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Warning from Nagano: increase of vulvar hematoma and/or lacerated injury caused by snowboarding.

BACKGROUND
On the basis of the number of women snowboarders whose vulvar injuries we have recently treated, we believe that the cases of vulvar hematoma and lacerated injuries caused by snowboarding have been increasing. To analyze the causal relation between snowboarding and vulvar injuries, we investigated how women were injured during snowboarding.


METHODS
During the last three ski-ing seasons at the five hospitals near the ski resorts in Nagano Prefecture, Japan, the clinical charts of all patients with vulvar injuries during snowboarding were reviewed for the number of patients treated, the condition of the patients at diagnosis, and the characteristics of vulvar injuries. All patients were also asked by phone about how their vulvar injury was caused during snowboarding.


RESULTS
The number of patients with vulvar injuries during the last three seasons was 16, 14, and 35, respectively. The types of vulvar injuries included hematoma in 33 (51%) patients, hematoma with lacerated injury in 17 (26%), and lacerated injury in the remaining 15 (23%). Of the 65 patients, 45 (69%) needed surgical treatment. Characteristically, 54 (88%) patients were injured when they tumbled onto the binding of the snowboard at the same time that one foot was left off the board and the binding was not turned down but left erect.


CONCLUSION
It is important for women snowboarders to realize that in snowboarding there are dangers that may cause vulvar injuries. The prevention of such injuries requires that the binding should be turned down when the foot is left off the board and that snowboarders should try not to tumble onto the board.