Incidence of Sport Injuries in the Manchester 2019 World Taekwondo Championships: A Prospective Study of 936 Athletes from 145 Countries.

We aimed to describe injury incidence and patterns at the 2019 World Taekwondo Championships (WTC), and to compare them with those of previous WTCs, based on new World Taekwondo (WT) competition rules, medical codes, and the Protector and Scoring System (PSS). This prospective cohort study utilized data obtained through the WT Injury Surveillance System. All athletes with injuries were evaluated by on-site sports medicine specialists, and ultrasonography was used to assess all musculoskeletal injuries. Of 936 athletes, 60 injuries were recorded (6.4 injuries/100 athletes, 95% confidence intervals [CI]: 4.8-8.0), and 4.5% (n = 42) sustained at least one injury. Males had a higher risk of sustaining injuries than females (incidence rate ratio: 1.57; 95% CI: 0.89-2.76). The most common sites, type, and mechanism were lower extremities (n = 26, 43.33%), contusion/hematoma/bruises (n = 33, 55.0%), and contact with another athlete (n = 50, 83.33%). Overall, the injury patterns associated with the mechanism of injury were similar in both the 2019 and 2017 WTCs. Refined WT competition rules and a re-established PSS at the 2019 WTC reduced the overall and severe injury incidence. Our findings can help revise Taekwondo competition rules, enhance protective equipment, optimize on-site venue medical systems, and develop injury prevention projects.

Mechanisms of Sports Concussion in Taekwondo: A Systematic Video Analysis of Seven Cases.

Sports-related traumatic brain injuries are the most common injury in adolescents and young adults due to recurrent concussion experiences and head shock. Therefore, this study was designed to describe player characteristics and situational factors associated with concussions in the World Taekwondo Championships using systematic video analysis. Athlete injury data were collected using a web-based injury surveillance system at the World Taekwondo Championships organized by World Taekwondo from 2017 to 2019. Seven video footage were independently analyzed by four analysts using a modified Heads-Up Checklist. Descriptive statistical analysis was used. The incidence of concussion was 3.21 per 1000 games. Most players with concussions were shorter than their opponents, and most concussions were caused by a roundhouse kick on the front of the face. Regarding the acceleration direction of the head after the impact, transverse and multiplane directions were the most common. Most players with a concussion have used a closed stance and did not use blocking techniques during the defense. The rate of concussions caused by penalties was 42.9%. Based on our findings, no other injury mechanisms, except for direct blows to the head, were observed. Therefore, education on the risk and symptoms of concussion, the appropriate management and blocking techniques should be emphasized in TKD-S to reduce incidence of concussion.

Epidemiological study of post-traumatic ankle osteoarthritis after ankle sprain in 195,393 individuals over middle age using the National Health Insurance Database: A retrospective design.

OBJECTIVES: This study aimed to determine the risk of ankle OA onset after an incidence of sprain, relative to the risk of onset in healthy population, and to investigate the effect of gender, age, BMI, and exercise on the development of ankle OA after sprain. DESIGN: Retrospective cohort study. METHODS: Using a sample cohort dataset from 2002 to 2013 provided by the Korean National Health Insurance Sharing Service, we calculated the mean survival time and cumulative incidence rate in sprained and healthy populations using Kaplan-Meier analysis. A Cox proportional hazards model was used to analyze the adjusted hazard ratio (HR) of sprain for the development of OA with 95% confidence intervals (CIs). Adjusted HRs of gender, age, BMI, and exercise (yes/no) were analyzed in the sprained group. RESULTS: Among the selected population of 195,393 individuals, 40,876 (20.9%) were diagnosed with an ankle sprain, and 1543 (3.85%) of those individuals developed ankle OA. Of the 154,517 healthy individuals (79.1%), 4062 (2.66%) cases had progressed to OA. The sprained group had 46% (HR, 1.46; 95% CI, 1.38-1.55) greater rate of progression to ankle OA than did healthy individuals. In the sprain group, individuals who were female, obese, and overweight had 40% (HR, 1.40; 95% CI, 1.26-1.55), 43% (HR, 1.43; 95% CI, 1.12-1.82), and 22% (HR, 1.22; 95% CI, 1.10-1.35) higher incidence to develop ankle OA, respectively, compared to those who were male, underweight and normal. CONCLUSIONS: This study found that ankle sprain was a significant risk factor for a diagnosis of early OA. Female gender and high BMI increased the incidence of ankle OA after sprain.

Injury and Illness in World Taekwondo Junior Athletes: An Epidemiological Study.

Taekwondo has been reported to be one of the most injurious sports in the summer Olympics, however, there is a dearth of data about injury profiles for junior athletes. Therefore, we aimed to identify the incidence and profiles of the injuries and illnesses that occurred during the 2018 World Taekwondo Junior Championships and recorded using an online system. Among the 889 athletes, 67 injuries and four illnesses were reported, corresponding to an overall clinical incidence of 7.5 injuries (95% confidence interval [CI]: 5.7-9.3) and 0.5 illnesses (0.1-0.9) per 100 athletes. The most frequent injuries were lower extremity injuries (n = 33, 3.71% of all athletes), mostly in the foot/toe (n = 11, 1.2% of athletes), followed by head and trunk injuries, mostly in the face (n = 14, 1.6% of athletes), and upper extremity injuries, mostly in the fingers (n = 6, 0.7% of athlete). Contusions (n = 37, 4.2% of athlete) were the most frequent injury type, followed by ligament ruptures/sprains and laceration. The most common injury mechanism was contact during an opponent attack (n = 51, 5.7% of athlete). Three mild concussions none resulted in time loss (none required hospital transfer or had prolonged recovery). The respiratory system was the most affected by illness, with pain and fever as symptoms. Environmental factors were the most common cause of illness. This study shows that 7.5 per 100 athletes (38.5/1000 athlete-exposures and 6.9/1000 min-exposures) had new or recurrent injuries, whereas 0.5 per 100 athletes experienced illness. In conclusion, the data shows male athletes reported more injuries than females and the most common cause of injury was due to contact between athletes. Contusions, ligament rupture/sprains, laceration and fractures to the lower extremities, head, and trunk were the most common injury. Knowing these injury profiles of junior taekwondo athletes can help taekwondo stakeholders, especially medical staff to prepare accordingly to ensure the safety of the athletes.

Sports Injuries and Illnesses After Implementation of the Web-Based Surveillance System in World Taekwondo.

CONTEXT: Taekwondo epidemiology studies have been in short supply since the rule changes introduced by World Taekwondo in 2017. OBJECTIVE: To describe injury and illness patterns at the 2017 World Taekwondo Championships (WTC) in Muju, South Korea, after the implementation of the web-based surveillance system by World Taekwondo. DESIGN: Prospective cohort study. SETTING: All injuries and illnesses were recorded during the 2017 WTC using a web-based system developed by the International Olympic Committee. PATIENTS OR OTHER PARTICIPANTS: A total of 971 athletes who participated in the 2017 WTC. MAIN OUTCOME MEASURE(S): Profiles and mechanisms of injury and illness in the 2017 WTC. RESULTS: We analyzed a total of 131 injuries and 26 illnesses, corresponding to an overall clinical incidence of 13.5 (95% CI = 11.2, 15.8) injuries and 2.7 (95% CI = 1.6 3.7) illnesses per 100 athletes and an overall incidence rate of 19.3 (95% CI = 16.0, 22.6) injuries and 3.8 (95% CI = 2.4, 5.3) illnesses per 1000 athlete-days. Most injuries occurred in the lower extremities (n = 61, 46.6%), and knee injuries were most frequent (n = 26, 19.8%). Among head and trunk injuries (n = 39, 29.8%), face injuries (n = 32, 24.4%) were most common, whereas among upper extremity injuries (n = 31, 23.7%), finger injuries (n = 8, 6.1%) were seen most often. Contusions (n = 44, 33.6%) were the most frequent injury type, followed by fractures and ligamentous ruptures or sprains. The most common injury mechanism was contact with another athlete (n = 97, 74.0%), whereas the least common was concussion (n = 5). The major affected system was the respiratory system (n = 11, 42.3%), with major symptoms being pain (n = 11, 42.3%) and fever (n = 7, 26.9%). Environmental factors were the most typical cause of illness (n = 15, 57.7%). CONCLUSIONS: The web-based surveillance system used at the 2017 WTC revealed that 13.5 per 100 athletes (77.8/1000 athlete-exposures, 13.9/1000 minute-exposures) had new or recurrent injuries, whereas 2.7 per 100 athletes became ill.

Investigating the influence of Taekwondo body protectors size on shock absorption.

OBJECTIVE: This study aims to compare and analyze the difference of impact force attenuation according to size and impact location on a Taekwondo body protector. METHODS: Body protectors sized 1 to 5, were impact tested by equipment based on the specifications in the European standard manual (EN 13277-1, 3). The impactor release heights were set to match impact energies of 3 and 15 J. The impactor was made from a 2.5 kg cylindrically cut piece of aluminum. Each body protector was impacted 10 times at the two impact energies and two locations. The differences in performance for each body protector size were compared using a two-way analysis of variance with a significance level of p< 005. The effect sizes were investigated using a partial eta squared value (η2). RESULTS: The significant mean differences between the body protector size and impact area (p< 005) and the average impact time of impact strengths 3 and 15 J were 0.0017 and 0.0012 s, respectively In addition, when an impact strength of 15 J was applied, the maximum resulting impact force exceeded 2000 N for both locations on all sizes. Furthermore, at an impact strength of 3 J size 3 significantly reduced the impact force more than the other sizes; however, size 1 showed the greatest shock absorption at an impact of 15 J. CONCLUSION: The results of this study show that the shock absorption of body protectors does not increase according to size; i.e., a larger body protector does not reduce the impact load more effectively. To improve safety performance, we recommend a maximum impact force of 2000 N or less for all body protectors.

Injuries in Korean Elite Taekwondo Athletes: A Prospective Study.

This prospective cohort study aimed to identify the incidence and characteristics of Taekwondo-related injuries according to age, sex, and event type (i.e., practice or competition) based on a web-based injury surveillance system (ISS) with a follow-up period of 12 months. A total of 285 members of the Korea Taekwondo Association who competed in the 2016 season participated. Injury incidence rates (IRs) were calculated per 1000 athlete-exposures (AEs). Injury rate ratios (RRs) with 95% confidence intervals were calculated and compared regarding age, sex, and event type. During the season, 336 injuries were reported, resulting in a rate of 6.31/1000 AEs. The most common location, type, and mechanism of injury in Taekwondo athletes were the foot/ankle, ligament sprain, and contact with another player, respectively. The overall injury IRs associated with Taekwondo practicing and competition were 4.79/1000 AEs and 24.86/1000 AEs, respectively. The overall injury RR related to both practice and competition was higher in youth athletes than in adult athletes. However, adult athletes were more likely to sustain more severe injuries. Korean elite Taekwondo athletes were commonly exposed to injury, especially youth and female athletes. Therefore, continuation of the ISS suggests the development of interventions for preventing injuries sustained by Taekwondo athletes.

Safety Evaluation of Protective Equipment for the Forearm, Shin, Hand and Foot in Taekwondo.

The objective of the study was to evaluate and compare different brands of forearm, shin, hand and foot protective equipment used in Taekwondo. The most popular brands of large forearm, shin, hand and foot protectors (D®, A®, K ®), approved by the World Taekwondo and Korean Taekwondo Association, were examined. A drop test was used to test the protective equipment using impact levels of 3J, 9J, 12J and 15J for the forearm and shin guards, and 3J and 9J for the hand and foot protectors. The protective equipment was hit ten times from each of the designated drop heights. The drop test is described in the European standards manual of protective equipment for martial arts (SRPS EN 13277-2). The maximum force (MF) and impulse were lowest for brand K® (2610.3 ± 1474.1 N), and brand A® (9.6 ± 3.1 Ns), respectively, for the forearm guards; for brand A® (2053.4 ± 1267.1 N) and brand K® (9.8 ± 3.5 Ns), respectively, for the shin guards; for brand K® (4486.5 ± 1718.4 N), and brand A® (6.3 ± 1.1 Ns), respectively for the hand protectors; and for brand A® (3733.7 ± 2465.3 N), and brand D® (6.8 ± 0.6 Ns), respectively, for the foot protectors. For the forearm guard brand and impact level, there was a significant interaction effect for the MF (F=42.44, η2=.677, p <0.001) and impulse (F = 33.97, η2 = 0.626, p <0.001). Based on the MF, brand K® performed the best for the forearm guards and hand protectors, and brand A®, for the shin guards and foot protectors. The best results for the impulse were for brand A® (forearm guards and hand protectors), brand K® (shin guards) and brand D® (foot protectors).

Evidence-Based Cutoff Threshold Values from Receiver Operating Characteristic Curve Analysis for Knee Osteoarthritis in the 50-Year-Old Korean Population: Analysis of Big Data from the National Health Insurance Sharing Service.

We aimed to investigate the characteristics of patients with osteoarthritis (OA), using the data of all Koreans registered in the National Health Insurance Sharing Service Database (NHISS DB), and to provide ideal alternative cutoff thresholds for alleviating OA symptoms. Patients with OA (codes M17 and M17.1-M17.9 in the Korean Standard Classification of Disease and Causes of Death) were analyzed using SAS software. Optimal cutoff thresholds were determined using receiver operating characteristic curve analysis. The 50-year age group was the most OA pathogenic group (among 40~70 years, n = 2088). All exercise types affected the change of body mass index (p < 0.05) and the sex difference in blood pressure (BP) (p < 0.01). All types of exercise positively affected the loss of waist circumference and the balance test (standing time on one leg in seconds) (p < 0.01). The cutoff threshold for the time in seconds from standing up from a chair to walking 3 m and returning to the same chair was 8.25 (80% sensitivity and 100% specificity). By using the exercise modalities, categorized multiple variables, and the cutoff threshold, an optimal alternative exercise program can be designed for alleviating OA symptoms in the 50-year age group.

Rotational and linear head accelerations from taekwondo kicks and punches.

The purpose was to compare rotational and linear head accelerations as a result of taekwondo kicks and punches. Taekwondo athletes executed five repetitions of the turning kick, spinning hook kick, hook punch, straight punch, and jab punch to a Hybrid III Crash Test Dummy head-neck complex. A tri-axial accelerometer and an angular rate sensor were mounted inside the Hybrid III head to measure resultant linear (RLA) and rotational accelerations. The Hybrid III was fixed to a height-adjustable frame and fitted with protective taekwondo headgear. Dummy head height was positioned to each participant's standing height. Acceleration data were processed in accordance with SAE J211-1.There was no significant multivariate difference in RLA but the effect was not clear. Univariate follow-up analysis showed a significant difference in RLA but the effect was also not clear. There was no difference in rotational acceleration. The highest RLA and rotational acceleration were produced, in order, by the turning kick, hook kick, hook punch, straight punch, and jab. These data are clinically important as they provide a better understanding of the biomechanical injury measures and support for improved headgear testing methodology.

Pilot study comparing changes in postural control after training using a video game balance board program and 2 standard activity-based balance intervention programs.

OBJECTIVE: To compare the impacts of Tai Chi, a standard balance exercise program, and a video game balance board program on postural control and perceived falls risk. DESIGN: Randomized controlled trial. SETTING: Research laboratory. PARTICIPANTS: Independent seniors (N=40; 72.5±8.40) began the training, 27 completed. INTERVENTIONS: Tai Chi, a standard balance exercise program, and a video game balance board program. MAIN OUTCOME MEASURES: The following were used as measures: Timed Up & Go, One-Leg Stance, functional reach, Tinetti Performance Oriented Mobility Assessment, force plate center of pressure (COP) and time to boundary, dynamic posturography (DP), Falls Risk for Older People-Community Setting, and Falls Efficacy Scale. RESULTS: No significant differences were seen between groups for any outcome measures at baseline, nor were significant time or group × time differences for any field test or questionnaire. No group × time differences were seen for any COP measures; however, significant time differences were seen for total COP, 3 of 4 anterior/posterior displacement and both velocity, and 1 displacement and 1 velocity medial/lateral measure across time for the entire sample. For DP, significant improvements in the overall score (dynamic movement analysis score), and in 2 of the 3 linear and angular measures were seen for the sample. CONCLUSIONS: The video game balance board program, which can be performed at home, was as effective as Tai Chi and the standard balance exercise program in improving postural control and balance dictated by the force plate postural sway and DP measures. This finding may have implications for exercise adherence because the at-home nature of the intervention eliminates many obstacles to exercise training.