It is a devastating neurological disease that takes the body hostage and then methodically destroys it while the mind stays painfully alert.

Lou Gehrig’s disease is still incurable and largely untreatable, but a stream of recent scientific breakthroughs in genetics, neuroscience, and regenerative medicine—plus the determination of committed researchers and physicians to slow or stop ALS’ brutal march—could be a game changer.

The instant Sal Silva’s bat struck the ball, he knew it was gone, and he started his home-run trot. “I just crushed the ball and thought, ‘I’m going to have a good season,’” he says, reflecting on a game in early 2010. At 61, his off-season workouts were paying off.

An electrician, Sal never missed work because of illness, but he gladly sacrificed some Fridays for his favorite pastime: swinging a bat and chasing down hits in the outfield for a local softball team that sometimes traveled to other states for long weekend tournaments.

But the homers stopped coming that season. His arms felt strong, and plenty of his hits found the gap in the outfield, but his right leg seemed too weak to power the ball over the fence. He started to stumble, too.

“When I was running, one foot would go and the other would not, and I would trip. That was when I really knew something was going on,” Sal says. He pauses and grips the arms of his wheelchair, shifting position to take pressure off his diaphragm.

For 40 years, his cheerful voice and easy laugh had mingled with the rattle of the toolbox he lugged around his workplace at The Walt Disney Company’s home office in Burbank. When his failing muscles began to endanger his life on the job, he consulted a neurologist. Then a second one.

Early hopes of a minor ailment quickly dimmed as increasing weakness and growing batteries of tests pointed toward amyotrophic lateral sclerosis (ALS)—also known as Lou Gehrig’s disease, named after the New York Yankees Hall of Famer who is believed to have succumbed to it in 1941. ALS attacks motor neurons in the brain and spinal cord—nerve cells that send electrical signals to muscle cells in the body. As the cells die, muscles weaken and waste away. But because most forms of the disease only affect muscle-controlling neurons, mental status and awareness usually remain as sharp as ever.

“ALS may be the cruelest, most severe neurological disease,” says Clive Svendsen, PhD, director of the Cedars-Sinai Regenerative Medicine Institute, who has studied the disease for a decade. “It typically starts with muscle twitching and weakness in one limb. Within six months to a year, that limb will be totally paralyzed and floppy. The disease moves on to the next limb, usually the opposite one. It eventually affects breathing, and the only way to survive is to be attached to a ventilator, totally paralyzed in a wheelchair.”

ALS affects 30,000 to 50,000 Americans, a relatively small number when compared to other neurological diseases such as multiple sclerosis or Parkinson’s. But that statistic is deceiving.

“The risk is about the same as some other well-known neurological diseases, but ALS is a nasty killer,” says Dr. Svendsen. “There is, sadly, no accumulation of patients. ALS often strikes people in their 40s and 50s, in their most productive years. This is a horrific disease that breaks your heart. We really have to do something about it.”

Tags: ALS, Clive Svendsen, Lou Gehrig's disease, Regenerative Medicine, Robert Baloh, sal