by Mary Roach
Steering wheel columns up through the sixties were narrow, sometimes only six or seven inches in diameter. Just as a ski pole will sink into the snow without its circular basket, a steering column with its rim flattened back will sink into a body. In an unfortunate design decision, the steering wheel shaft of the average automobile was angled and positioned to point straight at the driver’s heart.* In a head-on, you’d be impaled in pretty much the last place you’d want to be impaled. Even when the metal didn’t penetrate the chest, the impact alone was often fatal. Despite its thickness, an aorta ruptures relatively easily. This is because every other second, it has a one-pound weight suspended from it: the human heart, filled with blood. Get the weight moving with enough force, as happened in blunt impacts from steering wheels, and even the body’s largest blood vessel can’t take the strain. If you insist on driving around in vintage cars with no seat belt on, try to time your crashes for the systole—blood-squeezed-out—portion of your heartbeat.
With all this in mind, bioengineers and automobile manufacturers (GM, notably) began ushering cadavers into the driver’s seats of crash simulators, front halves of cars on machine-accelerated sleds that are stopped abruptly to mimic the forces of a head-on collision. The goal, one of them anyway, was to design a steering column that would collapse on impact, absorbing enough of the shock to prevent serious injury to the heart and its supporting vessels. (Hoods are now designed to do this too, so that even cars in relatively minor accidents have completely jackknifed hoods, the idea being that the more the car crumples, the less you do.) GM’s first collapsible steering wheel shaft, introduced in the early 1960s, cut the risk of death in a head-on collision by half.
And so it went. The collective cadaver résumé boasts contributions to government legislation for lap-shoulder belts, air bags, dashboard padding, and recessed dashboard knobs (autopsy files from the 1950s and 1960s contain more than a few X-ray images of human heads with radio knobs embedded in them). It was not pretty work. In countless seat-belt studies—car manufacturers, seeking to save money, spent years trying to prove that seat belts caused more injuries than they prevented and thus shouldn’t be required—bodies were strapped in and crashed, and their innards were then probed for ruptures and manglings. To establish the tolerance limits of the human face, cadavers have been seated with their cheekbones in the firing lines of “rotary strikers.” They’ve had their lower legs broken by simulated bumpers and their upper legs shattered by smashed-in dashboards.
It is not pretty, but it is most certainly justifiable. Because of changes that have come about as a result of cadaver studies, it’s now possible to survive a head-on crash into a wall at 60 mph. In a 1995 Journal of Trauma article entitled “Humanitarian Benefits of Cadaver Research on Injury Prevention,” Albert King calculated that vehicle safety improvements that have come about as a result of cadaver research have saved an estimated 8,500 lives each year since 1987. For every cadaver that rode the crash sleds to test three-point seat belts, 61 lives per year have been saved. For every cadaver that took an air bag in the face, 147 people per year survive otherwise fatal head-ons. For every corpse whose head has hammered a windshield, 68 lives per year are saved.
Unfortunately, King did not have these figures handy in 1978, when chairman John Moss of the House Subcommittee on Oversight and Investigations called a hearing to investigate the use of human cadavers in car crash testing. Representative Moss said he felt a “personal repugnance about this practice.” He said that there had developed within NHTSA “a sort of cult that finds that this is a necessary tool.” He believed that there had to be another way to go about it. He wanted proof that dead people in crashing cars behave exactly like living ones—proof that, as exasperated researchers pointed out, could never be obtained because it would mean subjecting a series of live humans to exactly the same high-force impacts as a series of dead humans.
Oddly, Representative Moss was not a squeamish man when it came to dead bodies; he had worked briefly in a funeral parlor before he entered politics. Nor was he an especially conservative man. He was a Democrat, a pro-safety reformer. What had got him agitated, said King (who testified at the hearing), was this: He had been working to pass legislation to make air bags mandatory and was infuriated by a cadaver test that showed an air bag causing more injury than a seat belt. (Air bags sometimes do injure, even kill, particularly if the passenger is leaning forward or otherwise OOP—“out of position”—but in this case, to be fair to Moss, the air bag body was older and probably frailer.) Moss was an oddity: an automotive safety lobbier taking a stand against cadaver research.
In the end, with the support of the National Academy of Sciences, the Georgetown Center for Bioethics, the National Catholic Conference, a chairman of a noted medical school’s anatomy department who stated that “such experiments are probably as highly respectful [as medical school anatomy dissections] and less destructive to the human body,” and representatives of the Quaker, Hindu, and Reform Judaism religions, the committee concluded that Moss himself was a tad “out of position.” There is no better stand-in for a live human in a car crash than a dead one.
Lord knows, the alternatives have been tried. In the dawn of impact science, researchers would experiment on themselves. Albert King’s predecessor at the Bioengineering Center, Lawrence Patrick, volunteered himself as a human crash test dummy for years. He has ridden the crash sled some four hundred times, and been slammed in the chest by a twenty-two-pound metal pendulum. He has hurled one knee repeatedly against a metal bar outfitted with a load cell. Some of Patrick’s students were equally courageous, if courageous is the word. A 1965 Patrick paper on knee impacts reports that student volunteers seated in crash sleds endured knee impacts equivalent to a force of one thousand pounds. The injury threshold was estimated at fourteen hundred pounds. His 1963 study “Facial Injuries—Cause and Prevention” includes a photograph of a young man who appears to be resting peacefully with his eyes shut. Closer inspection hints that, in fact, something not at all peaceful is about to unfold. For starters, the man is using a book entitled Head Injuries as a headrest (uncomfortable, but probably pleasanter than reading it). Hovering just above the man’s cheek is a forbidding metal rod identified in the caption as a “gravity impactor.” The text informs us that “the volunteer waited several days for the swelling to subside and then the test was continued up to the energy limit which he could endure.” Here was the problem. Impact data that doesn’t exceed the injury threshold is of minimal use. You need those folks who don’t feel pain. You need cadavers.
Moss wanted to know why animals couldn’t be used in automotive impact testing, and indeed they have been. A description of the Eighth Stapp Car Crash and Field Demonstration Conference, which appears in the introduction to its proceedings, begins like a child’s recollections of a trip to the circus: “We saw chimpanzees riding rocket sleds, a bear on an impact swing…. We observed a pig, anaesthetized and placed in a sitting position on the swing in the harness, crashed into a deep-dished steering wheel….”
Pigs were popular subjects because of their similarities to humans “in terms of their organ setup,” as one industry insider put it, and because they can be coaxed into a useful approximation of a human sitting in a car. As far as I can tell, they are also similar to a human sitting in a car in terms of their intelligence setup, their manners setup, and pretty much everything else, excluding possibly their use of cupholders and ability to work the radio buttons, but that is neither here nor there. In more recent years, animals have typically been used only when functioning organs are needed, and cadavers cannot oblige. Baboons, for example, have been subjected to violent sideways head rotations in order to study why side-impact crashes so often send passengers into comas. (Researchers, in turn, were subject to violent animal rights protests.) Live dogs were recruited to study aortic rupture; for unknown reasons, it has proved difficult to experimentally rupture a cadaver aorta.
There is one type of automotive impa
ct study in which animals are still used even though cadavers would be vastly more accurate, and that is the pediatric impact study. No child donates his remains to science, and no researcher wants to bring up body donation with grieving parents, even though the need for data on children and air-bag injuries has been obvious and dire. “It’s a real problem,” Albert King told me. “We try to scale it from baboons, but the strength is all different. And a kid’s skull is not completely formed; it changes as it grows.” In 1993, a research team at the Heidelberg University School of Medicine had the courage to attempt a series of impact studies on children—and the audacity to do it without consent. The press got hold of it, the clergy got involved, and the facility was shut down.
Child data aside, the blunt impact tolerance limits of the human body’s vital pieces have long ago been worked out, and today’s dead are being recruited mainly for impact studies of the body’s outlying regions: ankles, knees, feet, shoulders. “In the old days,” King told me. “people involved in severe crashes ended up in the morgue.” No one cares about a dead man’s shattered ankle. “Now these guys are surviving because of the air bag, and we have to worry about these things. You have people with both ankles and knees damaged and they will never walk right again. It’s a major disability now.”
Tonight at Wayne State’s impact lab, a cadaver shoulder impact is taking place, and King has been gracious enough to invite me to watch. Actually, he didn’t invite me. I asked if I could watch, and he agreed to it. Still, considering what I’ll be seeing and how sensitive the public is to these things and further considering that Albert King has read my writing and knows it doesn’t exactly read like The International Journal of Crashworthiness, he was pretty darn gracious.
Wayne State has been involved in impact research since 1939, longer than any other university. On the wall above the landing of the front stairs of the Bioengineering Center a banner proclaims: “Celebrating 50 Years of Moving Forward with Impact.” It is 2001, which suggests that for twelve years now, no one has thought to take down the banner, which you kind of expect from engineers.
King is on his way to the airport, so he leaves me with fellow bioengineering professor John Cavanaugh, who will be overseeing tonight’s impact. Cavanaugh looks at once like an engineer and a young Jon Voight, if that’s possible. He has a laboratory complexion, pale and unlined, and regular-looking brown hair. When he talks or shifts his glance, his eyebrows rise and his forehead draws together, giving him a more or less permanent look of mild worry. Cavanaugh brings me downstairs to the impact lab. It is a typical university lab, with ancient, jerry-rigged equipment and decor that runs to block-lettered safety reminders. Cavanaugh introduces me to Matt Mason, tonight’s research assistant, and Deb Marth, for whose Ph.D. dissertation the impact is being done, and then he disappears upstairs.
I glance around the room for UM 006, the way, as a child, I used to scan the basement for the thing that reaches through the banisters to grab your legs. He isn’t here yet. A crash test dummy sits on a sled railing. Its upper body rests on its thighs, head on knees, as though collapsed in despair. It has no arms, perhaps the source of the despair.
Matt is linking up high-speed videocameras to a pair of computers and to the linear impactor. The impactor is a formidably sized piston fired by compressed air and mounted on a steel base the size of a fairground pony. From the hallway, a sound of clattering wheels. “Here he comes,” says Deb. UM 006 lies on a gurney being wheeled by a muscular man with gray hair and rambunctious eyebrows, dressed, like Marth, in surgical scrubs.
“I am Ruhan,” says the man beneath the eyebrows. “I am the cadaver man.” He holds out a gloved hand. I wave, to show him that I’m not wearing gloves. Ruhan comes from Turkey, where he was a doctor. For a former doctor whose job now entails diapering and dressing cadavers, he has an admirably upbeat disposition. I ask him if it’s difficult to dress a dead man, and how he does it. Ruhan describes the process, then stops. “Have you ever been to a nursing home? It’s like that.”
UM 006 is dressed this evening in a Smurf-blue leotard and matching tights. Beneath the tights he wears a diaper, for leakage. The neckline of his leotard is wide and scooped, like a dancer’s. Ruhan confirms that the cadaver leotards are purchased from a dancers’ supply house. “They would be disgusted if they knew!” To ensure anonymity, the dead man’s face is masked by a snug-fitting white cotton hood. He looks like someone about to rob a bank, someone who meant to pull pantyhose over his head but got it wrong and used an athletic sock.
Matt sets down his laptop and helps Ruhan lift the cadaver into the car seat, which sits on a table beside the impactor. Ruhan is right. It’s nursing-home work: dressing, lifting, arranging. The distance between the very old, sick, frail person and the dead one is short, with a poorly marked border. The more time you spend with the invalid elderly (I have seen both my parents in this state), the more you come to see extreme old age as a gradual easing into death. The old and the dying sleep more and more, until one day they “sleep” all the time. They often become more and more immobile until one day they can do no more than lie or sit however the last person positioned them. They have as much in common with UM 006 as they do with you and me.
I find the dead easier to be around than the dying. They are not in pain, not afraid of death. There are no awkward silences and conversations that dance around the obvious. They aren’t scary. The half hour I spent with my mother as a dead person was easier by far than the many hours I spent with her as a live person dying and in pain. Not that I wished her dead. I’m just saying it’s easier. Cadavers, once you get used to them—and you do that quite fast—are surprisingly easy to be around.
Which is good, because at the moment, it’s just he and I. Matt is in the next room, Deb has gone to look for something. UM 006 was a big, meaty man, still is. His tights are lightly stained. His leotard shows up his lumpy, fallen midsection. The aging superhero who can’t be bothered to wash his costume. His hands are mittened with the same cotton as his head. It was probably done to depersonalize him, as is done with the hands of anatomy lab cadavers, but for me it has the opposite effect. It makes him seem vulnerable and toddlerlike.
Ten minutes pass. Sharing a room with a cadaver is only mildly different from being in a room alone. They are the same sort of company as people across from you on subways or in airport lounges, there but not there. Your eyes keep going back to them, for lack of anything more interesting to look at, and then you feel bad for staring.
Deb is back. She is checking accelerometers that she has painstakingly mounted to exposed areas of the cadaver’s bones: on the scapula, clavicle, vertebrae, sternum, and head. By measuring how fast the body accelerates on impact, the devices essentially give you the force of the hit, as measured in g’s (gravities). After the test, Deb will autopsy the shoulder area and catalog the damage at this particular speed. What she is after is the injury threshold and the forces needed to generate it; the information will be used to develop shoulder instrumentation for the SID, the side-impact dummy.
A side-impact accident is one in which the cars collide at ninety degrees, bumper to door, the kind that often take place at four-way intersections when one party hasn’t bothered to stop at the light or heed the stop sign. Lap-shoulder belts and dashboard air bags are engineered to protect against the forward-heaving forces of a head-on crash; they do little for a person in a side-impact crash. The other thing working against you in this type of crash is the immediacy of the other car; there is no engine or trunk and rear seat to absorb the blow.* There are a couple inches of metal door. This is also the reason it took so long for side air bags to begin appearing in cars. With no hood to collapse, the sensors have to sense the impact immediately, and the old ones weren’t up to the task.
Deb knows all about this because she works as a design engineer at Ford and was the person who implemented the side air bags in the 1998 Town Car. She doesn’t look like an engineer. She has magazine-model skin and a wide, wh
ite, radiant smile and thick, shiny brown hair pulled back in a loose ponytail. If Julia Roberts and Sandra Bullock had a child together, it would look like Deb Marth.
The cadaver before UM 006 was hit at a faster speed: 15 mph (which, were this a real side-impact accident with a passenger door to absorb some of the energy of the impact, would translate to being hit by a car going perhaps 25 or 30 mph). The impact broke his collarbone and scapula and fractured five ribs. Ribs are more important than you think. When you breathe, you not only need to move your diaphragm to pull air into your lungs, you need the muscles attached to your ribs and the ribs themselves. If all your ribs break, your rib cage can’t help inflate your lungs the way it’s supposed to, and you will find it very hard to breathe. It is a condition called “flail chest,” and people die from it.
Flail chest is one of the other things that make side impacts especially dangerous. Ribs are easier to break from the side. The rib cage is built to be compressed from the front, sternum to spine—that’s how it moves when you breathe. (Up to a point, that is. Compress it too far and you can, in the words of Don Huelke. “split the heart completely in half as you would a pear.”) A rib cage is not built for the sideways press. Slam it violently from the side, and its tines tend to snap.
