Acute Subdural Hematoma in High School Rugby Players in Japan: The Importance of Playing Experience for Injury Prevention.

OBJECTIVES: Acute subdural hematoma (ASDH) is known to be devasting sport-related head injury but it is relatively rare in rugby compared with other contact sports. Certain cases of ASDH have happened in high school rugby players in Japan. To prevent them from the injury we report a background of the players. METHODS: Data of high school rugby players who suffered ASDH were extracted from injury reports in the Japan Rugby Football Union between April 2004 and March 2020. The number of injured players, diagnosis on the report, school year, phase of play where the injury occurred, and playing career were analyzed. RESULTS: There were 30 cases of ASDH including 16 cases in the first year, 9 in the second year, and 5 in the third year of playing. Phase of play was mainly being tackled in 11 (37%), and tackling in 13 (43%). Novice players, defined as a player having less playing experience of rugby during junior high school, accounted for 77% of phase of tackling, 82% of being tackled. First year novice players accounted for 100% of phase of being tackled. Outcome within 6 months after injury was recovery in 14, morbidity in 6, mortality in 2, and unknown in 8. CONCLUSIONS: Playing experience in high school rugby players should be considered as an important factor for prevention of ASDH-in particular, phase of being tackled is riskier than that of tackling for first year novice players.

Correlates to traumatic brain injury in nonhuman primates.

BACKGROUND: Traumatic brain injury (TBI) is a major health problem, both in terms of the economic cost to society and the survivor's quality of life. The development of devices to protect against TBI requires criteria that relate observed injury to measurements of head kinematics. The objective of this study is to find the best statistical correlates to impact-induced TBI in nonhuman primates using a qualified, self-consistent set of historical kinematic and TBI data from impact tests on nonhuman primates. METHODS: A database was constructed and qualified from historical head impact tests on nonhuman primates. Multivariate logistic regression analysis with backwards stepwise elimination was performed. Variables considered are the peak rotational acceleration (Omegamax), the peak linear acceleration (Amax), and the number of impacts (N). RESULTS: Bivariate combinations of angular acceleration and the number of impacts are the best correlates to all modes of TBI considered, i.e., concussion, subarachnoid hemorrhage, brain contusion, and subdural hematoma. For a nonhuman primate with 100-g brain mass, the criteria that the probability of TBI is less than 10% by injury mode are:Concussion: OmegamaxN(0.84) < 70 krad/s/s SAH: OmegamaxN(0.70) < 160 krad/s/s Contusion: Omegamax N(0.35) < 160 krad/s/s SDH: Omegamax N(0.60) < 280 krad/s/s CONCLUSIONS: Based on this dataset, the best statistically based risk factor for all modes of TBI in nonhuman primates is the bivariate combination of rotational acceleration and number of impacts.

Considerations in the evaluation of haemophilia patients for short-term prophylactic therapy: a paediatric and adult case study.

The long-term prophylactic administration of clotting factor concentrate in patients with haemophilia reduces bleeding events, slows joint deterioration, and improves quality of life. Prophylaxis can also be effective when used short-term to prevent or reduce bleeding associated with trauma, surgery, and athletic activities. While clinical trials are needed to establish the optimal length of prophylaxis following injury, several weeks and possibly months of treatment may be needed. Discontinuing therapy prematurely can result in rebleeding in the injured area.