Orthopedics, a big moneymaker for many hospitals, will only grow in importance as aging baby boomers look for help with their painful joints.
Back trouble, in particular, will drive millions of patients to their doctors.
Hospitals take heart.
Although most back trouble subsides in time, persistent pain is more likely to be tackled in the operating room.
Crumbling discs are the usual target. More than 650,000 people had back surgery last year, and volume is growing at double-digit rates, says Thomas Gunderson, a medical technology analyst at U.S. Bancorp Piper Jaffray, Minneapolis. In fact, spine surgery is one of the fastest-growing procedures that's well-reimbursed, Gunderson says.
The most common spinal surgery-performed about 450,000 times in 1999-is the removal of bulging or damaged discs between the vertebrae. About two-thirds of the time, surgeons fuse the vertebrae after extracting the discs. This stabilizes the spine, reducing the odds of another operation being needed.
Although it might seem counterintuitive for a degenerative disease, the middle-aged are more likely to have these operations than the elderly.
The median age for spine surgery is 42. Many of these otherwise fit patients suffer from work-related back conditions, the leading cause of disability in adults. Workers' compensation pays for a higher proportion of spine surgeries than for any other condition.
"If you're an administrator, I think that's good," Gunderson says.
Employers, he explains, are more concerned with how fast the injured worker will return to work than with treatment costs. This focus on results translates into a typical payment to hospitals of $25,000 to $30,000 for spinal fusion. That, Gunderson says, is "nicely profitable."
Spine surgeons recently discussed trends in the field at a Piper Jaffray investment conference in New York.
Thomas Errico, M.D., a surgeon at 163-bed Hospital for Joint Diseases Orthopedic Institute in New York, offers several reasons for continuing growth in spine procedures.
First, better and more widely available diagnostic tools, including "an MRI scanner on every corner," are helping surgeons get more referrals, Errico says. Second, for many patients, HMO penetration has lowered the financial barrier to such big-ticket surgery. They face a small co-payment instead of a hefty 20% share of the cost under indemnity insurance.
What's more, spine surgeons are getting better at the procedures, and clinical results have improved. As a result, Errico says, "there's less reticence on patients' part to have major surgery."
Finally-and not to be underestimated, he says-"there are an awful lot of spine surgeons out there, and they'll find work."
Technological innovation also is playing a role in the surgical boom.
A bounty of medieval-looking orthopedic implants, made of the latest high-tech materials, has yielded more treatment options for patients.
Beginning in late 1996, surgeons started screwing threaded titanium cages packed with bone chips into the space between bones in the lower back to help vertebrae fuse (August 11, 1997, p. 68). Sales of these cages, which are used in pairs and cost about $5,000 per case, topped $400 million in 1999.
Some surgeons use similar devices made of bone from cadavers, but shortages of donated bone limit the technique. These devices are absorbed by the body as the vertebrae grow together.
Doctors also continue to apply traditional metal plates and complicated systems of hooks and rods to the outside surfaces of bones, especially in the neck, to stabilize them.
The cost of spinal implants is a hot topic, made even more pressing by an increased rate of "360-degree" fusions. In this technique, surgeons typically insert cages on one side of the spine and rods-and-screw systems on the other. Clinical evidence suggests that the combination increases the odds of a successful fusion. But the approach requires twice as much orthopedic hardware, doubling spending on devices, and might not always be medically necessary.
Happily for patients, the future of back treatment might not be surgical at all.
Promising research is being conducted on tissue growth factors that could regenerate worn-out discs.
"The Holy Grail is disc replacement," says John Sherman, M.D., a spine surgeon at the University of Minnesota School of Medicine. But Sherman warns that the technology must be fool-proof before it can be adopted for routine clinical use. If regenerated discs fail, there's no easy way to get them out, he says.
Another surgeon predicts patient demand will force quick adoption of tissue growth factors once they leave the laboratory.
"The threshold for use will be lower than what we've been used to" for other technologies, said Harvinder Sandhu, M.D., a spine surgeon at 138-bed Hospital for Special Surgery in New York.
In the meantime, other biological breakthroughs could make spine fusion more successful. Scientists have isolated certain proteins that cause bone to grow. When these chemicals are combined with dowels made of bone, the result is better fusion faster, according to Sandhu, who has done work in the area.
For all the progress, surgeons remain humbled by the mysterious origin of much back pain.
"All treatments are fraught with failure," says the University of Minnesota's Sherman. "It's still tough to find where the pain is arising."