Nobody knows what Sigrid Leirmo was thinking.
A little after 8:30 a.m. on Oct. 23, 1990, Leirmo settled her car into Lot 60 on the UW campus and released her bike from its rack. Sigrid hadn't cycled much as a child and was not a hardcore biker. When she bought her first mountain bike as an adult, she'd even practiced in quiet areas before venturing into traffic. Her bike was simply a practical way to get from her car to her bacteriology lab.
She didn't make it. Pedaling onto Willow Drive -- which at the time accommodated both cars and a 10-foot-wide bike path -- she rounded a corner and headed up the slight grade, where she encountered Gerald Hall riding in the other direction. "Both zigged, both zagged, both zigged again," UW-Madison Police Lt. Gary Moore told the Wisconsin State Journal. About 50 feet from the entrance to Willow Beach they collided with force enough to bend Leirmo's frame. She went flying, hit her bare head, went dark.
Sigrid Leirmo never regained consciousness and was declared dead at UW Hospital at 9:50 that morning. The coroner determined that, had she been wearing a helmet, she would probably have lived. Gerald Hall, wearing his helmet, cut himself up and lost a tooth, but walked away.
Leirmo's father and cousin collected her car afterwards. On the passenger seat was Sigrid's helmet. "That was a real shock to me," recalls her cousin Robert Rand. Her father, David Leirmo, remembers two helmets in the car. Family, friends and colleagues all remarked that she was a cautious type, a helmet wearer. Why hadn't she put it on?
I have never been able to shake the wild random circumstances of this crash. Such a small decision, such a minute deviation from her norm, and suddenly, Sigrid Leirmo is gone.
I've been thinking a lot more about it lately because I've noticed more and more bare-headed bikers. I'm often out during commute time, and suddenly it seemed like helmets were in decline. There was a new generation of younger, hipper urban bikers who seemed to bare their heads with rebel pride. I see families out, the kids helmeted and the parents unprotected.
To be clear, I'm a helmet wearer, and I'm comfortable cautioning kids I know. I am not interested in mandating helmets, at least for adults. I understand the allure. A helmet can feel awkward and artless, and the wind in your hair is a liberating, sensual feeling. So I'm told.
But I'm also perplexed. In the last decade our long-running wars have given us a painfully public knowledge of traumatic brain injury. We know more about concussion problems that could transform the sporting scene. New imaging science has wrapped probing fingers around our gray matter, giving us a wondrous view into our brain's strength, plasticity and ultimate fragility.
I love that more people are biking. But why do we choose now to stop wearing helmets? What would Sigrid think?
The case for and against
We are in a golden age of cycling. Gorgeous machines regularly spin by, sleek frames in eye-popping, candy-coated splendor. With matching wheel sets! Some employ technology that, on a larger scale, might take you to the moon. Others are simple triangles and circles of steel with 30-year-old components.
And after decades of struggle, bicycles are finally winning belated recognition as important players in our transportation economy. Having secured some share of our massive public roads expenditure, infrastructure for cyclists is on the rise. Intrepid riders and entrepreneurs keep stretching the boundaries, pushing bikes into places you never saw them just a decade ago.
Helmets remain an area of active debate. Statistically speaking, there's no data to support my observation that helmet use is in decline. Recent studies have found about 60% of commuters wear helmets. Women were more likely to wear helmets, and virtually all of the riders without helmets are under 30.
A lot of studies have been done trying to tease out what makes bikers safe. Sometimes helmet use is shown to have a positive influence. Other research shows that helmet laws and even militant helmet advocacy tend to discourage cycling. Investments in biking infrastructure have a clear benefit. "An argument can be made that mandatory helmet laws and/or militant advocacy of helmet use actually make the cyclists that are still on the road less safe because they are not surrounded by as many other cyclists”, experts say.
Other research suggests that in aggregate the health benefits from being active are overwhelmingly more positive than the health detriments from cycling injuries. It's an intriguing case for building a bike culture. But don't confuse population benefits with the personal ones.
Dr. Lee Faucher, a trauma surgeon, knows helmets are a hard sell. He and some colleagues once analyzed the hospital's accident data. Experience and intuition told them that helmets matter, but accidents are complex events that don't easily fit statistical models. They couldn't prove that helmets save lives.
But Faucher can tell you what happens when your head hits something hard. "All the energy is transferred to the inside," he explains. "The skull hits the object, and then the brain hits the inside of the skull," he says. What helmets do is reduce the energy transferred to the brain. Like an airbag or a crumple zone, they slow down the crash.
The brain is a very complex electrical circuit, and a head injury scrambles communication between brain cells. "It just is not going to work very well," Faucher says. Impact also disrupts the delicate network of arteries and veins, and bleeding can disrupt brain function. If the bleeding is bad enough, pressure builds within the skull, which decreases blood flow. Any oxygen deprivation leads to further dysfunction down the road.
Neurosurgeon Josh Medow picks up the story from there. While a helmet is no guarantee, in his experience, most people wearing helmets are fine and ready to go in a couple of days.
Recovering from head trauma, on the other hand, can be a significant challenge. Imagine not being able to balance a checkbook or not being able to read a newspaper article once and understand it. You might have weakness in a limb or a side of the body, or difficulty speaking. You might lose motivation, even moxie. Many trauma victims will gain a substantial amount of weight. Parts of you may never be the same.
ARIZONA BIKE HELMET LAW:
There is no helmet requirement (except for those under 18). But, if you are in an accident, and the defense/insurance company can later prove that you would not have sustained the same injuries had you been wearing a helmet, you may be denied a recovery for your injuries. Really? Yep. That’s the law.
Be smart. Wear your helmet. It may just save your life.