The dancer with the torn disk had IDET this summer, Dr. Lutz said, and is ”definitely better.” She hopes to be able to resume her career. For patients like her, with torn disks but no other major disk degeneration, Dr. Lutz’s success rate is 75 percent to 80 percent, he said.
Whether IDET becomes a standard treatment will depend on studies like a multicenter trial that is being run by Dr. F. Todd Wetzel, an orthopedic surgeon who is medical director at the University of Chicago Spine Center. The study involves 74 patients; 38 of them had the therapy at least two years ago, and more than 70 percent of the patients say the procedure helped them, Dr. Wetzel said in an interview.
”Since I’m not one of the developers of the technique and brought a skeptical bias to the study,” Dr. Wetzel said, ”I think our data have been well received. They show fairly high patient satisfaction.”
Dr. Wetzel and his colleagues will present positive data about IDET at the North American Spine Society’s annual meeting, which begins tomorrow in New Orleans, as will other researchers.
For patients with intractable lower-back pain linked to deteriorating disks, IDET could well fill a therapeutic gap, Dr. Wetzel said. ”Now, we’ve essentially got a fly swatter and an elephant gun, and not much in between,” Dr. Wetzel said.
Questions about the new therapy may be settled in many doctors’ minds by the first double-blind IDET clinical trial, which will include 75 patients. The study’s director, Dr. Robert D. Fraser, a professor of orthopedic surgery at the University of Adelaide in Australia, said the study would have all its participants next January and would be completed in July 2001.
”Quite frankly,” Dr. Wetzel said, ”Dr. Fraser’s study will be absolutely critical.”
Another double-blind study is just beginning in Tyler, Tex. That study is by Dr. Kevin Pauza at the East Texas Medical Center Neurological Institute.
If it turns out to be effective over the long term, intradiskal therapy will be a lower-cost alternative to fusion surgery for some kinds of disk problems. An IDET treatment runs about $5,000 to $8,000, while fusion may cost more than $40,000.
The question is whether it is effective and safe. Until the procedure is proved, many insurance companies will consider it experimental and refuse to pay for treatments.
One major question about IDET’s long-term safety focuses on what happens to the internal structure of the disk over time. Just as applying heat to an egg white tangles its proteins and makes it more solid, applying heat to a disk’s outer covering changes the structure of its collagen protein. So it is still a question as to whether a disk that has been sealed by heat will act as an effective shock absorber for the spine.
Dr. Lutz and others have done safety studies that have been reassuring. But only long-term research can resolve the questions of what happens to the heat-treated collagen and whether nerve endings will grow back and cause more problems.
How well IDET patients do over time will determine if the initial enthusiasm by many doctors is justified. Many patients say they are glad that they had the procedure.
One of them is Diane Pearce, an administrative assistant to the associate provost at Princeton. By the time Ms. Pearce, 58, saw Dr. Lutz, she had tried one treatment after another.
”I had no life,” she said. ”I’d go home from work and lie down. I couldn’t go to the movies or a restaurant. The longer I sat, it would keep getting worse.”
In March 1999, Dr. Lutz performed one procedure on one of Ms. Pearce’s disks, and then he did another on a second disk in September 1999.
Last April, she felt well enough for her first outing with friends in three years.
”We took a bus to New York and went to Duffy Square,” she said. ”I saw ‘Kiss Me Kate’ and took the bus home. I wanted to kiss Dr. Lutz.”
That doesn’t mean she’s ready to go back to tennis and aerobics. She still finds it hard to sit for long periods and cannot do much lifting. But she can walk two miles, and she hopes that next year she’ll be able to take a plane trip.
”I have stiffness,” she said. ”But the pain is gone.”