and IL-6RAsp358Ala with the risk of concussion in college athletes. METHODS: A 23-centre prospective cohort study of 1056 college athletes with genotyping was completed between August 2003 and December 2012. All athletes completed baseline medical and concussion questionnaires, and post-concussion data were collected for athletes with a documented concussion. RESULTS: The study cohort consisted of 1056 athletes of mean±SD age 19.7±1.5 years, 89.3% male, 59.4% Caucasian, 35.0% African-American, 5.6% other race. The athletes participated in American football, soccer, basketball, softball, men's wrestling and club rugby. A total of 133 (12.1% prevalence) concussions occurred during an average surveillance of 3 years per athlete. We observed a significant positive association between IL-6R CC (p=0.001) and a negative association between APOE4 (p=0.03) and the risk of concussion. Unadjusted and adjusted logistic regression analysis showed a significant association between IL-6R CC and concussion (OR 3.48; 95% CI 1.58 to 7.65; p=0.002) and between the APOE4 allele and concussion (OR 0.61; 95% CI 0.38 to 0.96; p=0.04), which persisted after adjustment for confounders. CONCLUSIONS: IL-6R CC was associated with a three times greater concussion risk and APOE4 with a 40% lower risk.

Sport concussion knowledge base, clinical practises and needs for continuing medical education: a survey of family physicians and cross-border comparison.

CONTEXT: Evolving concussion diagnosis/management tools and guidelines make Knowledge Transfer and Exchange (KTE) to practitioners challenging. OBJECTIVE: Identify sports concussion knowledge base and practise patterns in two family physician populations; explore current/preferred methods of KTE. DESIGN: A cross-sectional study. SETTING: Family physicians in Alberta, Canada (CAN) and North/South Dakota, USA. PARTICIPANTS: CAN physicians were recruited by mail: 2.5% response rate (80/3154); US physicians through a database: 20% response rate (109/545). INTERVENTION/INSTRUMENT: Online survey. MAIN AND SECONDARY OUTCOME MEASURES: Diagnosis/management strategies for concussions, and current/preferred KTE. RESULTS: Main reported aetiologies: sports/recreation (52.5% CAN); organised sports (76.5% US). Most physicians used clinical examination (93.8% CAN, 88.1% US); far fewer used the Sport Concussion Assessment Tool (SCAT1/SCAT2) and balance testing. More US physicians initially used concussion-grading scales (26.7% vs 8.8% CAN, p=0.002); computerised neurocognitive testing (19.8% vs 1.3% CAN; p<0.001) and Standardised Assessment of Concussion (SAC) (21.8% vs 7.5% CAN; p=0.008). Most prescribed physical rest (83.8% CAN, 75.5% US), while fewer recommended cognitive rest (47.5% CAN, 28.4% US; p=0.008). Return-to-play decisions were based primarily on clinical examination (89.1% US, 73.8% CAN; p=0.007); US physicians relied more on neurocognitive testing (29.7% vs 5.0% CAN; p<0.001) and recognised guidelines (63.4% vs 23.8% CAN; p<0.001). One-third of Canadian physicians received KTE from colleagues, websites and medical school training. Leading KTE preferences included Continuing Medical Education (CME) courses and online CME. CONCLUSIONS: Existing published recommendations regarding diagnosis/management of concussion are not always translated into practise, particularly the recommendation for cognitive rest; predicating enhanced, innovative CME initiatives.

Cell-based versus corticosteroid injections for knee pain in osteoarthritis: a randomized phase 3 trial.

Various types of cellular injection have become a popular and costly treatment option for patients with knee osteoarthritis despite a paucity of literature establishing relative efficacy to each other or corticosteroid injections. Here we aimed to identify the safety and efficacy of cell injections from autologous bone marrow aspirate concentrate, autologous adipose stromal vascular fraction and allogeneic human umbilical cord tissue-derived mesenchymal stromal cells, in comparison to corticosteroid injection (CSI). The study was a phase 2/3, four-arm parallel, multicenter, single-blind, randomized, controlled clinical trial with 480 patients with a diagnosis of knee osteoarthritis (Kellgren-Lawrence II-IV). Participants were randomized to the three different arms with a 3:1 distribution. Arm 1: autologous bone marrow aspirate concentrate (n = 120), CSI (n = 40); arm 2: umbilical cord tissue-derived mesenchymal stromal cells (n = 120), CSI (n = 40); arm 3: stromal vascular fraction (n = 120), CSI (n = 40). The co-primary endpoints were the visual analog scale pain score and Knee injury and Osteoarthritis Outcome Score pain score at 12 months versus baseline. Analyses of our primary endpoints, with 440 patients, revealed that at 1 year post injection, none of the three orthobiologic injections was superior to another, or to the CSI control. In addition, none of the four groups showed a significant change in magnetic resonance imaging osteoarthritis score compared to baseline. No procedure-related serious adverse events were reported during the study period. In summary, this study shows that at 1 year post injection, there was no superior orthobiologic as compared to CSI for knee osteoarthritis. ClinicalTrials.gov Identifier: NCT03818737.

Head Impact Exposure of a Youth Football Team over Eight Consecutive Seasons.

PURPOSE: This study examined HIE of middle school football players over multiple seasons. METHODS: Head impact exposure was evaluated in 103 football players (11-14 yr) who participated in a community-based youth tackle football program, up to 2 yr, with the same coaching staff over eight consecutive seasons (2012-2019). Head impact exposure was assessed using the Head Impact Telemetry System. Median of individual mean head impacts per session (HIPS) and median of individual 50th and 95th percentile head impact magnitudes were compared across seasons. RESULTS: There were 33,519 head impacts measured throughout the study. Median HIPS for all sessions decreased every year, with a significant reduction from 2012 to 2019 (11.1 vs 2.3 HIPS; P < 0.05). Median game HIPS were significantly reduced in 2019 compared with 2012-14 (5.00 vs 16.30-17.75 HIPS; P < 0.05). Median practice HIPS were reduced by 81.3%, whereas median game HIPS were reduced by 69.3%. Median 50th and 95th percentile linear and rotational acceleration were lower in 2019 compared with some earlier years but remained unchanged during games. CONCLUSIONS: Head impacts incurred by youth football players decreased substantially over eight seasons, with players in the final year sustaining approximately one fifth the HIPS as players experienced during the first year. The most prominent decline occurred in practices, although players also had much fewer head impacts in games. These results suggest that coaches' and/or players' behavior can be modified to greatly reduce the head impact burden in youth football.

The importance of salt in the athlete's diet.

Salt consists of sodium and chloride, and is important for normal physiologic function. High sweat rates in athletes result in loss of both fluids and sodium. Fluid replacement with hypotonic solutions will lead to incomplete rehydration and possible complications such as hyponatremia, decreased performance, heat cramps, or other heat-related illness. There is significant individual variation in sodium loss during activity. In some the losses can be replaced by normal dietary intake, whereas in others the losses can be dramatic and increased dietary intake is essential. There are various methods to increase sodium intake, such as increased use of table salt on foods, salty snacks, adding salt to sports drinks, and use of salt tablets. Emphasis on replacement of fluids is also important, but care must be taken to avoid overhydration. Simple measures such as recording daily pre- and postexercise body weight can aid in making fluid and sodium ingestion decisions; in some cases, a comprehensive evaluation is necessary.

Multicenter cohort study on association of genotypes with prospective sports concussion: methods, lessons learned, and recommendations.

BACKGROUND: Approximately 3.8 million sports related TBIs occur per year. Genetic variation may affect both TBI risk and post-TBI clinical outcome. Limited research has focused on genetic risk for concussion among athletes. We describe the design, methods, and baseline characteristics of this prospective cohort study designed to investigate a potential association between genetic polymorphisms of apolipoprotein E gene, APOE promoter G-219T, and Tau gene exon 6 polymorphisms (Ser53 Pro and Hist47Tyr) with: 1) the risk of prospective concussion; 2) concussion severity; and 3) postconcussion neurocognitive recovery. METHODS: The prospective cohort study included a final population of 2947 college, high school, and professional athletes. Baseline data collection included a concussion/medical history questionnaire, neuropsychological (NP) testing, and genetic sampling for the genetic polymorphisms. Data collection on new concussions experienced utilized post-concussion history/mental status form, Lovell post-concussion symptom score, Standardized Assessment of Concussion (SAC) and/or the Sports Concussion Assessment Tool (SCAT)-1/SCAT-2, and post-concussion NP testing. RESULTS: This paper is focused on discussing the important methodological considerations, organizational challenges and lessons learned in the completion of a multi-center prospective cohort study. A total of 3740 subjects enrolled, with a total of 335 concussions experienced. CONCLUSIONS: Of critical importance to the success of a study of this type is to successfully recruit committed institutions with qualified local study personnel, obtain "buy-in" from study sites, and cultivate strong working relationships with study sites. The use of approved incentives may improve study site recruitment, enhance retention, and enhance compliance with study protocols. Future publications will detail the specific findings of this study. Collaborative research is very likely needed given the nature of this study population.

Concussions in adolescent athletes.

A concussion is defined as a complex pathophysiologic process affecting the brain that is induced by traumatic biomechanical forces. Concussions are caused by a direct or indirect blow that leads to a graded set of syndromes characterized by functional rather than structural disturbances to the brain. Concussions are characterized by a wide variety of presenting symptoms, including loss of consciousness, amnesia, confusion, headache, and nausea. Concussions occur in patients participating in all levels of athletic activities, with most occurring in younger athletes. The evaluation of a patient with a concussion should include assessment of the airway, breathing, circulation, level of consciousness, orientation, memory, concentration, and neurologic function. Multiple grading scales and return to play guidelines have been published to assist the clinician in the treatment of patients with concussions. Diagnostic and treatment concerns include spinal cord injury, intracranial pathology, second impact syndrome, and long-term impairment of cognitive function. Computerized neuropsychologic testing is a new tool in the treatment of concussions. These tests measure memory, new learning, attention, and reaction time and should be used as an adjunct to other tools for clinical decision making. Published guidelines will assist in treatment decisions; however, it should be kept in mind that all concussions are unique injuries.

Head Impact Exposure and Neurologic Function of Youth Football Players.

UNLABELLED: Football players are subjected to repetitive impacts that may lead to brain injury and neurologic dysfunction. Knowledge about head impact exposure (HIE) and consequent neurologic function among youth football players is limited. PURPOSE: This study aimed to measure and characterize HIE of youth football players throughout one season and explore associations between HIE and changes in selected clinical measures of neurologic function. METHODS: Twenty-two youth football players (11-13 yr) wore helmets outfitted with a head impact telemetry (HIT) system to quantify head impact frequency, magnitude, duration, and location. Impact data were collected for each practice (27) and game (9) in a single season. Selected clinical measures of balance, oculomotor performance, reaction time, and self-reported symptoms were assessed before and after the season. RESULTS: The median individual head impacts per practice, per game, and throughout the entire season were 9, 12, and 252, respectively. Approximately 50% of all head impacts (6183) had a linear acceleration between 10g and 20g, but nearly 2% were greater than 80g. Overall, the head impact frequency distributions in this study population were similar in magnitude and location as in high school and collegiate football, but total impact frequency was lower. Individual changes in neurologic function were not associated with cumulative HIE. CONCLUSION: This study provides a novel examination of HIE and associations with short-term neurologic function in youth football and notably contributes to the limited HIE data currently available for this population. Whereas youth football players can experience remarkably similar head impact forces as high school players, cumulative subconcussive HIE throughout one youth football season may not be detrimental to short-term clinical measures of neurologic function.

Tracking postural stability of young concussion patients using dual-task interference.

OBJECTIVES: This study examined the diagnostic benefit of using dual-task interference balance testing in young concussion patients and the longitudinal changes in postural stability that occur relative to other standard clinical assessments of concussion injury. DESIGN: Longitudinal, case-control. METHODS: Eighteen patients (16.6 (1.6)y) diagnosed with a concussion provided 22 separate ratings to characterize the severity of their current concussion-related symptoms and were evaluated for postural stability at each of four clinical visits. Twenty-six injury-free adolescents (17 (2.8)y) performed balance testing on two occasions, separated by ∼1 week. RESULTS: There was a progressive decrease in self-reported symptoms from visit 1 to visit 4 (P<0.0001-0.001). A similar improvement occurred in postural stability, indicated by 95% ellipse area and velocity. However, the differences in ellipse area and velocity were significant only between visit 1 and the rest of the visits as a whole (P<0.0001-0.05). There was a significant difference between concussion patients and healthy, injury-free participants in ellipse area and velocity during visit 1. A group difference was also observed in ellipse area on visit 2, but only during the two balance tests that involved a concomitant secondary cognitive task. CONCLUSIONS: Improvements in postural stability coincide with reductions in reported symptoms, though apparent recovery of these selected measures of postural stability seemingly occurs sooner. Because of the distinguishing time course of recovery indicated by dual-task interference balance testing, this type of balance testing assessment may be particularly valuable in evaluating integrated functional impairment and recovery in young concussion patients.

Effects of youth football on selected clinical measures of neurologic function: a pilot study.

We assessed 10 youth football players (13.4 ± 0.7 y) immediately before and after their season to explore the effects of football participation on selected clinical measures of neurologic function. Postseason postural stability in a closed-eye condition was improved compared to preseason (P = .017). Neurocognitive testing with the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery revealed that reaction time was significantly faster at postseason (P = .015). There were no significant preseason versus postseason differences in verbal memory (P = .507), visual memory (P = .750), or visual motor speed (P = .087). Oculomotor performance assessed by the King-Devick test was moderately to significantly improved (P = .047-.115). A 12-week season of youth football did not impair the postural stability, neurocognitive function, or oculomotor performance measures of the players evaluated. Though encouraging, continued and more comprehensive investigations of this at-risk population are warranted.

Comparison and utility of King-Devick and ImPACT® composite scores in adolescent concussion patients.

UNLABELLED: The King-Devick (KD) oculomotor test has recently been advocated for sideline diagnosis of concussion. Although visual processing and performance are often impaired in concussion patients, the utility of KD as a concussion diagnostic tool is not validated. PURPOSE: To examine the diagnostic value of KD, by comparing KD with post-concussion symptom scale (PCSS) and ImPACT® composite scores. We hypothesized that KD would be correlated with visual motor speed/memory (VMS, VIS) and reaction time (RT), because all require cognitive visual processing. We also expected parallel changes in KD and PCSS across recovery. METHODS: Thirty-five concussed individuals (12-19 y; 18 females, 17 males) were evaluated with PCSS, ImPACT® composite and KD scores over four clinical visits (V). RESULTS: KD times improved with each visit (ΔV1-V2: 7.86±11.82; ΔV2-V3: 9.17 ± 11.07; ΔV3-V4: 5.30 ± 7.87 s) and paralleled improvements in PCSS (ΔV1-V2: 8.97 ± 20.27; ΔV2-V3: 8.69 ± 14.70; ΔV3-V4: 6.31 ± 7.71), RT (ΔV1-V2: 0.05 ± 0.21; ΔV2-V3: 0.09 ± 0.19; ΔV3-V4 0.03 ± 0.07) and VMS (ΔV1-V2: -5.27 ± 6.98; ΔV2-V3: -2.61 ± 6.48; ΔV3-V4: -2.35 ± 5.22). Longer KD times were associated with slower RT (r = 0.67; P<0.0001) and lower VMS (r = -0.70; P<0.0001), respectively. CONCLUSION: Cognitive visual performance testing using KD has utility in concussion evaluation. Validation would further establish KD as an effective ancillary tool in longitudinal concussion management and research.