Concussion in Ice Hockey-A Cohort Study Across 29 Seasons

Shorter recovery time in concussed elite ice hockey players by early head-and-neck cooling - a clinical trial

A sports-related concussion (SRC) is most commonly sustained in contact sports, and is defined as a mild traumatic brain injury. An exercise-induced elevation of core body temperature is associated with increased brain temperature that may accelerate secondary injury processes following SRC, and exacerbate the brain injury. In a recent pilot study, acute head-neck cooling of 29 concussed ice hockey players resulted in shorter time to return-to-play. Here, we extended the clinical trial to include players of 19 male elite Swedish ice hockey teams over 5 seasons (2016-2021). In the intervention teams, acute head-neck cooling was implemented using a head cap for ≥45 minutes in addition to the standard SRC management used in controls. The primary endpoint was time from SRC until return-to-play (RTP). Sixty-one SRCs were included in the intervention group and 71 SRCs in the control group. The number of previous SRCs was 2 (median and interquartile range (IQR): 1.0 - 2.0) and 1 (IQR 1.0 - 2.0) in the intervention and control groups, respectively; p= 0.293. Median time to initiate head-neck cooling was 10 min (IQR 7-15; range 5-30 min) and median duration of cooling was 45 min (IQR 45-50; range 45-70 min). The median time to RTP was 9 days in the intervention group (IQR 7-13.5 days) and 13 days in the control group (IQR 9-30; p<0.001). The proportion of players out from play for more than the expected recovery time of 14 days was 24.7% in the intervention group, and 43.7% in controls (p<0.05). Study limitations include that a) allocation to cooling or control management was at the discretion of the medical staff of each teams, decided prior to each season, and not by strict randomization, b) no sham cap was used and evaluations could not be performed by blinded assessors and c) it could not be established with certainty that injury severity was similar between groups. While the results should thus be interpreted with caution, early head-neck cooling, with the aim of attenuating cerebral hyperthermia, may reduce post-SRC symptoms and lead to earlier return-to-play in elite ice hockey players.

Sports-Related Concussion Is a Personalized Issue—Evaluation of Medical Assessment and Subjective Feeling of the Athlete in a German Level 1 Trauma Center

Sports-related concussions (SRC) have developed into a highly discussed topic in sports medicine over the last few years and demonstrate a severe issue in the personalized treatment of patients. This retrospective cohort study investigated 86 patients with sports-related concussions in a level 1 trauma center, relating to the mechanism, symptoms, medical history, acute therapy including first assessment and the return to sport. The research is based on medical records as well as questionnaires six months after hospitalization. Loss of consciousness for under 30 min (41.2%), headache (36.5%) and amnesia (29.4%) were the most frequent symptoms when presenting in the emergency room. During the hospitalization, mainly headache and vertigo were documented. Most concussions occurred after incidents in equitation and cycling sports; the most common mechanism was falling to the ground with a subsequent impact (59.3%). At the time of discharge from hospital, in 13.4% of all cases, concussion symptoms were still documented in medical records, in contrast to 39.5% of the concerned athletes who reported symptoms for longer than 24 h, and 41.0% who reported ongoing post-concussion symptoms after six months. Concussions are difficult-to-treat disorders with a challenging diagnostic process and many symptoms in various values and levels of persistence. Therefore, a patient-involving treatment with a complaint-dependent return to sport process should be applied to concerned athletes.

Long-term postural control in elite athletes following mild traumatic brain injury

Background

Traumas to the head and neck are common in sports and often affects otherwise healthy young individuals. Sports-related concussions (SRC), defined as a mild traumatic brain injury (mTBI), may inflict persistent neck and shoulder pain, and headache, but also more complex symptoms, such as imbalance, dizziness, and visual disturbances. These more complex symptoms are difficult to identify with standard health care diagnostic procedures.

Objective

To investigate postural control in a group of former elite athletes with persistent post-concussive symptoms (PPCS) at least 6 months after the incident.

Method

Postural control was examined using posturography during quiet stance and randomized balance perturbations with eyes open and eyes closed. Randomized balance perturbations were used to examine motor learning through sensorimotor adaptation. Force platform recordings were converted to reflect the energy used to maintain balance and spectrally categorized into total energy used, energy used for smooth corrective changes of posture (i.e., <0.1 Hz), and energy used for fast corrective movements to maintain balance (i.e., >0.1 Hz).

Results

The mTBI group included 20 (13 males, mean age 26.6 years) elite athletes with PPCS and the control group included 12 athletes (9 males, mean age 26.4 years) with no history of SRC. The mTBI group used significantly more energy during balance perturbations than controls: +143% total energy, p = 0.004; +122% low frequency energy, p = 0.007; and +162% high frequency energy, p = 0.004. The mTBI subjects also adapted less to the balance perturbations than controls in total (18% mTBI vs. 37% controls, p = 0.042), low frequency (24% mTBI vs. 42% controls, p = 0.046), and high frequency (6% mTBI vs. 28% controls, p = 0.040). The mTBI subjects used significantly more energy during quiet stance than controls: +128% total energy, p = 0.034; +136% low-frequency energy, p = 0.048; and +109% high-frequency energy, p = 0.015.

Conclusion

Athletes with previous mTBI and PPCS used more energy to stand compared to controls during balance perturbations and quiet stance and had diminished sensorimotor adaptation. Sports-related concussions are able to affect postural control and motor learning.

Post-Concussive Vestibular Dysfunction Is Related to Injury to the Inferior Vestibular Nerve

Symptoms of vestibular dysfunction such as dizziness and vertigo are common after sports-related concussions (SRC) and associated with a worse outcome and a prolonged recovery. Vestibular dysfunction after SRC can be because of an impairment of the peripheral or central neural parts of the vestibular system. The aim of the present study was to establish the cause of vestibular impairment in athletes with SRC who have persisting post-concussive symptoms (PPCS). We recruited 42 participants-21 athletes with previous SRCs and PPCS ≥6 months and 21 healthy athletic age- and sex-matched controls-who underwent symptom rating, a detailed test battery of vestibular function and 7T magnetic resonance imaging with diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) of cerebellar white matter tracts, and T1-weighted imaging for cerebellar volumetrics. Vestibular dysfunction was observed in 13 SRC athletes and three controls (p = 0.001). Athletes with vestibular dysfunction reported more pronounced symptoms on the Dizziness Handicap Inventory (DHI; p < 0.001) and the Hospital Anxiety and Depression Scale (HADS; p < 0.001). No significant differences in DTI metrics were found, while in DKI two metrics were observed in the superior and/or inferior cerebellar tracts. Cerebellar gray and white matter volumes were similar in athletes with SRC and controls. Compared with controls, pathological video head impulse test results (vHIT; p < 0.001) and cervical vestibular evoked myogenic potentials (cVEMP; p = 0.002) were observed in athletes with SRC, indicating peripheral vestibular dysfunction and specifically suggesting injury to the inferior vestibular nerve. In athletes with persisting symptoms after SRC, vestibular dysfunction is associated with injury to the inferior vestibular nerve.

Effective stiffness, damping and mass of the body during laboratory simulations of shoulder checks in ice hockey

Ice hockey is a fast-paced sport with a high incidence of collisions between players. Shoulder checks are especially common, accounting for a large portion of injuries including concussions. The forces generated during these collisions depend on the inertial and viscoelastic characteristics of the impacting bodies. Furthermore, the effect of shoulder pads in reducing peak force depends on the baseline (unpadded) properties of the shoulder. We conducted experiments with nine men's ice hockey players (aged 19-26) to measure their effective shoulder stiffness, damping and mass during the impact stage of a shoulder check. Participants delivered a style of check commonly observed in men's university ice hockey, involving lateral impact to the deltoid region, with the shoulder brought stationary by the collision. The effective stiffness and damping coefficient of the shoulder averaged 12.8 kN/m and 377 N-s/m at 550 N, and the effective mass averaged 47% of total body mass. The damping coefficient and stiffness increased with increasing force, but there was no significant difference in the damping coefficient above 350 N. Our results provide new evidence on the dynamics of shoulder checks in ice hockey, as a starting point for designing test systems for evaluating and improving the protective value of shoulder pads.

Selective head-neck cooling after concussion shortens return-to-play in ice hockey players

We aimed to investigate whether selective head–neck cooling could shorten recovery after sports-related concussions (SRCs). In a nonrandomized study of 15 Swedish professional ice hockey teams, 29 concussed players received immediate head and neck cooling for ≥30 min (initiated at 12.3 ± 9.2 min post-SRC by a portable cooling system), and 52 SRC controls received standard management. Players receiving head–neck cooling had shorter time to return-to-play than controls (7 vs 12.5 days, p < 0.0001), and 7% in the intervention group versus 25% in the control group were out of play for ≥3 weeks (p = 0.07). Immediate selective head–neck cooling is a promising option in the acute management of SRC that should be addressed in larger cohorts.

Quality of life of ice hockey players after retirement due to concussions

Background:

Sports-related concussion (SRC) is increasingly recognized as a potential health problem in ice hockey. Quality of life (QoL) in players retiring due to SRC has not been thoroughly addressed.

Materials & methods:

QoL using the Sports Concussion Assessment Tool 5th Edition, Impact of Event Scale-Revised and Short Form Health Survey was measured in Swedish ice hockey players who retired due to persistence of postconcussion symptoms or fear of attaining additional SRC.

Results:

A total of 76 players were assessed, on average of 5 years after their most recent SRC. Overall, retired players had a high burden of postconcussion symptoms and reduced QoL.

Conclusion:

Retired concussed ice hockey players have a reduced QoL, particularly those retiring due to postconcussion symptoms. Symptom burden should be continuously evaluated and guide the decision to retire.

Concussions sustained while playing ice hockey are increasingly recognized as a potential health problem. Long-term consequences for players retiring due to concussions have not been fully investigated. Therefore, we evaluated symptoms, quality of life and post-traumatic stress in former Swedish ice hockey players who retired due to postconcussion symptoms or to a fear of attaining additional concussions. We found that retired ice hockey players with a history of concussions had a low quality of life and high post-traumatic stress, particularly in players with a high symptom burden. We recommend that symptom burden should be continuously evaluated and guide the decision to retire.

Losing the identity of a hockey player: the long-term effects of concussions

AIM

To describe what suffering multiple concussions meant for former semi-professional or professional hockey players who were forced to end their career.

RESULTS

Nine former Swedish hockey players, who once played on national or professional teams were interviewed. The interviews were analyzed with reference to hermeneutic phenomenology to interpret and explain their experiences. The theme of losing one's identity as a hockey player was constructed from five subthemes: being limited in everyday life, returning to the hockey stadium as soon as possible, forming a post career identity, lacking understanding and support, and preventing injuries by respecting other players.

CONCLUSION

The former hockey players struggled with developing their off-the-ice identities and with finding other sources of meaning for their lives.

Development of a test method for adult ice hockey helmet evaluation

Ice hockey helmet standards have primarily been developed to reduce risk of traumatic brain injury (TBI). While severe TBI has become a rare event in ice hockey, concussion, a type of mild TBI, remains a common head injury. Concussions, in ice hockey result from a number of head impact events including, collisions, stick impacts, puck impacts, falls into the boards, impacts to the glass, and falls to the ice. Helmet testing methods need to represent the impact events creating concussions in ice hockey. The purpose of this research was to develop a helmet test protocol and performance metric for concussive impacts in ice hockey. A protocol using concussion impact parameters from published literature was created that used monorail and linear impactors to impact a helmeted Hybrid III headform. The linear and rotational acceleration time curves were then used to calculate brain tissue strain using the University College Brain Trauma Model. The proposed test protocols created kinematic responses that were representative of levels associated with concussion in ice hockey. Rotational velocity and rotational acceleration were both identified as useful performance metrics representing levels of risk for concussion.

Management of concussion in soccer

BACKGROUND

When participating in contact sports, (mild) head trauma is a common incident-observed in both professional and amateur sports. When head trauma results in transient neurological impairment, a sports-related concussion has occurred. Acute concussion, repetitive concussions, as well as cumulative "sub-concussive" head impacts may increase the risk of developing cognitive and behavioral deficits for athletes, as well as accelerated cerebral degeneration. While this concept has been well established for classic contact sports like American Football, Rugby, or Boxing, there is still an awareness gap for the role of sports-related concussion in the context of the world's most popular sport-Soccer.

METHODS

Here, we review the relevance of sport-related concussion for Soccer as well as its diagnosis and management. Finally, we provide insight into future directions for research in this field.

RESULTS

Soccer fulfills the criteria of a contact sport and is characterized by a high incidence of concussion. There is ample evidence that these events cause functional and structural cerebral disorders. Furthermore, heading, as a repeat sub-concussive impact, has been linked to structural brain changes and neurocognitive impairment. As a consequence, recommendations for the diagnosis and management of concussion in soccer have been formulated by consensus groups. In order to minimize the risk of repetitive concussion in soccer the rapid and reliable side-line diagnosis of concussion with adoption of a strict remove-from-play protocol is essential, followed by a supervised, graduated return-to-play protocol. Recent studies, however, demonstrate that adherence to these recommendations by players, coaches, clubs, and officials is insufficient, calling for stricter enforcement. In addition, future research to solidify the pathophysiological relevance of concussion for soccer athletes seems to be needed. Advanced neuroimaging and neurochemical biomarker analyses (e.g. S100β, tau and neurofilament light (NfL)) may assist in detecting concussion-related structural brain changes and selecting athletes at risk for irreversible damage.

CONCLUSION

Sports-related concussion represents a genuine neurosurgical field of interest. Given the high socioeconomic relevance, neurosurgeons should get involved in prevention and management of concussion in soccer.

Understanding the resistance to creating safer ice hockey: essential points for injury prevention

Introduction

Despite the known negative health outcomes of concussions in minor level boys’ hockey, there has been significant resistance to creating a safer game with less body checking.

Methods

To better understand cultural barriers that prevent making the sport safer for youth and adolescents, semistructured interviews, with 20 ice hockey stakeholders, were conducted and analysed using thematic analysis.

Results

Through this analysis, two primary concepts arose from respondents. The first concept is that body checking, despite the harm it can cause, should be done in a respectful sportsmanlike fashion. The second concept is the contradiction that the game of ice hockey is both dynamic and unchangeable.

Discussion

Using structural functionalist theory, we propose an argument that the unfortunate perpetuation of violence and body checking in youth ice hockey serves to maintain the social order of the game and its culture. Any strategies aimed at modifying and promoting healthy behaviour in the game should take these concepts into account.