Catherine Wolf's feet used to point and flex in modern dance class. Now they rest motionless on the footrest of her wheelchair in jeweled ballerina flats.
A matching beaded necklace swoops under a tube that pumps air into her lungs through a hole in her neck. Every 15 minutes, a raspy gargle prompts a nearby nurse to disconnect the tube and suction the build-up of mucous in her lungs. This takes about 10 seconds, during which the smooth, pale skin of Wolf's face turns red like her curly hair and an alarm buzzes loudly.
There's no need for concern, this is routine. It has been 14 years since Wolf, 63, was diagnosed with Lou Gehrig's disease, which has trapped her inside a paralyzed body, silenced her and nearly suffocated her by killing the nerves that control her muscles.
Since Lou Gehrig's famous retirement from baseball in 1939, amyotrophic lateral sclerosis -- the deadly neurological disease that ended the Yankee slugger's 37-year life -- has borne his name. So when an August 2010 research study and the media coverage it garnered challenged the appropriateness of the moniker, it provoked frustration among researchers and confusion and skepticism among patients like Wolf.
"Here he is, the face of his disease, and he may have had a different disease as a result of his athletic experience," study lead author Dr. Ann McKee of Boston University School of Medicine and the New England Veterans Affairs HealthCare System, told a New York Times reporter.
But Dr. Stanley H. Appel, chairman of neurology and director of the Methodist Neurological Institute in Houston, is arguing the claim, calling it a disservice to Gehrig and others with living with ALS.
Appel says there is a lack of scientific evidence to support claims that ''brain trauma can mimic Lou Gehrig's disease'' and that ''maybe Lou Gehrig didn't die of Lou Gehrig's disease," which were printed by The New York Times and Time Magazine respectively. ABC News also covered the study.
"Whether head trauma may have played a role in Gehrig's development of ALS can never be verified, but it is a complete disservice to his place in history as an icon for ALS to suggest that his disease was not ALS," Appel and colleagues wrote in an editorial published in the journal Muscle & Nerve.
What McKee's study actually showed is that chronic traumatic encephalopathy (CTE) -- a condition that stems from repetitive head injuries such as those tolerated by boxers, football players and hockey players -- bears semblance to ALS at the microscopic level. In particular, a protein known to be abnormal in degenerating motor neurons in ALS called TDP-43 also was found to be abnormal in the brains of individuals with CTE -- three of whom went on to be diagnosed with ALS later in life.
Headlines about a trauma-induced ALS doppelganger sparked hopes among some patients that they may have been misdiagnosed, as well as worries among others that their fates somehow might have been preventable.
Wolf remembered what might have been her earliest symptoms back in the summer of 1996: The pain that pierced through her left calf after a routine run and her left foot's refusal to flex during dance class. She switched to swimming to give her leg a chance to heal. The following winter, perplexed doctors treated her for nerve damage, but her symptoms only worsened.
"I knew ALS was a possibility, but I pushed it to the back of my mind in favor of treatable conditions," she recalled.
But the diagnosis evolved until there were no other prospects. By the fall of 1998, Wolf accepted the devastating consensus from three independent ALS specialists.
Despite major advances in ALS research over the past decade -- including the discovery of new genetic mutations and faulty proteins now known contribute to the demise of afflicted motor neurons -- the cause of ALS, and a cure, remain elusive. Although one in 10 patients has an inherited form of the disease, the majority of cases are sporadic and thought to stem from a cruel, complex interaction of genetic and environmental risk factors.
"It is hard to accept that ALS randomly struck you," said Wolf.
Most people with ALS first experience weakness in a limb. But as the disease progresses, more limbs are affected and the ability to speak, swallow and breathe is lost, it seems less plausible that a focal injury was involved, she said.
"That said, the human mind wants reasons," Wolf said. "I sometimes wonder if my moderate running -- 15 miles per week for about 10 years prior to ALS -- interacted with some genetic susceptibility."
Although the disease started in her legs, Wolf already was slurring words six months after her diagnosis. Planning for the unthinkable, she recorded phrases in her own voice, like 'thank you' and 'goodbye,' the names of family, and a few third-grade jokes like, 'What's green and hangs from trees? Giraffe snot.' She wishes she had recorded more.
Researchers long have suspected there was a link between ALS and injuries sustained during sport or combat.
In a 2007 study published in the American Journal of Epidemiology, individuals who reported having sustained repeated head injuries were three times more likely to have ALS than those who said they were injury-free.
In other studies, the incidence of ALS among professional soccer players in Italy and professional football players in North America was higher than normal. War veterans also are thought to have a heightened risk.
"It's very possible that physical injury may be some kind of trigger, but it's absolutely not the cause," said Lucie Bruijn, ALS researcher and senior vice president of research and development for the ALS Association.
While nerve injury might exacerbate the disease, Bruijn stressed that there's clearly an underlying genetic predisposition.
"The impact of the article was a real confusion among patients," Bruijn said. "I think there was concern over what this might mean for their diagnosis and their disease."
Wolf understands how patients like her could experience this kind of confusion.
"The [New York] Times is a reputable source, and despite the ALS Association's cautionary statement, many people might have believed their disease was a result of preventable behavior," she said.
McKee was sorry to hear that clinicians felt her study had upset their patients, she said. But her reaction from patients has been very different.
"Many of them do feel that trauma was an initial event, and many of them have a significant history of head and neck trauma," she said. "They're relieved that someone is giving it a serious look."
"What both sides appear to attest -- that ALS is a clinical diagnosis which Lou Gehrig had, and that some patients diagnosed with ALS have a form of it caused by brain trauma that can have an additional name but remain under the ALS motor-neuron-disease umbrella -- can in fact coexist rather comfortably until everything is sorted out," said Alan Schwarz, the New York Times reporter who covered McKee's study. "If arms were dropped and messages were delivered more clearly and logically, they would find that they disagree much less than it looks."
While the cause of Lou Gehrig's disease is as unclear today at it was in 1939, one thing is certain: What he had was Lou Gehrig's disease, and no one else's.
"Amyotrophic lateral sclerosis is a mouthful," said Wolf. "Most people don't know what ALS is. If you call it Lou Gehrig's disease, it has a face, the face of one of the greatest baseball players ever."