Issue: Issue 5 2006
September 01, 2006
1 min read

JOA scores improved 11 points following lumbar microsurgical decompression

Radiographs show that the spondylolisthesis technique also preserves the facet joints.

Issue: Issue 5 2006
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Japan flagBERGEN, Norway — Japanese investigators found the microsurgical posterior decompression nonfusion technique they used to treat patients with lumbar degenerative spondylolisthesis was safe and effective at 6 years of clinical follow-up.

Surgeons reported a mean postoperative improvement rate in the Japanese Orthopaedic Association (JOA) neurological scores of 65% for the 66 patients they treated, a statistically significant difference, Nobuhiro Tanaka, MD, said.

“The technique was minimally invasive and the clinical results were acceptable when the patients were carefully selected. Microsurgical posterior decompression without fusion can be performed safely as a selected surgical option for lumbar degenerative spondylolisthesis,” Tanaka said in a presentation at the International Society for the Study of the Lumbar Spine 33rd Annual Meeting, here.

Surgeons achieved effective decompression while preserving the facet joints, as seen in this postoperative CT scan.

Image: Tanaka N

Investigators in the departments of orthopaedic surgery at Hiroshima University and Hiroshima General Hospital conducted the study to improve the results reported by other surgeons using standard posterior decompression combined with fusion, a technique many considered optimal for this indication.

Low-grade spondylolisthesis

Surgeons treated 66 patients diagnosed with lumbar degenerative spondylolisthesis with the microsurgical posterior decompression method Tanaka described in his presentation and through a video presentation (36 women, 30 men). The patients’ mean age was 66 years.

The patients they included had radiculopathy combined with low back pain and minimal spinal instability, either grade 1 or 2. Investigators excluded patients with severe low back pain and/or severe spondylitic instability greater than grade 2, and they fused that group’s spines instead. Ultimately, 64 patients had a single level decompression; two patients underwent two-level decompressions. Forty-two patients had posterior laminectomies, 18 had microsurgical decompression with unilateral approach and six underwent endoscopic decompression using a micro-endoscopic discectomy MED system.

“No clinical and radiographic variation was found with an average follow-up period of 6 years,” Tanaka said.

Two-hour procedure

The microscopic technique took an average of 124 minutes to complete. At a mean follow-up of 73 months JOA scores improved from 13 points preop to 24 points postop, he said.

For more information:
  • Tanaka N, Fujimoto Y, Okuda T, et al. Clinical results of microsurgical posterior decompression without fusion for lumbar degenerative spondylolisthesis. #20. Presented at the International Society for the Study of the Lumbar Spine 33rd Annual Meeting. June 14-17, 2006. Bergen, Norway.