The potential for brain injury on selected surfaces used by cheerleaders

Catastrophic Sports Injuries: Causation and Prevention

➤ Catastrophic injuries in U.S. high school and college athletes are rare but devastating injuries.➤ Catastrophic sports injuries are classified as either traumatic, caused by direct contact during sports participation, or nontraumatic, associated with exertion while participating in a sport.➤ Football is associated with the greatest number of traumatic and nontraumatic catastrophic injuries for male athletes, whereas cheerleading has the highest number of traumatic catastrophic injuries and basketball has the highest number of nontraumatic catastrophic injuries for female athletes.➤ The incidence of traumatic catastrophic injuries for all sports has declined over the past 40 years, due to effective rule changes, especially in football, pole-vaulting, cheerleading, ice hockey, and rugby. Further research is necessary to reduce the incidence of structural brain injury in contact sports such as football.➤ The incidence of nontraumatic catastrophic injuries has increased over the last 40 years and requires additional research and preventive measures. Avoiding overexertion during training, confirming sickle cell trait status in high school athletes during the preparticipation physical examination, and developing cost-effective screening tools for cardiac abnormalities are critical next steps.

Understanding the Cheerleader as an Orthopaedic Patient: An Evidence-Based Review of the Literature

Cheerleading is a highly popular youth sport in the United States and has been increasingly recognized in recent years for its athleticism and competitive nature. The sport has changed dramatically since its inception. When the sport of cheerleading was first developed, its primary purpose was to entertain crowds and support other athletes. Today, cheerleaders are competitive athletes themselves. Cheerleaders, most of whom are in the pediatric age group, and their parents commonly approach orthopaedic surgeons and sports medicine physicians with questions regarding the risks associated with participation in the sport. Appropriate clinical guidance is especially important for athletes returning to the sport after an injury. However, unlike other popular sports (eg, football, basketball, and volleyball), the intricacies of cheerleading are not well-known to those outside the sport, including many health care providers. Previous studies have reported on the epidemiological patterns of injuries associated with cheerleading and how such aesthetic sports affect the body, finding that fractures and concussions are prevalent and that catastrophic injuries are more common than in most other sports. Here, we provide an evidence-based discussion of 10 pertinent topics regarding cheerleading and its risks to the musculoskeletal system. The purpose of this review is to provide a comprehensive resource for orthopaedic surgeons and sports medicine physicians who care for these athletes.

EFFECTS OF SURFACE ON TRIPLE HOP DISTANCE AND KINEMATICS

Background

The single leg triple hop (SLTH) test is often utilized by rehabilitation practitioners as a functional performance measure in a variety of patient groups. Accuracy and consistency are important when measuring the patient progress and recovery. Administering the SLTH test on different surfaces, consistent with the patient's sport, may affect the hop distances and movement biomechanics.

Purpose

The purpose of this study was to examine the effects of court and turf surfaces on the hop distance, limb symmetry index (LSI), and lower extremity kinematics of a SLTH test.

Methods

Recreationally active female participants (n=11, height 163.8 ± 7.1cm, mass 63.1 ± 7.1kg, age 18.9 ± 0.9yrs), without injury, volunteered to participate in the study. Three maximal effort SLTH test trials on two different surfaces (court, synthetic turf) were collected and analyzed using 3D motion analysis techniques. Outcome variables included SLTH test distances and LSI values and sagittal plane kinematics including trunk, hip, knee and ankle range of motion (ROM) during the last two landings of each SLTH test trial. The second landing involves an absorption phase and propulsion phase in contrast to the final landing which involves absorption and final balance on the single leg. Paired t-tests were used to determine differences between surfaces in hop distance and LSI values. Two-way repeated measures ANOVA were used to determine differences between surfaces in kinematic variables.

Results

The total SLTH test distance was not statistically different between the court (4.11 ± 0.47m) and turf (4.03 ± 0.42m, p=0.47) surfaces. LSI for the court surface was 100.8 ± 3.0% compared to 99.7 ± 3.0% for turf surface, which was not statistically different (p=0.30). Knee flexion ROM was significantly less (p=0.04) on the turf compared to the court surface during the second landing. Ankle flexion range of motion was also significantly less (p=0.03) during the second landing on turf compared to court.

Conclusions

Type of surface influenced landing kinematics but not total SLTH test distance. When evaluating the quality of landings during a SLTH test, it may be warranted to observe each type of landing and the type of surface used during single leg tests.

Level of Evidence

2.

A comparison of floor surfaces for injury prevention in care settings: impact forces and horizontal pulling force required to move wheeled equipment

Shock-absorbing flooring is one potential solution to prevent fall-related injuries. No standards exist to characterize shock-absorbing healthcare flooring. This study explores two mechanical tests for impact force reduction and horizontal force required to move wheeled objects. An appropriately designed rubber underlay can reduce peak impact by 25% compared with 1% with standard vinyl.

INTRODUCTION

Severe falls often occur in hospitals and care homes. Shock-absorbing flooring is one potential solution to prevent fall-related injuries; however, no standards exist for characterizing flooring as an injury prevention measure. Shock-absorbing flooring use in high-risk settings may influence both patients (injury-saving potential) and staff (manoeuvring equipment). We aimed to explore two tests to characterize floors, to determine shock absorbency and horizontal pulling force required to move wheeled objects.

METHODS

Mechanical testing was performed according to the Canadian Standards Association Z325 Hip Protectors document. This test was developed for hip protectors but is applicable to compliant surfaces that form part of the floor. Tests were performed on commercially available floor materials (suitable for care settings) to assess the force required to initiate movement of a wheeled object across the floor. We explored the relationships between horizontal force required to pull wheeled objects, impact force, floor thickness, and core material.

RESULTS

Considerable differences were identified between floor samples in their ability to reduce the peak impact force (range 0.7-25%). A peak force reduction of up to 25% can be achieved with a specially designed rubber underlay. Horizontal pulling force increased with floor thickness but was lower for rubber floors. There was no direct relationship between impact attenuation and horizontal pulling force. Whilst thickness and core material explain some variations (66.5% for wheel movement; 82.3% for impact), other unmeasured factors clearly influence floor performance.

CONCLUSIONS

These results can inform the development of flooring and the establishment of standards needed to underpin practice, research, and development in this field.

Cheerleading injuries in children: What can be learned?

Introduction

Cheerleading has gradually become more popular in Canada and represents an accessible way for youth to be physically active.

Objective

To determine the differences in the injuries encountered by cheerleaders according to their age, in order to propose safety guidelines that take into account the developmental stages of children.

Method

Retrospective database review of cheerleading injuries extracted from the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) database between 1990 and 2010. The injuries were compared by age group (5 to 11 versus 12 to 19) according to their sex, mechanism of injury and injury severity.

Results

Overall, in 20 years, there were 1496 cases of injuries documented secondary to cheerleading (median age 15, 4 (interquartile range [IQR]=2, 2) years); mostly females (1410 [94%]). Of that number, 101 cases were 5 to 11 years old (age group [AG]1), while 1385 were 12 to 19 (AG2). Participants in AG1 were found to have a higher proportion of moderate-to-severe injury (46.5% compared with 28.2% in AG2). The odds ratio of moderate/severe injury for AG1 compared with AG2 was found to be 2.217 (95% CI [1.472; 3.339]). No fatalities were known to have occurred.

Conclusion

Children's developmental stages affect their ability to participate in sports and the responses of their bodies to impact forces. Our findings concerning cheerleading injuries indicate that younger children (5 to 11 years old) are more likely to suffer moderate-to-severe injuries. Thus, on a local basis, the use of appropriate safety measures including appropriate flooring/safety mats and spotters to catch falling athletes should be mandatory.

Pediatric Cheerleading Injuries Treated in Emergency Departments in the United States

This study investigates the epidemiology of cheerleading injuries to children in the United States. Data were analyzed from the National Electronic Injury Surveillance System for children 5 through 18 years of age treated in US emergency departments for cheerleading injuries from 1990 through 2012. An estimated 497 095 children ages 5 to 18 years were treated in US emergency departments for a cheerleading injury during the 23-year study period, averaging 21 613 injured children per year. From 1990 to 2012, the annual cheerleading injury rate increased significantly by 189.1%; and from 2001 to 2012, the annual rate of cheerleading-related concussion/closed head injury increased significantly by 290.9%. Falls were the most common mechanism of injury (29.4%) and were more likely to lead to hospitalization (relative risk = 2.47; 95% confidence interval = 1.67-3.68) compared with other injury mechanisms. The rising number and rate of pediatric cheerleading injuries underscore the need for increased efforts to prevent these injuries.

Neck and spine injuries in Canadian cheerleaders: An increasing trend

BACKGROUND/PURPOSE

Cheerleading, now increasingly practiced in Canada, has a high propensity to cause traumatic neck and spine injuries. We aimed to evaluate the importance of neck and spine injuries in the practice of cheerleading and their occurrence mechanisms in order to propose preventive measures.

METHODS

A retrospective cohort study of cheerleading injuries extracted from the Canadian Hospitals Injury Reporting and Prevention Program database between 1990 and 2010 was performed.

RESULTS

Overall, there were 1496 cases of injuries documented secondary to cheerleading (median age 15, 4 (IQR=2, 2) years; 1410 women (94%)). Of those, 125 cases (8%) were neck and spine injuries. The most frequent injury was a sprain/strain (47%). More severe injuries included fractures (4%), muscle or tendon injury (3%), dislocation (1%), and nerve injury (1%). Over half of these injuries were caused by either falling from (26%) or basing/spotting a stunt from height (26%). Other mechanisms include being thrown/falling from a high toss (10%) and falling from a pyramid (8%). Of the 125 cases, 3 (2, 4%) were admitted to hospital.

CONCLUSIONS

Most neck and spine injuries were related to stunts. Although the proportion of serious injury is low, the increasing trend for the practice of cheerleading calls for preventive measures.

Simplification and transformation of ASTM F1292 measurement procedure for fall accident injury criteria

Protecting children from injuries caused by fall accidents from playground equipment is important. Therefore, measures toward minimizing the risk of fall accident injuries are required. The risk of injury can be evaluated using ASTM F1292. In this test, G-max and the HIC are used to estimate the risk of injury. However, the measurement procedure is too complicated for application to a large number of installed equipment. F1292 requires simplified by reducing the number of phases, even with a small risk of loss in accuracy. With this in mind, this study proposes a shortened measurement procedure and a transformation equation to estimate the risk as same as F1292. As the result of experiments, it was revealed that G-max and the HIC values for both procedures linearly increase with drop height. The differences in outcomes between the regression equations of the standardized procedure and those of the shortened procedure can be used as a correction value. They can be added to the value measured by the shortened procedure. This suggests that the combination of the shortened procedure and transformation equation would be equivalent to F1292, with the advantage of being more easily and efficiently applied to the evaluation of installed playground equipment.

What goes up must come down! A primary care approach to preventing injuries amongst highflying cheerleaders

PURPOSE

This article provides information regarding the most common nonlife-threatening and catastrophic injuries that occur during cheerleading, and describes the role of the nurse practitioner (NP) in managing patients who participate in cheerleading.

DATA SOURCES

Literature review of evidence-based research articles, epidemiological reports, and current guidelines.

CONCLUSIONS

Cheerleading is one of the most popular sports among adolescent females, and participation has increased rapidly in recent years. Rates of injury have also increased as the difficulty of this activity reaches new heights. Several factors such as body changes during puberty, societal pressures affecting nutrition, and lack of safety regulations place cheerleaders at risk for injury. Sprains/strains are the most common injury, and concussions are the most common traumatic injury. Injuries occur as a result of tumbling, stunting, falling, spotting, and unsafe practice surfaces.

IMPLICATIONS FOR PRACTICE

The role of the NP in injury prevention is to identify risk factors during preparticipation physicals, initiate conditioning and strength training routines, and implement safety measures during practices and competitions. The NP should also provide education and guidance to cheerleaders, parents, and coaches.

Cheerleading injuries: epidemiology and recommendations for prevention

Over the last 30 years, cheerleading has increased dramatically in popularity and has evolved from leading the crowd in cheers at sporting events into a competitive, year-round sport involving complex acrobatic stunts and tumbling. Consequently, cheerleading injuries have steadily increased over the years in both number and severity. Sprains and strains to the lower extremities are the most common injuries. Although the overall injury rate remains relatively low, cheerleading has accounted for approximately 66% of all catastrophic injuries in high school girl athletes over the past 25 years. Risk factors for injuries in cheerleading include higher BMI, previous injury, cheering on harder surfaces, performing stunts, and supervision by a coach with low level of training and experience. This policy statement describes the epidemiology of cheerleading injuries and provides recommendations for injury prevention.

Football helmet drop tests on different fields using an instrumented Hybrid III head

An instrumented Hybrid III head was placed in a Schutt ION 4D football helmet and dropped on different turfs to study field types and temperature on head responses. The head was dropped 0.91 and 1.83 m giving impacts of 4.2 and 6.0 m/s on nine different football fields (natural, Astroplay, Fieldturf, or Gameday turfs) at turf temperatures of -2.7 to 23.9 °C. Six repeat tests were conducted for each surface at 0.3 m (1') intervals. The Hybrid III was instrumented with triaxial accelerometers to determine head responses for the different playing surfaces. For the 0.91-m drops, peak head acceleration varied from 63.3 to 117.1 g and HIC(15) from 195 to 478 with the different playing surfaces. The lowest response was with Astroplay, followed by the engineered natural turf. Gameday and Fieldturf involved higher responses. The differences between surfaces decreased in the 1.83 m tests. The cold weather testing involved higher accelerations, HIC(15) and delta V for each surface. The helmet drop test used in this study provides a simple and convenient means of evaluating the compliance and energy absorption of football playing surfaces. The type and temperature of the playing surface influence head responses.

Epidemiology of cheerleading fall-related injuries in the United States

CONTEXT

Over the past several decades, cheerleaders have been performing fewer basic maneuvers and more gymnastic tumbling runs and stunts. As the difficulty of these maneuvers has increased, cheerleading injuries have also increased.

OBJECTIVE

To describe the epidemiology of cheerleading fall-related injuries by type of cheerleading team and event.

DESIGN

Prospective injury surveillance study.

SETTING

Participant exposure and injury data were collected from US cheerleading teams via the Cheerleading RIO (Reporting Information Online) surveillance tool.

PATIENTS OR OTHER PARTICIPANTS

Athletes from 412 enrolled cheerleading teams who participated in official, organized cheerleading practices, pep rallies, athletic events, or cheerleading competitions.

MAIN OUTCOME MEASURE(S)

The numbers and rates of cheerleading fall-related injuries during a 1-year period (2006-2007) are reported.

RESULTS

A total of 79 fall-related injuries were reported during the 1-year period. Most occurred during practice (85%, 67/79) and were sustained by high school cheerleaders (51%, 40/79). A stunt or pyramid was being attempted in 89% (70/79) of cases. Fall heights ranged from 1 to 11 ft (0.30-3.35 m) (mean = 4.7 + or - 2.0 ft [1.43 + or - 0.61 m]). Strains and sprains were the most common injuries (54%, 43/79), and 6% (5/79) of the injuries were concussions or closed head injuries. Of the 15 most serious injuries (concussions or closed head injuries, dislocations, fractures, and anterior cruciate ligament tears), 87% (13/15) were sustained while the cheerleader was performing on artificial turf, grass, a traditional foam floor, or a wood floor. The fall height ranged from 4 to 11 ft (1.22-1.52 m) for 87% of these cases (13/15).

CONCLUSIONS

Cheerleading-related falls may result in severe injuries and even death, although we report no deaths in the present study. The risk for serious injury increases as fall height increases or as the impact-absorbing capacity of the surfacing material decreases (or both).