著者

Ryo Ogaki Miki Nariai Gento Otake Ayane Ogura Taiki Murakami Masahiro Takemura

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202117, (Released:2022-04-15)

参考文献数

18

被引用文献数

2

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A high risk of ankle injury is associated with rugby; however, current epidemiological data on rugby-related ankle injuries are limited to specific age and competition levels. This study aimed to clarify the epidemiological characteristics of ankle sprains by longitudinally investigating their incidence, severity, and burden in men's collegiate rugby. Ankle sprains that occurred during rugby matches and training in 128 male collegiate rugby players were investigated across three seasons (2017 – 2019). The incidence of ankle sprain was 1.21 injuries/1000 player-hours (PHs). The risk of occurrence during matches (18.18 injuries/1000 PHs) was 25.6 times higher than that during training (0.71 injuries/1000 PHs). The mean severity of ankle sprain was 24.7 days. The injury burden tended to be higher in the match season than in the training season. The main injury mechanisms were thought to be related to contact play and stepping (non-contact play). In addition, a high rate of initial sprains was observed in this study. Ankle sprain prevention is important in collegiate rugby players.

著者

Ryo Ogaki Gento Otake Satoko Nakane Yukiko Kosasa Yosuke Kanno Ayane Ogura Masahiro Takemura

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.9, no.5, pp.223-233, 2020-09-25 (Released:2020-09-16)

参考文献数

55

被引用文献数

2

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To the best of our knowledge, most previous studies regarding the epidemiology of injuries in rugby union (rugby) players have focused on professional players. Therefore, data on injuries in collegiate rugby players in Japan is limited. The purpose of this study was to conduct a prospective injury survey of Japanese male collegiate rugby players over several years and to analyze the injuries that occurred during matches and training according to field position, type of injury, and mechanism of injury. This prospective study initially registered 128 rugby players from one university club. The occurrence of injuries was recorded by athletic trainers during the rugby seasons between 2017 and 2019. The total injury rate (IR) was 7.26 injuries/1000 player-hours (1000 PHs). The match IR (122.73 injuries/1000 PHs) was almost 31.9 times higher than the training IR (3.84 injuries/1000 PHs). Ankle sprains/ligament injuries (17.7%; 1.28 injuries/1000 PHs) were the most common injuries, in addition to acromioclavicular joint injuries in forwards and hamstring strain injuries in backs. The most common injury mechanism was tackling (16.4%). Injury characteristics differed according to field position; therefore, preventive measures according to field position are necessary. Moreover, the high number of tackle injuries suggests that improved tackle skills would help reduce injuries. The IR among Japanese collegiate rugby players was higher than that reported previously. Injury prevention training for collegiate players is necessary to reduce the number of injuries.

著者

Keita Suzuki Satoshi Nagai Koichi Iwai Ryo Ogaki Takuo Furukawa Masahiro Takemura

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.201925, (Released:2020-04-06)

参考文献数

31

被引用文献数

2

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The present study aimed to determine the mechanisms of mild cervical injuries caused by tackling in a rugby union. This study enrolled 137 male players from a Japanese collegiate rugby union club during the 2009–2013 seasons. Twenty-nine (53.7%) of 54 incidents leading to mild cervical injury were identified from match video records and injury data that were reported under the definition of medical attention. In addition, all tackles by players in the same match in which they sustained cervical injury were extracted as a control cohort. All tackles were coded according to eleven characteristics of three tackle phases. Twenty-one tackles were the main events leading to mild cervical injury. The likelihood of tackler-associated mild cervical injuries was significantly higher when tacklers had no time to face forward at the offside line before tackle situations, tackles with incorrect tackler head positions, and not using arms after initial contact. These results suggest that further investigation is needed to determine specific tackling characteristics considering the three tackle phases and their combined effects.

著者

Keita Suzuki Satoshi Nagai Ryo Ogaki Koichi Iwai Takuo Furukawa Shumpei Miyakawa Masahiro Takemura

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.8, no.2, pp.79-88, 2019-03-25 (Released:2019-03-16)

参考文献数

28

被引用文献数

3

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The purpose of this study was to clarify the tackling characteristics of tacklers relationship causing concussion based on match video records in the collegiate rugby union. Twenty-three tackling situations leading to concussion were identified based on injury data and video records. Additionally, 94 tackling situations in which concussion did not occur were extracted from the same matches. Overall, one hundred and seventeen tackling situations were analyzed in detail, and categorized into three tackle phases and outcomes. Logistic regression analysis was performed to clarify which tackling characteristics in the tackler relationship had a higher chance of concussion. The chance of concussion occurring to a tackler was significantly higher for collision tackle (odds ratio [OR] 84.00, 95% CI 8.27–853.11), making initial contact with tackler’s head/neck (OR 23.47, 95% CI 4.80–114.71), no arm usage by tackler (OR 3.54, 95% CI 1.23–10.20) and tackle break by ball-carrier (OR 5.76, 95% CI 1.67–19.85). Conversely, tacklers were significantly less likely to suffer concussion when the ball-carrier performed a side step before initial contact (OR 0.11, 95% CI 0.01–0.85). In conclusion, tackles leading to concussion were related to various factors in the time period before and after tackle as well as in the moment of tackle. The results of this study suggest that further research needs to be done, given the relationship between each tackling characteristic. Moreover, we consider that players and coaching staff should improve tackle skill safety by clarifying the common contributing factors to both suffering concussion and tackle performance.

著者

Satoshi SHIBATA Masahiro TAKEMURA Shumpei MIYAKAWA

出版者

Japanese Society of Physical Therapy

雑誌

Physical Therapy Research (ISSN:21898448)

巻号頁・発行日

vol.21, no.2, pp.44-52, 2018-12-20 (Released:2018-12-20)

参考文献数

44

被引用文献数

14

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Background: Neurocognitive function may be a risk factor for anterior cruciate ligament (ACL) injury by changing neuromuscular control such as muscle activities. However, the effect of differences in neurocognitive function on biomechanics and neuromuscular control related to ACL injury risk is not clear. The purpose of this study was to examine the effect of differences in neurocognitive function on biomechanics and neuromuscular control during an unanticipated side-step cutting motion. Method: The subjects were 15 collegiate female athletes who were divided into two groups using the Symbol Digit Modalities Test (SDMT). The experimental task was an unanticipated side-step cutting motion from a 30 cm high box. We calculated joint angles and moments using a 3-dimensional motion analysis system from the dominant leg, and measured muscle activities using a surface electromyography. We calculated the co-contraction ratio (CCR) as relative muscle activity of the quadriceps to the hamstring. Results: As a result, subjects with a lower SDMT score had significantly increased quadriceps activity before and after ground contact and decreased CCR only after ground contact. Conclusion: In the lower SDMT score group, the quadriceps showed stronger muscle activity than the hamstring during an unanticipated side-step cutting motion. This dominant quadriceps muscle activity has been reported to increase the load on the ACL, and there was a possibility of increasing the risk of the ACL injury. Considering these factors, subjects with lower neurocognitive function could have a high risk of ACL injury due to alterations in muscle activities surrounding the knee.