Stenosis Surgery Should be Limited to Decompression

There is little value in adding fusion to decompression surgery for lumbar spinal stenosis, Wilco C. Peul, M.D.,  Ph.D., and Wouter A. Moojen, M.D., Ph.D., write in a New England Journal of Medicineeditorial accompanying two fusion studies.

To date, there has been little evidence showing that fusion and decompression surgery as one is associated with much benefit, yet the combined procedure is more common today. Decompression with fusion is done in about half of all patients with lumbar spinal stenosis who undergo spine surgery and in 96 percent of patients with spondylolisthesis.

Writing in the April 14 issue of the NEJM, researchers led by Peter F̦rsth, M.D., Ph.D., of Uppsala University in Sweden, found that patients who underwent decompression and fusion surgery, were not better off than patients who underwent decompression surgery alone Рafter a two and five-year analysis.

In the U.S. trial, led by Zoher Ghogawala, M.D., of the Lahey Hospital and Medical Center in Burlington, Mass., researchers found that the addition of lumbar spinal fusion to a laminectomy was associated with a slightly greater improvement in quality of life for patients with spondylolisthesis as compared to laminectomy alone.  [[{"type":"media","view_mode":"media_crop","fid":"47833","attributes":{"alt":"©AlexMit/Shutterstock.com","class":"media-image media-image-right","id":"media_crop_1428205254729","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"5669","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"font-size: 13.008px; line-height: 1.538em; float: right;","title":"©AlexMit/Shutterstock.com","typeof":"foaf:Image"}}]]

In the Swedish Spinal Stenosis Study, Försth randomly assigned 247 patients with and without degenerative spondylolisthesis, to undergo either decompression surgery with fusion surgery or decompression surgery alone. The efficacy of fusion surgery with decompression surgery has never before been shown in clinical trials in this group of patients.

At two years, the researchers found no significant difference between the two treatment groups in the primary outcome. In fact, the mean score on the Oswestry Disability Index (ODI) was 27 in the fusion group and 24 in the decompression-alone group. The ODI score had decreased from baseline by 15 in the fusion group and by 17 in the decompression-alone group.

There was also no significant difference between treatment groups in the results of the six-minute walk test at two years – 397m in the fusion group versus 405m in the decompression-alone group.

“The authors reported that the more technically-advanced decompression with fusion procedure was associated with higher costs, but did not provide improvement with respect to the primary outcome measure, the ODI, or to any other clinical outcome, including walking distance,” wrote Peul and Moojen, both of Leiden University Medical Center in the Netherlands.

In Ghogawala’s study, a randomized controlled trial of 66 patients (mean age, 67 years; 80 percent women) with stable degenerative spondylolisthesis and lumbar spinal stenosis, patients were assigned to either a decompressive laminectomy alone or a laminectomy with posterolateral instrumented fusion. Patients were followed for four years from 2002 to 2009.

“The trial shows a small benefit - just above the minimal clinically important difference – of decompression plus fusion on the primary outcome measure (the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36),” the authors of the editorial wrote. The secondary outcome measure, the Oswestry Disability Index (ODI), showed no significant difference between the treatment groups.

The fusion group had a greater increase in SF-36 physical-component summary scores at two years (15.2 percent) after surgery than did the decompression-alone group (9.5 percent). More blood loss and longer hospital stays occurred in the fusion group than in the decompression-alone group.

In both studies, a second surgery was necessary for many patients. After decompression surgery alone, 21 percent of patients in the Swedish trial and 34 percent in the U.S. trial required a revision surgery. For patients who had both a decompression and fusion surgery, 22 percent of patients in the Swedish trial and 14 percent in the U.S. trial required a follow-up surgery.

“The moderate difference in SF-36 score in favor of instrumented fusion does not justify the associated higher costs for implants and the longer duration of surgery than those with decompression alone,” the authors of the editorial wrote. “Given that the disease-specific ODI is a better outcome measure for the treatment of spinal stenosis than the general SF-36, the fact that both trials showed that the improvements in the scores on the ODI did not differ significantly between the two surgical approaches suggests that the costlier approach of instrumented fusion does not add value for patients.”

Recommendations from the authors of the NEJM editorial:

“Both studies also show that, for most patients, stenosis surgery should be limited to decompression when no overt instability is present. Evidence from the trials by Försth et al and Ghogawala et al suggests that fusion for the treatment of stenosis is no longer the best practice and that its use should be restricted to patients who have proven spinal instability, as confirmed on flexion–extension radiographs; vertebral destruction caused by trauma, tumors, infections, or spinal deformities, such as congenital spondylolisthesis or adult scoliosis or neuroforamen stenosis with compressed exiting nerves caused by postsurgical disk collapse,” Peul and Moojen wrote.

References:

Wilco C. Peul, M.D., Ph.D., and Wouter A. Moojen, M.D., Ph.D. “Fusion for Lumbar Spinal Stenosis - Safeguard or Superfluous Surgical Implant?” The New England Journal of Medicine. DOI: 10.1056/NEJMe1600955.

Peter Försth, M.D., Ph.D., Gylfi Ólafsson, M.Sc., et al. “A Randomized, Controlled Trial of Fusion Surgery for Lumbar Spinal Stenosis,” The New England Journal of Medicine. DOI: 10.1056/NEJMoa1513721  

Zoher Ghogawala, M.D., James Dziura, Ph.D., et al. “Laminectomy plus Fusion versus Laminectomy Alone for Lumbar Spondylolisthesis,” The New England Journal of Medicine. DOI: 10.1056/NEJMoa1508788