Any injury to the head, mild to severe, can disable someone; injuries to the neck can cause paralysis, she said. "The whole spectrum of injury involves the whole spectrum of possibilities."
Every day in Utah, 37 people are treated for TBIs and released from emergency rooms, according to the Utah Department of Health. Another seven are hospitalized or die.
Falls, especially among the elderly, are the leading cause, followed by car accidents, suicide and suicide attempts. Fewer than 5 percent of 2,247 TBIs in 2009, the most recent data available, were caused by assault.
But assaults are more commonly faulted than team sports injuries, such as "having your bell rung" on the football field, which has gotten a lot of attention in recent years.
Nationally assaults account for 10 percent of traumatic brain injuries. In 2011, the FBI reported 728 homicides by hand, fist and feet.
"We don't have a lot of violence like some cities do," said Richard Schmidt, a neurosurgeon at the U. "But I've certainly seen people badly injured in fist fights."
And, unlike accidents, bar-room brawls and playground scuffles are 100 percent preventable.
Ricardo Portillo, a volunteer soccer referee, was removed from life support on Saturday after spending nearly a week in a coma triggered by injuries sustained when a 17-year-old player assaulted him during a game.
Witnesses told police the teenage goalie, enraged by a call, punched Portillo in the side of the head while Portillo was noting the penalty in a notebook.
Officers found him lying on the ground in the fetal position complaining of pain in his face and back. He was conscious, but nauseated and had spit up a small amount of blood.
Later, in the hospital, his brain swelled and his condition deteriorated.
Whether Portillo was hit once, or several times, isn't clear from witness accounts. But it might not matter.
In the summer of 2011, a Utah man died in a Las Vegas casino after being punched once in the head by another tourist. The attacker was convicted of involuntary manslaughter.
One punch thrown by a drunk outside a bowling alley in San Diego was enough to knock a 31-year-old former Marine unconscious in February 2003. He fell to the ground and his head hit the pavement. Two days later he died.
In February 2012, a 10-year-old girl in California died from injuries sustained in a fist-fight with an 11-year-old girl.
Prolonged fight scenes in movies where the hero walks away bruised, but unbroken, aren't realistic, said Paul Barker, retired police officer and defense expert who teaches tae kwon do at Champion Karate West in Provo. "People are naive to the risk." When Barker's students compete, they wear protective head gear with a face cage, gloves and guards for the chest, mouth and groin.
Hits to the face and certain hits to the head are off limits, such as reverse jab using the hand opposite your forward foot, he said. "That's very powerful and could kill someone instantly."
Barker teaches his students to avoid conflict and warns against punching someone in the temple, the thinnest, most fracture-prone part of the skull.
But doctors say a blow to any part of the head can injure underlying blood vessels.
"It could be a bruise or torn blood vessel or combination of both," said Schmidt, describing how pressure builds as blood builds up inside the skull, in severe cases strangling and starving the organ of adequate blood flow.
"You get a vicious cycle. The higher the pressure, the more normal blood flow is compromised, which in turn causes more brain damage, which in turn causes more brain swelling," he said.
People bang their head all the time, and it's designed to withstand a little of that.
"It obviously takes some force to cause damage…but it's a little unpredictable. If somebody is on blood thinners, it may take less to get significant bleeding to start," Schmidt said. "Sometimes it just comes down to bad luck. The right injury in exactly the right place may be worse for one person than for somebody else."
Brain injury in Utah
Years ago falls, especially among the elderly, surpassed car crashes as the leading cause of traumatic brain injury. Experts credit safety improvements and better engineering of roads. Following is a breakdown by cause of 2,247 traumatic brain injuries in Utah:
Falls • 33 percent
Motor vehicle traffic crashes • 18.3 percent
Suicide and suicide attempts • 11.5 percent
Off-highway, all-terrain vehicle accident • 5.5 percent
Assault • 4.7 percent
Motorcycle crashes • 4.5 percent
Bicycle crashes • 4.3 percent
Pedestrian accidents • 3.4 percent
Horse riding, rodeo accidents • 2.3 percent
Snow sports • 2.2 percent
Skateboard and rollerblade injuries • 1.8 percent
Team sports • 1.4 percent
Recreational injuries • 1.4 percent
Other • 4.8 percent
Source: Utah Department of Health When to seek medical help
Symptoms from a head injury can surface immediately or last days, weeks or longer. Recovery may be slower among older adults, young children and teens. Those who have had a concussion in the past are also at risk of having another one. Seek medical attention if you have:
A headache that gets worse and does not go away.
Weakness, numbness or decreased coordination.
Repeated vomiting or nausea.
Slurred speech or drowsiness.
One pupil larger than the other.
Convulsions or seizures.
Unusual behavior; you are confused, restless, or agitated.
Source: U.S. Centers for Disease Control