Ask the Doctors

Dear Doctor: My granddaughter plays soccer, and I've long been worried about the risk of concussion. Now I read that they last longer in girls. Why?

Dear Reader: This is a worry to which I can most definitely relate. My daughter is an aggressive soccer player and sometimes attempts to head balls during games. While I want her to do well in the sport, I worry about her risk of concussions. These head injuries can occur from a direct blow, such as when the head hits a soccer ball, or from a hit to the body in which the head is jarred.

One recent study assessed the effects on middle school and high school athletes -- patients of a sports medicine practice in southern New Jersey -- who had sustained a concussion in the years 2011 through 2013. The physician researchers assessed whether the athletes had a history of headaches, learning disabilities or mental illness, and whether they had suffered a loss of consciousness or problems with memory after the concussion. They also measured the athletes' symptom score (impact score) to assess the severity of the concussion and evaluated the length of days the athletes had symptoms after the head injury.

On the initial impact score, the 102 female athletes had a slightly higher score (17) than their 110 male counterparts (14). The male athletes had the greatest number of concussions from football, while the female athletes had the greatest proportion from soccer.

What was most striking about this study was the length of time it took for the athletes to recover to the baseline status. In the males, the median time was 11 days, while for females it was 28 days.

Another recent study, involving 2,004 high school students, compiled concussion data from 147 high schools from 26 states between 2011 and 2014. Again, the predominant causes among the male and female students were football and soccer, respectively. Overall, male athletes were more likely than female athletes to recover within one week; female athletes were more likely to take longer than 19 days. Player-to-player contact was the most common mechanism of injury for all sports. But, in soccer specifically, while 70 percent of male concussions were from player-to-player contact, only 40.6 percent of female concussions were from such contact. For females, 46 percent were from head-to-ball to contact.

A 2010 study with 215 males and females with concussions did not show any gender differences among athletes who continued to have symptoms after 90 days, but it did show that among the males, 16.3 percent recovered in one week, compared to 7.4 percent of the women.

It has been hypothesized that concussions last longer in females because they generally have decreased musculature in the neck compared to males. This may create less ability to absorb shock, leading to a greater acceleration of the brain within the skull. Other contributors may be the higher rates of headaches, depression and anxiety in adolescent females compared to males, which may contribute to a prolonged recovery from a concussion.

I wouldn't discourage your granddaughter, nor my own daughter, from playing soccer -- it's a fun sport. But it wouldn't be a bad idea for us to get them a tennis racquet for their next birthday.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

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