Spine fusion yields significant improvements in quality of life

Researchers found that spine fusion outcomes are equivalent to those of hip and knee replacement.

The first stage of a cost-utility analysis has shown that spine fusion provides excellent outcomes, according to Australian researchers.

“Our study has shown that spinal decompression and fusion surgery [for degenerative spondylolisthesis] is able to generate significant and substantial improvements in health-related quality of life (HRQL),” William R. Sears, MBBS, an orthopedic surgeon at Macquarie University in Sydney, told Orthopedics Today. “The improvements are equivalent to published outcomes following hip and total knee joint replacement. [The procedure can] return patients to similar — and probably clinically indiscernible — HRQL levels as age-matched population norms.”

One disorder, one surgery

In a prospective, consecutive case series, Sears and colleagues studied degenerative spondylolisthesis treated with spinal decompression and fusion. They compared these results to those of total joint arthroplasty and to age-matched population norms. They focused on one spine problem and one surgery to eliminate as many of the heterogeneous factors surrounding spine surgery as possible, Sears said.

Clinical inclusion criteria were neurogenic claudication, no previous surgery and failed conservative management. Patients had to have single-level spinal stenosis with investigator-defined unstable grade 1 or 2 degenerative slip.

Two experienced surgeons performed posterior lumbar interbody fusion with an emphasis on correcting the deformity and restoring alignment, Sears said during the North American Spine Society annual meeting.

To measure outcomes, the researchers used the SF-12, a generic measure derived from the SF-36. The SF-12 allows comparison between different health conditions and, in particular, their management.

Although there were only a few published papers on hip (2) and knee replacement (3) in the Australian published statistics, the overall number of patients was significant. Mean age was similar in all studies.

The PCS-12 scores were similar for spines, hips and knees as well as population norms.

“All groups started off significantly disabled … the spines, hips and knees. There was no significant difference in terms of overlaps at last follow-up. They were slightly worse than the population norms but if one looks at the minimal important difference (defined as a difference of more than five points), there was none.”

Sears and colleagues found similar results for the mental component scores.

Health economics data

“This was critically important health economics data, which I'm keenly interested in and NASS is keenly interested in,” session moderator Thomas Faciszewski, MD, said during the question-and-answer session.

Faciszewski, NASS past-president, asked about the durability of spine fusion results.

“It’s a good question,” Sears said. “Dave Polly and Raj Rampersaud looked at 1- and 2-year data. With this study, we took patients out to 5 years, which I think was the longest follow-up. But we haven’t looked uniformly at the later follow-up, which needs to be done.”

Raj Rampersaud said the five-year data from his prospective, matched cohort has shown sustainability with almost 90% follow-up in each cohort.

For more information:
William R. Sears, MBBS, can reached at Macquarie University, 26 Stanhope Road, Killara, Sydney, Australia, NSW 2071; +61-2-9850-4000; fax: +61-2-9850-4010; email: w.sears@mac.com. He is a consultant to and receives royalties from Medtronic (also speaking arrangements, research support and trips/travel).

Reference:
Sears W, McCombe P, Williamson O, White G. Comparison of health-related quality of life following fusion for lumbar degenerative spondylolisthesis with hip and knee joint replacement surgery and with population norms. Paper #15. Presented during the North American Spine Society 23rd Annual Meeting. Oct. 14-18, 2008. Toronto.