The Effect of Body Checking Policy Changes on Concussion Incidence in Canadian Male Youth Ice Hockey Players: A Critically Appraised Topic

Epidemiological Principles in Claims of Causality: An Enquiry into Repetitive Head Impacts (RHI) and Chronic Traumatic Encephalopathy (CTE)

Determining whether repetitive head impacts (RHI) cause the development of chronic traumatic encephalopathy (CTE)-neuropathological change (NC) and whether pathological changes cause clinical syndromes are topics of considerable interest to the global sports medicine community. In 2022, an article was published that used the Bradford Hill criteria to evaluate the claim that RHI cause CTE. The publication garnered international media attention and has since been promoted as definitive proof that causality has been established. Our counterpoint presents an appraisal of the published article in terms of the claims made and the scientific literature used in developing those claims. We conclude that the evidence provided does not justify the causal claims. We discuss how causes are conceptualised in modern epidemiology and highlight shortcomings in the current definitions and measurement of exposures (RHI) and outcomes (CTE). We address the Bradford Hill arguments that are used as evidence in the original review and conclude that assertions of causality having been established are premature. Members of the scientific community must be cautious of making causal claims until the proposed exposures and outcomes are well defined and consistently measured, and findings from appropriately designed studies have been published. Evaluating and reflecting on the quality of research is a crucial step in providing accurate evidence-based information to the public.

Headgear use in girls' lacrosse-stakeholders not ready for change

Purpose

Mandating headgear for field players in girls' lacrosse to reduce head injuries, including concussion, has been heavily debated. However, research regarding the need and effectiveness of mandated headgear use in girls' lacrosse is still developing. Therefore, this qualitative study aimed to identify the need for and barriers to the development of mandated headgear use policies in girls' lacrosse in Ohio.

Methods

We conducted six virtual focus groups, three with concussion experts (clinicians and researchers) and three with girls' lacrosse stakeholders (high school players, parents, coaches, and officials). A focus group guide was developed to explore study participants' perceptions and opinions on concussion in girls' lacrosse, headgear use among players, and policies and policy development related to headgear use or a headgear mandate. We developed the codebook using an inductive and iterative approach based on focus group transcripts and used ATLAS.TI to code and analyze the transcript data.

Results

Concussion experts and stakeholders understood the potential consequences of concussion but did not perceive concussion as a pervasive problem in girls' lacrosse. The prevention of head and facial injuries was regarded as a potential benefit of headgear use. However, stakeholders expressed that the myriad of arguments discussed opposing mandated headgear use including increased aggressive play and/or targeting, concerns over changes in the game, and cost strongly outweighed the benefits. Finally, both concussion experts and stakeholders identified multiple organizations, including USA Lacrosse, who could act as facilitators and/or barriers to developing, enacting, and implementing headgear policies.

Conclusions

Concussion experts and stakeholders identified possible reasons for headgear use related to injury prevention but also identified several important barriers to the development of a headgear mandate for girls' lacrosse in Ohio.

Operative Treatment of Cervical Spine Injuries Sustained in Youth Sports

BACKGROUND

Little data exists on surgical outcomes of sports-related cervical spine injuries (CSI) sustained in children and adolescent athletes. This study reviewed demographics, injury characteristics, management, and operative outcomes of severe CSI encountered in youth sports.

METHODS

Children below 18 years with operative sports-related CSI at a Level 1 pediatric trauma center were reviewed (2004 to 2019). All patients underwent morden cervical spine instrumentation and fusion. Clinical, radiographic, and surgical characteristics were analyzed.

RESULTS

A total of 3231 patients (mean, 11.3±4.6 y) with neck pain were evaluated for CSI. Sports/recreational activities were the most common etiology in 1358 cases (42.0%). Twenty-nine patients (2.1%) with sports-related CSI (mean age, 14.5 y; range, 6.4 to 17.8 y) required surgical intervention. Twenty-five were males (86%). Operative CSI occurred in football (n=8), wrestling (n=7), gymnastics (n=5), diving (n=4), trampoline (n=2), hockey (n=1), snowboarding (n=1), and biking (n=1). Mechanisms were 27 hyperflexion/axial loading (93%) and 2 hyperextension injuries (7%). Most were cervical fractures (79%) and subaxial injuries (79%). Seven patients (24%) sustained spinal cord injury (SCI) and 3 patients (10%) cord contusion or myelomalacia without neurological deficits. The risk of SCI increased with age (P=0.03). Postoperatively, 2 SCI patients (29%) improved 1 American Spinal Injury Association Impairment Scale Grade and 1 (14%) improved 2 American Spinal Injury Association Impairment Scale Grades. Increased complications developed in SCI than non-SCI cases (mean, 2.0 vs. 0.1 complications; P=0.02). Bony fusion occurred in 26/28 patients (93%) after a median of 7.2 months (interquartile range, 6 to 15 mo). Ten patients (34%) returned to their baseline sport and 9 (31%) to lower-level activities.

CONCLUSIONS

The incidence of sports-related CSI requiring surgery is low with differences in age/sex, sport, and injury patterns. Older males with hyperflexion/axial loading injuries in contact sports were at greatest risk of SCI, complications, and permanent disability. Prevention campaigns, education on proper tackling techniques, and neck strength training are required in sports at high risk of hyperflexion/axial loading injury.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Characterization of head impact exposure in boys' youth ice hockey

Ice hockey has one of the highest concussion rates among youth sports. Sensor technology has been implemented in contact and collision sports to inform the frequency and severity of head impacts experienced on-ice. However, existing studies have utilized helmet-mounted sensors with limited accuracy. The objective of this study was to characterize head kinematics of contact events in a sample of youth boys' hockey players using a validated instrumented mouthpiece with improved accuracy. Head kinematics from 892 video-verified events were recorded from 18 athletes across 127 sessions. Median peak resultant linear acceleration, rotational velocity, and rotational acceleration of video-verified events were 7.4 g, 7.7 rad/s, and 576 rad/s², respectively. Contact events occurred at a higher rate in games (2.48 per game) than practices (1.30 per practice). Scenarios involving head contact had higher peak kinematics than those without head contact. This study improves our understanding of head kinematics in boys' youth hockey.