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Chimney sublaminar decompression for degenerative lumbar spinal stenosis.

OBJECT
The authors evaluated the efficacy and safety of so-called chimney sublaminar decompression, a new technique to decompress the degenerative stenotic lumbar spinal canal without stripping of the paravertebral muscles.


METHODS
Eighteen patients (nine men and nine women whose mean age was 67 years) with symptoms of claudication were selected to undergo chimney sublaminar decompression. The duration of symptoms was greater than 6 months in 17 patients. Two lumbar segments were involved in seven patients, three in eight, and four in the remaining three patients. Central canal stenosis was present in 13 patients, and lateral recess stenosis in five patients. Mild spondylolisthesis was noted in seven patients. All the patients underwent chimney sublaminar decompression. After surgery, mild wound pain developed in 14 patients, moderate wound pain in two, and severe wound pain in two. The postoperative hospital stay was 4 days or fewer in 14 patients. At follow-up examination, excellent, good, and fair outcomes were achieved in 11, five, and two patients, respectively. No patient required a body brace, and no worsening of preexisting spondylolisthesis was detected. The spinal canal was increased to two- to 6.8-fold (mean 4.2-fold) the preoperative size.


CONCLUSIONS
Compared with laminectomy or endoscopic surgery, the aforementioned chimney sublaminar decompression technique was an equally effective and less invasive technique in the treatment of degenerative lumbar canal stenosis.