ABSTRACT
CONTEXT: Guardian Caps (GCs) are currently the most popular external helmet-add on designed to reduce the head impact magnitude experienced by American football players. GCs have been endorsed by influential professional organizations, however few studies evaluating the efficacy of GCs are publicly available. OBJECTIVE: The objective of this study is to present preliminary on-field head kinematics data for NCAA Division I American football players using instrumented mouthguards through closely matched pre-season workouts both with and without GCs. DESIGN: Case Series. SETTING: The study took place during the 2022 American football pre-season. PATIENTS OR OTHER PARTICIPANTS: 25 Male NCAA Division I student-athletes participating in American football completed some portion of the 6 workouts included in this study. Of the 25 total participants, 7 completed all 6 workouts using their instrumented mouthguards. MAIN OUTCOME MEASURE(S): The peak linear acceleration (PLA), peak angular acceleration (PAA) and total impacts were collected using instrumented mouthguards (iMG) during 3 pre-season workouts using traditional helmets (TRAD), and 3 with Guardian Caps used in additional to a traditional helmet (GC). The TRAD and GC values for PLA, PAA and total impacts were analyzed using ANOVAs. RESULTS: There was no significant difference between the collapsed mean values for the entire sample between TRAD and GC for PLA (TRAD=16.3±2.0, GC=17.2±3.3Gs; p=0.20), PAA (TRAD=992.1±209.2, GC=1029.4±261.1rad/s2; p=0.51 and the total amount of impacts (TRAD=9.3±4.7, GC=9.7±5.7; p=0.72). Similarly, no difference was observed between TRAD and GC for PLA (TRAD=16.1±1.2, GC=17.2±2.79Gs; p=0.32), PAA (TRAD=951.2±95.4, GC=1038.0±166.8rad/s2; p=0.29 and total impacts (TRAD=9.6±4.2, GC=9.7±5.04s; p=0.32) between sessions for the7 repeated players. CONCLUSIONS: These data suggest no difference in head kinematics data (PLA, PAA and total impacts) when GCs are worn. This study suggests GCs may not be effective in reducing the magnitude of head impacts experienced by NCAA Division I American football players.
ABSTRACT
Purpose The objective of this study is to present preliminary on-field head kinematics data for NCAA Division I American football players through closely matched pre-season workouts both with and without Guardian Caps (GCs). Methods 42 NCAA Division I American football players wore instrumented mouthguards (iMMs) for 6 closely matched workouts, 3 in traditional helmets (PRE) and 3 with GCs (POST) affixed to the exterior of their helmets. This includes 7 players who had consistent data through all workouts. Results There was no significant difference between the collapsed mean values for the entire sample between PRE and POST for peak linear acceleration (PLA) (PRE=16.3, POST=17.2Gs; p=0.20), Peak Angular Acceleration (PAA) (PRE=992.1, POST=1029.4rad/s2; p=0.51 and the total amount of impacts (PRE=9.3, POST=9.7; p=0.72). Similarly, no difference was observed between PRE and POST for PLA (PRE=16.1, POST=17.2Gs; p=0.32), PAA (PRE=951.2, POST=1038.0rad/s2; p=0.29 and total impacts (PRE=9.6, POST=9.7; p=0.32) between sessions for the 7 repeated players. Conclusion These data suggest no difference in head kinematics data (PLA, PAA and total impacts) when GCs are worn. This study suggests GCs are not effective in reducing the magnitude of head impacts experienced by NCAA Division I American football players.
ABSTRACT
CONTEXT: The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is one of the most widely used computerized neurocognitive assessment batteries in athletics, serving as both a baseline and post-injury assessment. It has become increasingly popular to administer the ImPACT baseline test in an un-supervised remote environment, however, it is unknown if the lack of supervision affects the test-retest reliability. OBJECTIVE: To establish the minimal detectable change (MDC) of composite scores from the ImPACT test when administered to National Collegiate Athletic Association (NCAA) Division I student-athletes in an un-supervised remote environment before two consecutive athletic seasons. DESIGN: Cross-Sectional. SETTING: Participants were provided with a unique link and detailed written instructions on how to complete the ImPACT test at home. PATIENTS OR OTHER PARTICIPANTS: NCAA Division I student-athletes. MAIN OUTCOME MEASURE(S): Remote ImPACT baseline test results from the 2020-2021 and 2021-2022 athletic seasons were analyzed. The MDC was calculated at the 95%, 90%, and 80% confidence intervals for each of the ImPACT composite scores, as well as the average and standard deviation. RESULTS: The MDC at the 95% confidence interval was found to be 18.6 for the verbal memory composite score, 24.44 for visual memory, 8.76 for visual motor, 0.14 for reaction time, and 6.13 for impulse control. One-way repeated measures MANOVA, repeated measures ANOVA, and Wilcoxon signed-ranks test all suggest no significant difference between the composite scores and impulse control between time points. CONCLUSIONS: The ImPACT test composite scores and impulse control did not significantly change between the two remote testing time points when administered approximately a year between testing. Our study suggests the MDC serve as a clinician's guide for evaluating changes in ImPACT baseline scores and in making clinical judgments on sports-related concussion when the test is administered at home.
ABSTRACT
OBJECTIVE: To evaluate the performance and test-retest reliability obtained when administering a computerized baseline neurocognitive exam to NCAA Division I student-athletes in a controlled laboratory setting versus an uncontrolled remote location. METHOD: A sample of 129 (female = 100) Division I student-athletes completed Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) pre-season assessments for two distinct and respective sports seasons in a controlled laboratory environment and an uncontrolled remote environment. Depending on the environment, participants were given verbal (controlled) or written (uncontrolled) guidelines for taking the test. RESULTS: Multivariate repeated-measures ANOVA's determined that there were no within-subject differences between testing environments on ImPACT composite scores and cognitive efficiency index (CEI). The Chi-square test did not find any significant differences in impulse control or the number of invalid test scores, as determined by ImPACT, between environments. Intraclass correlations found the ImPACT subtest scores to range in test-retest reliability across testing environments, demonstrating moderate (verbal memory composite, r = 0.46; visual memory composite, r = 0.64; reaction time, r = 0.61; impulse control, r = 0.52; and CEI, r = 0.61) and good (visual motor composite, r = 0.77) test-retest reliability. CONCLUSIONS: Results indicate that ImPACT is reliable between controlled and uncontrolled testing environments. This further suggests that ImPACT can be administered in a remote environment, pending specific adherence to testing instructions, or in the event of social distancing or isolation policies.
