When 67-year-old Dean Malliaros was facing spine surgery in September, he took a chance few others have.
He volunteered for a procedure his doctor had never performed, using a joint replacement that still needs five more years of study before it is approved by the U.S. Food and Drug Administration.
At stake was Malliaros' ability to continue his normal daily activities, and possibly even his ability to walk. He suffers from spinal stenosis, a condition where the bones or ligaments in the spinal canal begin to thicken and narrow, slowly squeezing and clamping down on the spinal cord over time.
Current treatments for the condition are not perfect, and the new procedure is not without its risks. Any time doctors implant an artificial joint, there is a concern that natural wear and tear will grind off microscopic particles of the metal joint — a "dust" of sorts. If this dust is somehow harmful to surrounding tissues, doctors — and the patient — can have a big problem on their hands.
And then there is the worry of how long the joint will last, especially since the quicker it wears out, the sooner the patients will have to return for major — as possibly risky — surgery.
But the success of this implant could have big implications for others who suffer from spinal stenosis. As many as 500,000 people in the United States — most of them older than 50 — suffer from noticeable symptoms, according to the University of Washington Orthopedics and Sports Medicine Department.
People with spinal stenosis can lose control over their bladders and experience erectile dysfunction. Sufferers may also find that their feet go numb, their legs hurt, and they begin to hunch over — a motion that allows slightly more wiggle room for their nerves in their spine.
"You can go to the grocery store on a Tuesday afternoon, and see people with spinal stenosis leaning on their grocery cart trying to make it around," said Daryll Dikes, an orthopedic spine surgeon in Minneapolis, Minn.
Despite the pain associated with this condition, medical advancements to treat joint pain in the spine have lagged behind joints in other parts of the body. Replacement ball-and-socket joints like the hip and simple-hinge joints like the knee have been around for decades. But the facet joints in the spine are more difficult for medical engineers to replicate.
For nine years, Malliaros tried the usual treatments for spinal stenosis: epidural injections and heavy-duty nerve blocks for the pain. But the condition got worse, and Malliaros, who used to regularly swim and run, could only walk with a cane and for short distances. At that point his doctor called him in for a surgery consultation.
Sitting in the waiting room, Malliaros began to feel less optimistic about his options.
"They all were complaining that they wished they had never had a [spinal] fusion operation done because of the rigidity," said Malliaros. "You always have problems above and below the fusion."
Spinal fusion surgery is currently the last resort for people with spinal stenosis. Sometimes doctors can remove the tiny bone spurs that leave nerves red and inflamed, but often so much of the facet joint has degenerated that fusing two vertebrae into one gives the best pain relief.
Spinal fusion makes space for the nerves, but it puts the vertebrae on either side of the fusion in under extra stress.