Subconcussive brain vital signs changes predict head-impact exposure in ice hockey players.

The brain vital signs framework is a portable, objective, neurophysiological evaluation of brain function at point-of-care. We investigated brain vital signs at pre- and post-season for age 14 or under (Bantam) and age 16-20 (Junior-A) male ice hockey players to (i) further investigate previously published brain vital sign results showing subconcussive cognitive deficits and (ii) validate these findings through comparison with head-impact data obtained from instrumented accelerometers. With a longitudinal study design, 23 male ice hockey players in Bantam (n = 13; age 13.63 ± 0.62) and Tier II Junior-A (n = 10; age 18.62 ± 0.86) divisions were assessed at pre- and post-season. None were diagnosed with a concussion during the season. Cognitive evoked potential measures of Auditory sensation (N100), Basic attention (P300) and Cognitive processing (N400) were analysed as changes in peak amplitudes and latencies (six standard scores total). A regression analysis examined the relationship between brain vital signs and the number of head impacts received during the study season. Significant pre/post differences in brain vital signs were detected for both groups. Bantam and Junior-A players also differed in number of head impacts (Bantam: 32.92 ± 17.68; Junior-A: 195.00 ± 61.08; P < 0.001). Importantly, the regression model demonstrated a significant linear relationship between changes in brain vital signs and total head impacts received (R = 0.799, P = 0.007), with clear differences between the Bantam and Junior-A groups. In the absence of a clinically diagnosed concussion, the brain vital sign changes appear to have demonstrated the compounding effects of repetitive subconcussive impacts. The findings underscored the importance of an objective physiological measure of brain function along the spectrum of concussive impacts.

Proceedings From the Ice Hockey Summit III: Action on Concussion.

OBJECTIVES: The Ice Hockey Summit III provided updated scientific evidence on concussions in hockey to inform these 5 objectives: (1) describe sport related concussion (SRC) epidemiology; (2) classify prevention strategies; (3) define objective, diagnostic tests; (4) identify treatment; and (5) integrate science and clinical care into prioritized action plans and policy. METHODS: Our action plan evolved from 40 scientific presentations. The 155 attendees (physicians, athletic trainers, physical therapists, nurses, neuropsychologists, scientists, engineers, coaches, and officials) voted to prioritize these action items in the final Summit session. RESULTS: To (1) establish a national and international hockey database for SRCs at all levels; (2) eliminate body checking in Bantam youth hockey games; (3) expand a behavior modification program (Fair Play) to all youth hockey levels; (4) enforce game ejection penalties for fighting in Junior A and professional hockey leagues; (5) establish objective tests to diagnose concussion at point of care; and (6) mandate baseline testing to improve concussion diagnosis for all age groups. CONCLUSIONS: Expedient implementation of the Summit III prioritized action items is necessary to reduce the risk, severity, and consequences of concussion in the sport of ice hockey.

Concussions in Ice Hockey - Moving Toward Objective Diagnoses and Point-of-care Treatment: A Review.

The incidence of sport-related concussion coupled with a doubling of the participation rate in youth hockey over the past two decades provides impetus for the review of the most promising concussion treatment options. This narrative review summarizes the future treatment options for sport-related concussions in ice hockey, while acknowledging their generalizability to concussion in all sports. Symptom assessment, sign observation, as well as cognitive and balance testing, have historically been used to diagnose a concussion. These methods continue to improve, but the need for effective treatments is clear. Pharmacologic, transcranial light, and nutritional supplement treatment options for concussion warranting further investigation have been identified. Dimethyl fumarate is an immunomodulatory compound thought to trigger antioxidant gene expression. Memantine reduces apoptosis and astrogliosis by inhibiting the calcium influx into cells normally caused by glutamate's activation of N-methyl-D-aspartate receptors. Thioredoxin-mimetic peptides and transcranial photobiomodulation temper the effects of the energy crisis by acting as free radical scavengers. In addition, seven neuroprotective nutritional supplements have been identified: berberine, creatine, curcumin, melatonin, omega-3 fatty acids, resveratrol, and vitamins. An estimated US $1.1 billion has been spent on unsuccessful traumatic brain injury clinical trials. As our ability to accurately diagnose concussion improves, dimethyl fumarate, memantine, thioredoxin-mimetic peptides, transcranial photobiomodulation, and nutritional supplements (berberine, creatine, curcumin, melatonin, omega-3 fatty acids, resveratrol, and vitamins) warrant further preclinical and clinical examination in advancing the treatment of sport-related concussions.

Brain vital signs detect concussion-related neurophysiological impairments in ice hockey.

There is a growing demand for objective evaluations of concussion. We developed a portable evoked potential framework to extract 'brain vital signs' using electroencephalography. Brain vital signs were derived from well established evoked responses representing auditory sensation (N100), basic attention (P300), and cognitive processing (N400) amplitudes and latencies, converted to normative metrics (six total). The study evaluated whether concussion-related neurophysiological impairments were detected over the duration of ice hockey seasons using brain vital signs. Forty-seven Tier III, Junior A, male ice hockey players were monitored over two seasons. Twelve sustained concussions after baseline testing then completed post-injury and return-to-play assessments. Twenty-three were not diagnosed with a concussion during the season and completed both baseline and post-season testing. Scores were evaluated using a repeated-measures analysis of variance with post hoc two-tailed paired t-tests. Concussion resulted in significantly increased amplitude and delayed latency scores for all six brain vital signs (P < 0.0001). Importantly, significant changes at return-to-play were also detected in basic attention (P300) amplitude, indicating persistent subclinical impairment. In the non-concussed group, there was also a significant change between baseline and post-season (P = 0.0047), with specific decreases in cognitive processing (N400) speed (P = 0.011) and overall total score (P = 0.002).

Proceedings from the Ice Hockey Summit III: Action on Concussion.

The Ice Hockey Summit III provided updated scientific evidence on concussions in hockey to inform these five objectives: 1) describe sport-related concussion (SRC) epidemiology, 2) classify prevention strategies, 3) define objective, diagnostic tests, 4) identify treatment, and 5) integrate science and clinical care into prioritized action plans and policy. Our action plan evolved from 40 scientific presentations. The 155 attendees (physicians, athletic trainers, physical therapists, nurses, neuropsychologists, scientists, engineers, coaches, and officials) voted to prioritize these action items in the final Summit session. 1) Establish a national and international hockey data base for SRC at all levels, 2) eliminate body checking in Bantam youth hockey games, 3) expand a behavior modification program (Fair Play) to all youth hockey levels, 4) enforce game ejection penalties for fighting in Junior A and professional hockey leagues, 5) establish objective tests to diagnose concussion at point of care (POC), and 6) mandate baseline testing to improve concussion diagnosis for all age groups. Expedient implementation of the Summit III prioritized action items is necessary to reduce the risk, severity, and consequences of concussion in the sport of ice hockey.

Eliminating Fighting and Head Hits from Hockey: Opportunities and Barriers.

Removing fighting from ice hockey is an essential concussion prevention strategy that will improve the safety of the game at all levels.

Concussion in Ice Hockey: Current Gaps and Future Directions in an Objective Diagnosis.

OBJECTIVE: This review provides an update on sport-related concussion (SRC) in ice hockey and makes a case for changes in clinical concussion evaluation. Standard practice should require that concussions be objectively diagnosed and provide quantitative measures of the concussion injury that will serve as a platform for future evidence-based treatment. METHODS: The literature was surveyed to address several concussion-related topics: research in ice hockey-related head trauma, current subjective diagnosis, promising components of an objective diagnosis, and current and potential treatments. MAIN RESULTS: Sport-related head trauma has marked physiologic, pathologic, and psychological consequences for athletes. Although animal models have been used to simulate head trauma for pharmacologic testing, the current diagnosis and subsequent treatment in athletes still rely on an athlete's motivation to report or deny symptoms. Bias-free, objective diagnostic measures are needed to guide quantification of concussion severity and assessment of treatment effects. Most of the knowledge and management guidelines of concussion in ice hockey are generalizable to other contact sports. CONCLUSIONS: There is a need for an objective diagnosis of SRC that will quantify severity, establish a prognosis, and provide effective evidence-based treatment. Potential methods to improve concussion diagnosis by health care providers include a standardized concussion survey, the King-Devick test, a quantified electroencephalogram, and blood analysis for brain cell-specific biomarkers.

Does fair play reduce concussions? A prospective, comparative analysis of competitive youth hockey tournaments.

BACKGROUND/AIM: To determine if Boys Bantam and Peewee and Girls U14 sustain fewer concussions, head hits, 'other injuries' and penalties in hockey tournaments governed by intensified fair play (IFP) than non-intensified fair play (NIFP). METHODS: A prospective comparison of IFP, a behaviour modification programme that promotes sportsmanship, versus control (non-intensified, NIFP) effects on numbers of diagnosed concussions, head hits without diagnosed concussion (HHWDC), 'other injuries', number of penalties and fair play points (FPPs). 1514 players, ages 11-14 years, in 6 IFP (N=950) and 5 NIFP (N=564) tournaments were studied. RESULTS: Two diagnosed concussions, four HHWDC, and six 'other injuries' occurred in IFP tournaments compared to one concussion, eight HHWDC and five 'other injuries' in NIFP. There were significantly fewer HHWDC in IFP than NIFP (p=0.018). However, diagnosed concussions, 'other injuries', penalties and FPPs did not differ significantly between conditions. In IFP, a minority of teams forfeited the majority of FPPs. Most diagnosed concussions, HHWDC, and other injuries occurred to Bantam B players and usually in penalised teams that forfeited their FPPs. CONCLUSIONS: In response to significant differences in HHWDC between IFP and NIFP tournaments, the following considerations are encouraged: mandatory implementation of fair play in regular season and tournaments, empowering tournament directors to not accept heavily penalised teams, and introducing 'no body checking' in Bantam.

Developing Brain Vital Signs: Initial Framework for Monitoring Brain Function Changes Over Time.

Clinical assessment of brain function relies heavily on indirect behavior-based tests. Unfortunately, behavior-based assessments are subjective and therefore susceptible to several confounding factors. Event-related brain potentials (ERPs), derived from electroencephalography (EEG), are often used to provide objective, physiological measures of brain function. Historically, ERPs have been characterized extensively within research settings, with limited but growing clinical applications. Over the past 20 years, we have developed clinical ERP applications for the evaluation of functional status following serious injury and/or disease. This work has identified an important gap: the need for a clinically accessible framework to evaluate ERP measures. Crucially, this enables baseline measures before brain dysfunction occurs, and might enable the routine collection of brain function metrics in the future much like blood pressure measures today. Here, we propose such a framework for extracting specific ERPs as potential "brain vital signs." This framework enabled the translation/transformation of complex ERP data into accessible metrics of brain function for wider clinical utilization. To formalize the framework, three essential ERPs were selected as initial indicators: (1) the auditory N100 (Auditory sensation); (2) the auditory oddball P300 (Basic attention); and (3) the auditory speech processing N400 (Cognitive processing). First step validation was conducted on healthy younger and older adults (age range: 22-82 years). Results confirmed specific ERPs at the individual level (86.81-98.96%), verified predictable age-related differences (P300 latency delays in older adults, p < 0.05), and demonstrated successful linear transformation into the proposed brain vital sign (BVS) framework (basic attention latency sub-component of BVS framework reflects delays in older adults, p < 0.05). The findings represent an initial critical step in developing, extracting, and characterizing ERPs as vital signs, critical for subsequent evaluation of dysfunction in conditions like concussion and/or dementia.

Ice Hockey Summit II: zero tolerance for head hits and fighting.

OBJECTIVE: To present currently known basic science and on-ice influences of sport-related concussion (SRC) in hockey, building on the Ice Hockey Summit I action plan (2011) to reduce SRC. METHODS: The prior summit proceedings included an action plan intended to reduce SRC. As such, the proceedings from Summit I served as a point of departure, for the science and discussion held during Summit II (Mayo Clinic, Rochester MN, October 2013). Summit II focused on (1) Basic Science of Concussions in Ice Hockey: Taking Science Forward; (2) Acute and Chronic Concussion Care: Making a Difference; (3) Preventing Concussions via Behavior, Rules, Education and Measuring Effectiveness; (4) Updates in Equipment: their Relationship to Industry Standards; and (5) Policies and Plans at State, National and Federal Levels to reduce SRC. Action strategies derived from the presentations and discussion described in these sectors were subsequently voted on for purposes of prioritization. The following proceedings include knowledge and research shared by invited faculty, many of whom are health care providers and clinical investigators. RESULTS: The Summit II evidence-based action plan emphasizes the rapidly evolving scientific content of hockey SRC. It includes the most highly prioritized strategies voted on for implementation to decrease concussion. CONCLUSIONS: The highest priority action items identified from the Summit includes the following: (1) eliminate head hits from all levels of ice hockey, (2) change body-checking policies, and (3) eliminate fighting in all amateur and professional hockey.

Ice hockey summit II: zero tolerance for head hits and fighting.

OBJECTIVE: To present currently known basic science and on-ice influences of sport related concussion (SRC) in hockey, building upon the Ice Hockey Summit I action plan (2011) to reduce SRC. METHODS: The prior summit proceedings included an action plan intended to reduce SRC. As such, the proceedings from Summit I served as a point of departure, for the science and discussion held during Summit II (Mayo Clinic, Rochester MN, October, 2013). Summit II focused on Basic Science of Concussions in Ice Hockey: Taking Science Forward; (2) Acute and Chronic Concussion Care: Making a Difference; (3) Preventing Concussions via Behavior, Rules, Education and Measuring Effectiveness; (4) Updates in Equipment: their Relationship to Industry Standards and (5) Policies and Plans at State, National and Federal Levels to reduce SRC. Action strategies derived from the presentations and discussion described in these sectors were subsequently voted on for purposes of prioritization. The following proceedings include the knowledge and research shared by invited faculty, many of whom are health care providers and clinical investigators. RESULTS: The Summit II evidence based action plan emphasizes the rapidly evolving scientific content of hockey SRC. It includes the most highly prioritized strategies voted on for implementation to decrease concussion. CONCLUSIONS: The highest priority action items identified from the Summit include: 1) eliminate head hits from all levels of ice hockey, 2) change body checking policies, and 3) eliminate fighting in all amateur and professional hockey.

Ice Hockey Summit II: zero tolerance for head hits and fighting.

This study aimed to present currently known basic science and on-ice influences of sport-related concussion (SRC) in hockey, building upon the Ice Hockey Summit I action plan (2011) to reduce SRC. The prior summit proceedings included an action plan intended to reduce SRC. As such, the proceedings from Summit I served as a point of departure for the science and discussion held during Summit II (Mayo Clinic, Rochester, MN, October 2013). Summit II focused on (1) Basic Science of Concussions in Ice Hockey: Taking Science Forward, (2) Acute and Chronic Concussion Care: Making a Difference, (3) Preventing Concussions via Behavior, Rules, Education, and Measuring Effectiveness, (4) Updates in Equipment: Their Relationship to Industry Standards, and (5) Policies and Plans at State, National, and Federal Levels To Reduce SRC. Action strategies derived from the presentations and discussion described in these sectors were voted on subsequently for purposes of prioritization. The following proceedings include the knowledge and research shared by invited faculty, many of whom are health care providers and clinical investigators. The Summit II evidence-based action plan emphasizes the rapidly evolving scientific content of hockey SRC. It includes the most highly prioritized strategies voted on for implementation to decrease concussion. The highest-priority action items identified from the Summit include the following: (1) eliminate head hits from all levels of ice hockey, (2) change body checking policies, and (3) eliminate fighting in all amateur and professional hockey.

The most cut-resistant neck guard for preventing lacerations to the neck.

OBJECTIVE: To evaluate the effectiveness of a variety of neck guard brands when contacted by a sharpened hockey skate blade. DESIGN: Analytic experimental. SETTING: Laboratory. PARTICIPANTS: Neck surrogate. INTERVENTIONS: Forty-six samples of 14 different types of neck guards were tested on a custom-made laceration machine using a neck surrogate. Closed-cell polyethylene foam was placed between the neck surrogate and the protective device. MAIN OUTCOME MEASURES: The effectiveness of the neck guard was evaluated by observation of the foam after the simulated slicing action of the skate blade. Two sets of tests were performed on each device sample including low and high force. For low-force tests, initial compression loads of 100, 200, and 300 N were applied between the neck surrogate for each of 2 orientations of the blade at 45 and 90 degrees. For high-force tests, representing a more severe simulation, the applied load was increased to 600 N and a blade angle fixed at 45 degrees. All tests were performed at a blade speed of 5 m/s. RESULTS: Only 1 product, the Bauer N7 Nectech, failed during the 300-N compression tests. All of the neck guards failed during 600-N test condition except for the Skate Armor device and 1 of the 3 Reebok 11K devices. CONCLUSIONS: A skate blade angle of 45 degrees increased the likelihood of a neck laceration compared with a skate blade angle of 90 degrees due to decreased contact area. Damage to the neck guard is not an indicator of the cut resistance of a neck guard. Neck protectors with Spectra fibers were the most cut resistant. CLINICAL RELEVANCE: The study provides data for the selection of neck guards and neck guard materials that can reduce lacerations to the neck.

Examining computerized software reliability to measure individual exposure time.

OBJECTIVE: Epidemiological sport injury research lacks relevance when all athletes are assumed to have equal time exposed to risk. Because athletes do not play equal minutes in ice hockey games, it is important to control for players' individual exposure times (IETs) when studying risk factors for injury. DESIGN: Cohort study. SETTING: Hockey games. PARTICIPANTS: Twenty-eight Minnesota Junior A hockey players. INTERVENTIONS: Individual exposure times were measured on all players dressed for their home games using both a manual (game clock, paper, and pencil) and a computer-based system [Time on Ice (TOI) software]. A sample of matched records was evaluated to compare the 2 methods of recording exposure. MAIN OUTCOME MEASURES: Values of individual player exposure times obtained by TOI software designed for hockey and the manual recording method were compared. RESULTS: Individual exposure times were measured simultaneously by computer-based and manual methods. For 26 games, it would require 156 hours to determine IET per game by the manual method. Conversely, IET totals on TOI software were computed automatically for each player per game. When IET was compared across periods and games, the computer analysis consistently totaled more IET than the manual method. CONCLUSIONS: Time on Ice software was user friendly, required no postgame processing, and showed a high degree of correlation to manually recorded times, although consistently higher IET per player per period than the manual method was noted.

Skating crossovers on a motorized flywheel: a preliminary experimental design to test effect on speed and on crossovers.

Ice hockey requires frequent skater crossovers to execute turns. Our investigation aimed to determine the effectiveness of training crossovers on a motorized, polyethylene high-resistance flywheel. We hypothesized that high school hockey players training on the flywheel would perform as well as their peers training on ice. Participants were 23 male high-school hockey players (age 15-19 years). The study used an experimental prospective design to compare players who trained for 9 sessions on the 22-foot flywheel with players who trained for 9 sessions on a similarly sized on-ice circle. Both groups were compared with control subjects who were randomly selected from the same participant pool as those training on ice. All players were tested before and after their 3-week training regimens, and control subjects were asked to not practice crossovers between testing. Group 1 trained in a hockey training facility housing the flywheel, and group 2 trained in the ice hockey arena where testing occurred. Primary outcome measures tested in both directions were: (a) speed (time in seconds) required to skate crossovers for 3 laps of a marked face-off circle, (b) cadence of skating crossovers on the similarly sized circles, and (c) a repeat interval speed test, which measures anaerobic power. No significant changes were found between groups in on-ice testing before and after training. Among the group 1 players, 7 of 8 believed they benefited from flywheel training. Group 2 players, who trained on ice, did not improve performance significantly over group 1 players. Despite the fact that no significant on-ice changes in performance were observed in objective measures, players who trained on the flywheel subjectively reported that the flywheel is an effective cost-effective alternative to training on ice. This is a relevant finding when placed in context with limited availability of on-ice training.

Psychosocial benefits and implications of exercise.

This review is based on a case report that concerns a young female athlete who experienced some of the negative aspects of exercise. Overtraining, a negative byproduct of excessive exercise, can turn the positive psychosocial and physiologic benefits of regular physical activity into an activity detrimental to one's health. With the proper psychological skills and appropriate exercise regimen, these negatives can be turned into positives. Once learned, the psychosocial benefits of exercise, as well as the positive implications, will become more prevalent, similar to the way in which proper physical training helps one become more fit over time.

Relationship of off-ice and on-ice performance measures in high school male hockey players.

The purpose of this study was to examine the relationship of off-ice performance measures with on-ice turning, crossover, and forward skating performance in high school male hockey players. Thirty-eight players aged 15-18 (mean age ± SD: 16.4 ± 1.1 years; height: 177.9 ± 6.8 cm; weight: 72.5 ± 8.9 kg) participated in this study. On-ice tests included a forward sprint, short radius turns, and crossover turns. Off-ice tests included a 40-yd sprint, vertical jumps, horizontal jumps, and a dynamic balance test using a Y balance testing device. Five off-ice variables correlated with all on-ice performance measures. These variables included the 40-yd sprint, lateral bound right to left limb, double limb horizontal hop, balance on right in posterolateral direction, and composite balance performance on the right. Hierachical regression demonstrated that off-ice sprint time was most predictive of on-ice skating performance, accounting for 65.4% of the variability in forward skate time, 45.0% of the variability in left short radius time, 21.8% of the variance in right short radius time, 36.2% of the variance in left crossover time, and 30.8% of the variability in right crossover time. When using off-ice tests to evaluate hockey players, the 40-yd sprint is the best predictor of skating performance. Based on our regression equation, for every 1-second difference in the 40-yd sprint time, there will be approximately a 0.6-second difference in the 34.5-m on-ice sprint. The 40-yd sprint predicts forward skating performance and to a lesser degree; it also predicts crossover and tuning performance.