Lacrosse is one of the fastest-growing sports in the United States, with nearly 213,000 high school males and females participating during the 2018/19 academic year.

Dr. Amanda Esquivel
Dr. Amanda Esquivel

Unique from other sports, there are significant rule differences between the men’s and women’s games. Men’s lacrosse is considered a collision sport because it allows both body and stick-checking. Because of this, male protective equipment includes helmets with facemasks, pads, gloves, and mouthguards.

Women’s lacrosse does not allow purposeful collisions, with only controlled stick-checking. Personal protective measures for females only consist of eye protection and a mouthguard, with the goalie being the only player to wear a helmet. 

While helmets are mandatory for male players, it is merely optional for females. One argument against mandatory helmets is lacrosse traditionalists fear female athletes will begin playing the game more aggressively and dangerously.

According to Dr. Amanda Esquivel, associate professor of Mechanical Engineering at the University of Michigan-Dearborn, female players suffer numerous head injuries resulting from inadvertent collisions with other players, falls to the ground, or getting struck by various pieces of equipment. 

Esquivel-lab
Esquivel purchased a linear impactor and a crash test dummy to test how well the headgears would reduce various concussion metrics.

Companies have now begun developing soft headgear to help combat this issue. Esquivel explained that the headgear uses foams made from different densities on the outside and inside of the helmet. Because it does not have a hard outer shell, she wanted to know how well this headgear would reduce various concussion metrics. 

Now U-M Dearborn’s Impact Biomechanics Lab, led by Dr. Esquivel, is conducting a pilot study on how well the foams reduce head acceleration metrics at higher impact velocities.

Typically linear acceleration (the change of velocity without a change of direction) and rotational velocity and acceleration (how quickly an object rotates around a point) are the metrics used when studying head protection. “There is thought that these rotational measurements are as important, if not more important, in reducing concussions and mild traumatic brain injuries. So, we need to determine how protective headgear might affect rotational, as well as linear metrics.”

Esquivel’s preliminary data shows that at higher speeds, two commercially available headgears did lower both rotational and linear metrics that are related to head injury when compared with impacts to the headform alone.

“It’s always important to try and understand what’s going on with these head injuries so we can look towards some type of injury prevention,” Esquivel said. “Gathering information about head kinematics on the field or how many impacts we should expect can help you establish baseline information to work from.”

She is also looking into head injuries caused by falls in elderly populations in addition to her sport-related concussion research. Given there are hundreds of incidents of falls in nursing homes, one of her students is trying to reconstruct those injuries in the lab to begin gathering information about the types of injuries one would expect to see.

Future studies related to soft headgear include determining if cold weather affects the material properties and looking at how soft foam helmets affect neck strength and movement are planned. “When you add mass to the head, that will make it harder for the neck to control the head motion, which is true for big, heavy, full hard helmets. They are pretty light, so you may or may not have that issue,” Esquivel said.