2024 Kappa Delta Ann Doner Vaughan Award Nonsurgical Treatment of Symptomatic, Atraumatic Full-Thickness Rotator Cuff Tears-a Prospective Multicenter Cohort Study With 10-Year Follow-Up.

The Multicenter Orthopaedic Outcomes Network Shoulder Group conducted a prospective cohort study of 452 patients with symptomatic atraumatic rotator cuff tears treated with a physical therapy program to determine the predictors of failure of nonsurgical treatment, to provide insight into indications for surgery. After 10 years, we found the following: (1) Physical therapy was effective for over 70% of patients. (2) PROMs showed statistical and clinical improvement after 12 weeks of therapy and did not decline over 10 years. (3) Cuff tear severity did not correlate with pain, duration of symptoms, or activity level. (4) Of those who had surgery, 56.7% had surgery in the first 6 months while 43.3% had surgery between 6 months and 10 years. (5) Early surgery was primarily driven by low patient expectations regarding the effectiveness of therapy. (6) Later surgery predictors included workers' compensation status, activity level, and patient expectations. (7) Only 1 patient had a reverse arthroplasty (0.2% of the cohort). These data suggest that physical therapy is an effective and durable treatment of atraumatic symptomatic rotator cuff tears and most patients successfully treated with physical therapy do not exhibit a decline in patient-reported outcomes over time. Reverse arthroplasty after nonsurgical treatment is exceptionally rare.

Influence of pre-existing conditions and concussion history on post-concussion symptom severity and recovery time in collegiate athletes.

Mental health conditions and concussion history reported by a collegiate athlete may contribute to prolonged recovery and symptom severity after concussion. This work examined the potential associations among concussion history, pre-existing conditions, and sex relative to initial symptom severity and recovery duration following sport-related concussion (SRC) in a cohort of Division 1 NCAA athletes. This prospective cohort study analyzed symptom severity, recovery and return-to-play times reported post-SRC using data collected as part of the Pac-12 CARE Affiliated Program and Health Analytics Program. Health history questionnaires which included self-reported history of pre-existing conditions were completed at baseline. When consented athletes were diagnosed with a concussion, daily post-concussion symptom scores were evaluated until an athlete was clinically determined to be asymptomatic. Generalized linear and Cox proportional hazards models were used to determine associations between pre-existing conditions and recovery and return-to-play times. 92 concussions met inclusion criteria. Notable differences in initial symptom severity existed between females and males who had mood disorders ([Cohen's d] = 0.51) and ADHD (d = 0.93). The number of previous concussions was a strong predictor of athletes reporting pre-existing mood disorders, depression, anxiety, and ADHD (p = 0.008-0.04). Females with ≥2 previous concussions required more days to return-to-play than males (d = 0.31-0.72). Weekly recovery and return-to-play probabilities substantially differed between athletes that did or did not have learning disorders (HRRecovery = 0.32, HRRTP = 0.22, d = 1.96-2.30) and ADHD (HRRecovery = 3.38, HRRTP = 2.74, d = 1.71-4.14). Although no association existed between concussion history and acute symptom severity, collegiate athletes with a history of concussion had higher probabilities of reporting depression, mood disorders, anxiety, and ADHD. Having ADHD or learning disorders likely strongly affects time to recovery and return-to-play for collegiate athletes.

The Predictors of Surgery for Symptomatic, Atraumatic Full-Thickness Rotator Cuff Tears Change Over Time: Ten-Year Outcomes of the MOON Shoulder Prospective Cohort.

BACKGROUND: A prospective cohort study was conducted to assess the predictors of failure of nonoperative treatment, defined as the patient undergoing surgery for symptomatic, atraumatic full-thickness rotator cuff tears. We present the 10-year follow-up data of this population to determine if predictors for surgery change over time, and secondarily we report the outcomes of the cohort. METHODS: At the time of enrollment, demographic, symptom, rotator cuff anatomy, and patient-reported outcome data were collected in patients with symptomatic, atraumatic full-thickness rotator cuff tears. Patients underwent a standard physical therapy protocol for 6 to 12 weeks. Patient data were then collected at 1, 2, 5, 7, and 10 years. Failure of nonoperative treatment was defined as the patient electing to undergo surgery. RESULTS: Of the 452 patients in the original cohort, 20 patients (5%) withdrew from the study, 37 (9%) died before 10 years, and 40 (9%) were otherwise lost to follow-up. A total of 115 patients (27.0%) underwent a surgical procedure at some point during the 10-year follow-up period. Of these patients, 56.5% underwent surgery within 6 months of enrollment and 43.5%, between 6 months and 10 years. Low patient expectations regarding the efficacy of physical therapy were found to be a predictor of early surgery. Workers' Compensation status and activity level were more important predictors of later surgery. Patient-reported outcome measures all improved following physical therapy. For patients who did not undergo a surgical procedure, patient-reported outcome measures did not decline over the 10-year follow-up period. CONCLUSIONS: Low patient expectations regarding the efficacy of physical therapy were found to be a predictor of early surgery, whereas Workers' Compensation status and activity level were predictors of later surgery. Physical therapy was successful in >70% of patients with symptomatic, atraumatic full-thickness rotator cuff tears at 10 years. Outcome measures improved with physical therapy and did not decline over the 10-year follow-up period. LEVEL OF EVIDENCE: Prognostic Level I . See Instructions for Authors for a complete description of levels of evidence.

Obesity is associated with muscle atrophy in rotator cuff tear.

Objective: The primary goal of this study is to evaluate the relationship between Body Mass Index (BMI) and muscle atrophy in individuals with rotator cuff tears. Methods: This study consists of patients with rotator cuff tears identified by MRI from two independent cohorts, the Rotator Cuff Outcomes Workgroup (ROW) and the Multicenter Orthopaedic Outcomes Network (MOON). Presence of atrophy (yes/no) and severity of atrophy (as an ordinal variable) were assessed on MRI by expert physicians. We used multivariable regression models to evaluate the relationship between BMI and muscle atrophy while adjusting for age and sex in each study, conducted sensitivity analyses for full-thickness tear and combined results using inverse variance-weighted meta-analysis. Results: A total of 539 patients (MOON=395, ROW=144) from the combined cohorts had MRI data available on muscle atrophy. Among these patients, 246 (46%) had atrophy of at least one of the muscles of the rotator cuff and 282 (52%) had full-thickness tears. In meta-analysis across both cohorts, each 5 kg/m2 increase in BMI was associated with a 21% (aOR=1.21, 95% CI=1.02, 1.43) increased odds of having muscle atrophy among individuals with any tear size, and 36% (aOR=1.36, 95% CI=1.01-1.81) increased odds among individuals with full-thickness tear. Conclusions: Higher BMI was associated with significantly higher odds of muscle atrophy in patiens with rotator cuff tears. More study is needed to unders1tand why and how this relationship exists, as well as whether interventions to reduce BMI may help improve outcomes for these patients. Level of Evidence: III.

Diagnosis of Sports-Related Concussion Using Symptom Report or Standardized Assessment of Concussion.

Importance: The Sports Concussion Assessment Tool-5 (SCAT5) has been recommended for concussion evaluation and utilizes both a subjective reported symptom grading scale and objective measures of concussion including a cognitive evaluation: the Standardized Assessment of Concussion (SAC). The SAC includes testing for orientation, immediate memory, concentration, and delayed recall; a 10-word list is used to assess immediate memory and delayed recall. Objective: To determine the diagnostic accuracy of components of the SCAT5 and to provide a framework for clinical interpretation. Design, Setting, and Participants: This prospective case-control study of National Collegiate Athletic Association Division I athletes from any sport was conducted from July 2020 to December 2022 at 4 universities. Athletes completed baseline SCAT5 testing using the 10-word list. When an athlete presented acutely with suspected concussion (sideline or within 2 days), the tests were repeated. If a concussion was diagnosed, a control athlete underwent the same tests. Controls were identified and matched on comorbid conditions, sex and gender, sport, season, and baseline scores. Data analysis was conducted from August to October 2023. Main Outcomes and Measures: The primary outcomes were area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive and negative predictive value, and test-retest reliability of the symptom score; symptom severity score; the total SAC score; and the orientation, immediate memory, concentration, and delayed memory subcomponent scores on the SCAT5 compared with clinical diagnosis of concussion. Results: Baseline and postinjury data were collected on 92 athletes with concussion and 92 matched control athletes (96 men [52%] and 88 women [48%]; 110 who played a sport other than football [59%]). Diagnostic utility was considered excellent for symptom score (AUC, 0.93; 95% CI, 0.89-0.96) and symptom severity score (AUC, 0.94; 95% CI, 0.90-0.97). An increase of 2 points on the symptom score was associated with a sensitivity of 86% (95% CI, 78%-92%), specificity of 80% (95% CI, 70%-87I%), and positive predictive value of 81% (95% CI, 72%-88%). The total SAC score had poor to fair diagnostic utility (AUC, 0.70; 95% CI, 0.63-0.77); however, 41 athletes with concussion (45%) had a total SAC score at or above their baseline score (ie, within normal limits). The diagnostic utility was poor to fair for immediate memory (AUC, 0.68, 95%CI, 0.61-0.75) and delayed recall (AUC, 0.69; 95% CI, 0.62-0.77) and not useful for orientation (AUC, 0.49; 95% CI, 0.43-0.56) and concentration (AUC, 0.52 95% CI, 0.44-0.61). Test-retest reliability was fair for total SAC and poor for immediate memory and delayed recall, orientation, and concentration. Conclusions and Relevance: In this case-control study of the diagnostic accuracy of reported symptoms and the SAC, reported symptoms were the most accurate indicator of concussion while the 10-word SAC had limited sensitivity. These findings suggest that understanding the properties of the SAC is important when making the diagnosis of concussion.

Recovery duration and concussion severity in sport- and non-sport-related concussion among Pac-12 collegiate athletes: a retrospective cohort study.

OBJECTIVES: To examine non-sport- and sport-related concussion severity, clinical care frequency and delayed reporting in relation to recovery duration among collegiate athletes. DESIGN: Retrospective cohort study. SETTING: Pac-12 varsity collegiate athletes. PARTICIPANTS: 461 collegiate male and female athletes PRIMARY AND SECONDARY OUTCOME MEASURES: The incidence of sport-related concussion (SRC) and non-sport-related concussion (NRC) were collected as well as times to recovery and return-to-play (RTP), symptom score and symptom severity and reported a loss of consciousness (LOC), retrograde amnesia (RGA) and post-traumatic amnesia (PTA) following concussion incidence. RESULTS: Among 461 concussions, 388 (84%) occurred within sport and 73 (16%) occurred outside of sport. NRC, on average, required 3.5 more days to become asymptomatic (HR: 0.73, 95%confidence interval: 0.56 to 0.96, p=0.02) and 7 more days to RTP (HR: 0.64, 95% confidence interval: 0.49 to 0.85, p<0.01) compared with SRC. NRC were associated with an increase of 1.83 (p=0.07) symptoms reported at the time of diagnosis, an increase of 6.95 (p=0.06) in symptom severity and a higher prevalence of reported LOC (22% NRC vs. 3% SRC, p<0.001), PTA (15% NRC vs. 5% SRC, p<0.01) and RGA (10% NRC vs. 4% SRC, p=0.06), compared with SRC. There was no significant difference in clinical care (p=0.28) or immediate reporting (p=0.35) between NRC and SRC. CONCLUSION: NRC were associated with greater severity and longer recovery duration when compared with SRC in a cohort of collegiate athletes.

Nominal Differences in Acute Symptom Presentation and Recovery Duration of Sport-Related Concussion Between Male and Female Collegiate Athletes in the PAC-12.

BACKGROUND: Sport-related concussion (SRC) is a heterogenous injury that often presents with varied symptoms and impairment. Recently, research has focused on identifying subtypes, or clinical profiles of concussion to be used in assessing and treating athletes with SRC. The purpose of this study was to investigate sex differences in clinical profiles, recovery duration, and initial symptom severity after SRC in a cohort of collegiate athletes in the Pacific-12 Conference (Pac-12). METHODS: This prospective cohort study examined post-SRC symptoms, recovery, and return-to-play times using data from the Pac-12 CARE Affiliated Program and Pac-12 Health Analytics Program. Clinical profiles reported by student-athletes were defined by the number (> 50%) of specific symptoms frequently reported for each profile. Generalized linear mixed models were used to examine associations among sex, clinical profiles, time-to-recovery, and return-to-play times. RESULTS: 479 concussion incidents met inclusion criteria. The probabilities of initial presentation of each clinical profile, initial injury severity scores, and recovery times within a profile did not differ between sexes (p = 0.33-0.98). However, both males and females had > 0.75 probabilities of exhibiting cognitive and ocular profiles. Initial injury severity score was a strong nonlinear predictor of initial number of clinical profiles (p < 0.0001), which did not differ between sexes. The number of clinical profiles was also a nonlinear predictor of time-to-recovery (p = 0.03) and return-to-play times (p < 0.0001). CONCLUSIONS: Initial symptom severity was strongly predictive of the number of acute clinical profiles experienced post-SRC. As the number of clinical profiles increased, time-to-recovery and time to return-to-play also increased. Factors other than sex may be better associated with acute symptom presentation post-concussion as no sex differences were found in reported clinical profiles or recovery. Understanding the number and type of clinical profiles experienced post-SRC may help inform concussion diagnostics and management.

Effect of the 2018 NCAA Kickoff Rule Change on Concussion Rates in Collegiate Football: Results From a Division 1 Conference.

Background: Kickoff plays in American football are associated with an increased risk of concussion compared with other play types. In 2018, the National Collegiate Athletic Association (NCAA) Football Rules Committee altered the kickoff rules so a fair catch inside the 25-yard line results in a touchback, with the ensuing drive starting on the 25-yard line. The intention was to decrease the number of kickoff returns with a corresponding decrease in the rate of concussions on kickoff plays. Purpose: To determine whether the 2018 rule changes had the intended effects in an NCAA Division 1 Conference. Study Design: Cohort study; Level of evidence, 3. Methods: The study population included football athletes in the NCAA Pacific-12 (Pac-12) Conference. Data on the total number of plays, punts, kickoffs, touchbacks, and fair catches were obtained for all in-conference games from the 2016 to 2021 seasons. The number of game concussions and the play type were provided by each conference institution. Incidence of concussions occurring during kickoff plays before (2016-2017) and after (2018-2021) the rule change were compared with a difference-in-difference analysis using Poisson general linear models. Results: There were 242 concussions in 108,774 total plays in the study period, with an overall concussion rate of 2.2 per 1000 plays. The percentage of touchbacks increased significantly from 45% to 51% (P < .001) and the percentage of fair catches increased from 1% to 7% (P < .001) from before to after the rule change. Kickoffs accounted for 6% of plays both before and after the rule change and 11% of concussions before and 14% after the change. The mean annual concussion rate (per 1000 plays) on kickoffs was 3.42 before and 5.31 after the rule change (rate difference: 1.89; 95% confidence interval, -1.22 to 5.01). Conclusion: Touchbacks and fair catches increased after the kickoff rule change, but there was not a corresponding decrease in concussions during kickoff plays as anticipated. Concussions occurring during other football plays remained stable.

The Collapsed Athlete: General Principles.

The collapsed athlete encompasses multiple critical and noncritical pathologic conditions, management of which highly depends on the elements of presentation of an athlete, the environment in which the athlete presents, and the key history elements leading to the collapse. Early identification of an unresponsive/pulseless athlete with basic life support/CPR, AED use, and EMS activation is key, with the addition of early hemorrhage control in acute traumatic injuries. The initiation of a focused history and physical examination is critical to rule out life-threatening causes of collapse and to guide initial management and disposition.

Multicentre evaluation of anxiety and mood among collegiate student athletes with concussion.

Objectives: Mental health problems are a premorbid and postinjury concern among college student athletes. Clinical phenotypes of anxiety and mood disruption are prevalent following mild traumatic brain injury, including concussion, a common sports injury. This work examined whether concussed student athletes with a history of mental health problems and higher symptoms of anxiety and mood disruption at baseline were more likely to have higher postinjury reports of mood and anxiety as well as prolonged resolution of postconcussive symptoms to near-baseline measures. Methods: This was a retrospective cohort study of a multi-institutional database of standardised baseline and postinjury assessments among college student athletes. Anxiety/mood evaluation data among varsity college athletes from four institutions over 1 year were measured and compared at baseline and postconcussion recovery using descriptive statistics and multilevel/mixed-effects analysis. Results: Data from 2248 student athletes were analysed, with 40.6% reporting at least one symptom of anxiety and/or mood disruption at baseline. Of the 150 distinct concussions, 94.7% reported symptoms of anxiety/mood disruption during recovery (recovery time=0-96 days). Higher anxiety/mood scores at baseline were significantly associated with higher scores following concussion (p<0.001). Recovery trajectories of anxiety/mood scores showed different patterns by sex and prolonged recovery. Conclusion: Symptoms of anxiety and mood disruption are common at baseline among college student athletes. These students are at higher risk for symptomatology following injury, representing a screening cohort that may benefit from early counselling. Almost all student athletes will experience symptoms of anxiety and/or mood disruption following concussion.

Iron Status and Homeostasis Across 2 Competitive Seasons in NCAA Division I Collegiate Cross-Country Runners Residing at Low Altitude.

PURPOSE: Inflammatory cytokines including interleukin-6 can upregulate hepcidin and decrease iron absorption. Endurance exercise is associated with transient increases in cytokines, which may alter the risk of iron deficiency (ID). This study examined whether chronic elevations in basal levels of cytokines and hepcidin were associated with ID in highly trained runners. METHODS: Fifty-four collegiate runners (26 males and 28 females) living at ∼1625 m were recruited from an NCAA Division I cross-country team for this prospective cohort study. Over 2 seasons, fasted, preexercise blood draws were performed in the morning 4 times per season and were analyzed for hemoglobin concentration, ferritin, soluble transferrin receptor (sTfR), hepcidin, and 10 cytokines. Stages of ID were defined using ferritin, sTfR, and hemoglobin concentration. During the study, a registered dietician provided all runners with iron supplements using athletic department-created guidelines. RESULTS: Fifty-seven percent of females and 35% of males exhibited stage 2 ID (ferritin <20 ng/mL or sTfR >29.5 nmol/L) at least once. Cytokines, ferritin, and sTfR exhibited changes through the 2 years, but changes in cytokines were not associated with alterations in hepcidin, ferritin, or sTfR. In males and females, lower ferritin was associated with lower hepcidin (both P < .0001). One female exhibited higher hepcidin and lower iron stores compared with other individuals, suggesting a different etiology of ID. CONCLUSION: ID is common in highly trained collegiate runners. In general, the high prevalence of ID in this population is not associated with alterations in basal hepcidin or cytokine levels.

Understanding the Effects of Associated Factors in the Development of Microsponge-Based Drug Delivery: a Statistical Quality by Design (QbD) Approach Towards Optimization.

The investigation aims to prepare, identify, analyse, and understand the effects of different variables and constant factors associated with developing drug-loaded microsponge formulation by altering variables using the experiment's design. A series of drug formulations were prepared by alteration of variables using the design of experiment (DoE). Shape factors were kept constant. Response surface methodology (RSM) was utilized to optimize the preparation and analyse factors and variables. The RSM and QbD make the process easy to scale up and reproducible to minimize batch-to-batch variation. Critical process attributes (CPAs), such as particle size, yield, and drug entrapment, were analysed and comprehended in the development process to estimate the risk of microsponge-based formulation and method stability. Critical process parameters (CPPs) were identified by trial and error. QbD-driven quasi-emulsion solvent evaporation method was adopted to emulsify the dispersed phase within a continuous aqueous phase to develop the microsponges. The investigation confirmed that the effects of changes in controlling factors were most prominent on response variables. Each response was found in a broad range in terms of average particle diameter (337-461 µm), entrapment efficiency (77.69-94.38%) of the drug, and product yield (76.91-96.38%). The optimum results are a yield of ~ 96%, an average particle size of 347 µm, and entrapment efficiency of ~ 93.55%. An analysis of ANOVA (P value < 0.05) and models were validated. A constant rate of drug release from the optimized product was observed for a period (8 h) with a drug release of 75%. The developed method is reproducible, stable, and reliable.

Risk of Concussion After a Targeting Foul in Collegiate American Football.

BACKGROUND: The targeting rule was adopted by the National Collegiate Athletic Association (NCAA) in 2008 to discourage dangerous contact during collegiate American football competition. Although targeting rules have been emphasized as a means to reduce concussion rates, there is currently no evidence that targeting plays are higher risk for concussion than other plays in American football. PURPOSE: To compare the rate of concussion occurring during targeting versus nontargeting plays in American collegiate football. STUDY DESIGN: Cross-sectional study. METHODS: Concussions occurring in games in the 2016-2019 Pac-12 Conference were classified as having occurred during either (1) a play where a targeting penalty was called or (2) all other plays. Targeting plays were further categorized to either those in which the call was upheld or those overturned by the on-field official after replay review. The number of targeting plays and the total number of plays during games were also recorded. Concussion incidence (per 1000 plays) and risk ratios were calculated. RESULTS: Overall, 538 games with 68,670 plays were reviewed, during which 213 concussions occurred (15 during plays where targeting was called and 198 on other plays) and 141 targeting penalties were called. The incidence of concussion was 106.4/1000 plays for targeting plays (including 141.2/1000 upheld targeting fouls and 53.6/1000 overturned targeting fouls) and 2.9/1000 plays for nontargeting plays. The risk of concussion during targeting plays was 36.9 (95% CI, 22.4-60.7) times greater than that for all other plays. The risk of concussion during targeting plays upheld was 49.0 (95% CI, 28.5-84.2) times greater than that for all other plays. CONCLUSION: Concussion risk was significantly higher during plays in which targeting was called, especially those in which targeting fouls were upheld. CLINICAL RELEVANCE: This study supports eliminating or reducing targeting from American football. The results of this study suggest that players should be screened for concussion after targeting plays are called.

Obesity and sex influence fatty infiltration of the rotator cuff: the Rotator Cuff Outcomes Workgroup (ROW) and Multicenter Orthopaedic Outcomes Network (MOON) cohorts.

BACKGROUND: Fatty infiltration (FI) is one of the most important prognostic factors for outcomes after rotator cuff surgery. Established risk factors include advancing age, larger tear size, and increased tear chronicity. A growing body of evidence suggests that sex and obesity are associated with FI; however, data are limited. METHODS: We recruited 2 well-characterized multicenter cohorts of patients with rotator cuff tears (Multicenter Orthopaedic Outcomes Network [MOON] cohort [n = 80] and Rotator Cuff Outcomes Workgroup [ROW] cohort [n = 158]). We used multivariable logistic regression to evaluate the relationship between body mass index (BMI) and the presence of FI while adjusting for the participant's age at magnetic resonance imaging, sex, and duration of shoulder symptoms, as well as the cross-sectional area of the tear. We analyzed the 2 cohorts separately and performed a meta-analysis to combine estimates. RESULTS: A total of 27 patients (33.8%) in the Multicenter Orthopaedic Outcomes Network (MOON) cohort and 57 patients (36.1%) in the Rotator Cuff Outcomes Workgroup (ROW) cohort had FI. When BMI < 25 kg/m2 was used as the reference category, being overweight was associated with a 2.37-fold (95% confidence interval [CI], 0.77-7.29) increased odds of FI and being obese was associated with a 3.28-fold (95% CI, 1.16-9.25) increased odds of FI. Women were 4.9 times (95% CI, 2.06-11.69) as likely to have FI as men. CONCLUSIONS: Among patients with rotator cuff tears, obese patients had a substantially higher likelihood of FI. Further research is needed to assess whether modifying BMI can alter FI in patients with rotator cuff tears. This may have significant clinical implications for presurgical surgical management of rotator cuff tears. Sex was also significantly associated with FI, with women having higher odds of FI than men. Higher odds of FI in female patients may also explain previously reported early suboptimal outcomes of rotator cuff surgery and higher pain levels in female patients as compared with male patients.

Diagnostic accuracy and reliability of sideline concussion evaluation: a prospective, case-controlled study in college athletes comparing newer tools and established tests.

OBJECTIVE: To assess diagnostic accuracy and reliability of sideline concussion tests in college athletes. METHODS: Athletes completed baseline concussion tests including Post-Concussion Symptom Scale, Standardised Assessment of Concussion (SAC), modified Balance Error Scoring System (m-BESS), King-Devick test and EYE-SYNC Smooth Pursuits. Testing was repeated in athletes diagnosed acutely with concussion and compared to a matched teammate without concussion. RESULTS: Data were collected on 41 concussed athletes and 41 matched controls. Test-retest reliability for symptom score and symptom severity assessed using control athletes was 0.09 (-0.70 to 0.88) and 0.08 (-1.00 to 1.00) (unweighted kappa). Intraclass correlations were SAC 0.33 (-0.02 to 0.61), m-BESS 0.33 (-0.2 to 0.60), EYE-SYNC Smooth Pursuit tangential variability 0.70 (0.50 to 0.83), radial variability 0.47 (0.19 to 0.69) and King-Devick test 0.71 (0.49 to 0.84). The maximum identified sensitivity/specificity of each test for predicting clinical concussion diagnosis was: symptom score 81%/94% (3-point increase), symptom severity score 91%/81% (3-point increase), SAC 44%/72% (2-point decline), m-BESS 40%/92% (5-point increase), King-Devick 85%/76% (any increase in time) and EYE-SYNC Smooth Pursuit tangential variability 48%/58% and radial variability 52%/61% (any increase). Adjusted area under the curve was: symptom score 0.95 (0.89, 0.99), symptom severity 0.95 (95% CI 0.88 to 0.99), SAC 0.66 (95% CI 0.54 to 0.79), m-BESS 0.71 (0.60, 0.83), King-Devick 0.78 (0.69, 0.87), radial variability 0.47 (0.34, 0.59), tangential variability 0.41 (0.30, 0.54) CONCLUSION: Test-retest reliability of most sideline concussion tests was poor in uninjured athletes, raising concern about the accuracy of these tests to detect new concussion. Symptom score/severity had the greatest sensitivity and specificity, and of the objective tests, the King-Devick test performed best.

Pac-12 CARE-Affiliated Program: structure, methods and initial results.

Sport-related concussion has garnered increasing scientific attention and research over the last decade. Collegiate student-athletes represent an important cohort in this field. As such, the Pac-12 CARE-Affiliated Program (CAP) was formed in 2017 as a regional hub of the Concussion Assessment, Research and Education (CARE) consortium. CAP is multisite, prospective, longitudinal study that aims to improve student-athlete health by identifying factors associated with concussion incidence and recovery and using this knowledge to inform best clinical practices and policy decisions. CAP employed a staggered rollout across the Pac-12, with the first four institutions enrolling in fall 2018. After receiving institutional review board (IRB) approval, these institutions began consenting student-athletes to share clinical concussion and baseline data for research purposes. Athletes completed baseline testing that included a medical questionnaire, concussion history and a battery for clinical concussion assessments. Concussed student-athletes were given the same battery of assessments in addition to full injury and return to play reports. Clinicians at each university worked with a data coordinator to ensure appropriate reporting, and the Pac-12 Concussion Coordinating Unit at the University of Colorado Boulder provided oversight for quality control of the data study wide. During year 1, CAP consented 2181 student-athletes and tracked 140 concussions. All research was conducted with the appropriate IRB approval across the participating Pac-12 institutions. Data security and dissemination are managed by the Presagia Sports Athlete Electronic Health Record software (Montreal, Quebec, Canada) and QuesGen Systems (San Francisco, California, USA).

Effect of foam densification and impact velocity on the performance of a football helmet using computational modeling.

The NFL recently released validated helmet-impact models to study the performance of currently used helmets. This study used the model of a Riddell Speed Classic helmet to determine the influence of the properties of protective foam padding on acceleration and deformation at two common impact locations to cause concussions. The performance of the helmet was measured before and after manipulating the material properties of the protective foam liner material using FEA software. The densification strain was adjusted by using the scale factor tool in LS-DYNA to create four material categories - soft, standard, stiff, and rigid. The helmet was tested under side and rear impacts using the four material properties at 2.0, 5.5, 7.4, 9.3 and 12.3 m/s impact speeds using the NOCSAE linear impactor model. This study suggests that the standard foam material compresses to a range that could be considered to have "bottomed out" at impact speeds at 5.5 m/s for side impacts. Despite testing a wide range of material properties, the measured accelerations did not vary dramatically across material properties. Rather, impact speed played the dominant role on measured acceleration. This is the first study to demonstrate how open-source impact models can be used to run a design of experiments and investigate the role between different materials used inside a helmet and football helmet performance.