Chimney sublaminar decompression for degenerative lumbar spinal stenosis

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>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.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>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.</jats:p> <jats:p>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.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>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.</jats:p></jats:sec>

Spinous Process splitting Laminectomy: Clinical outcome and Radiological analysis of extent of decompression

“…This could probably be because of an anatomically wider canal at L5-S1, thus placing the lateral recesses farther wide apart (also corroborated by higher mean preoperativeinterfacet distance at L5-S1 despite a comparable AP diameter, lateral recess depth and lateral recess angle to other stenosed levels in this series), thus hindering adequate visualisation and limiting the extent of decompression possible through a split spinous approach. As has been previously published, 10,11,24 we believe that effective lateral recess decompression can be obtained by proper retraction of the paraspinal muscles, changing the lateral tilt of the operating table, and approaching the side of decompression from the contralateral side viewing obliquely under the split lamina and paraspinal muscles. Though, this procedure is not effective for treating foraminal stenosis as noted by the radiologic values in our series, foraminal dissection and freeing of the adhesions around the nerve root in the foraminal area may be responsible for the clinical benefit seen.…”

“…Watanabe et al 10 improvised this technique by splitting the spinous process, preserving bilateral paraspinal muscle integrity and performing a complete laminectomy. Lin et al 24 reported a slight modification wherein they preserved the outer one third thickness of the lamina, bent it laterally using an osteotome along with the overlying paraspinal muscles and removed the inner two thirds thickness of the lamina. They minimised paraspinal muscle injury further by preserving their attachment to the laminar surface which was elevated in the original SPSL technique.…”

Iatrogenic spondylolisthesis following laminectomy for degenerative lumbar stenosis: systematic review and current concepts

“…Fifteen of the studies were conducted prospectively 1,5-8, 15,16,21,32,33,35,37,46,47,52 and 9 were conducted retrospectively. 10,14,19,20,27,[38][39][40][41] Postoperative instability was defined variably across studies, including increase in sagittal translation between flexion-extension radiographs by 2 mm, 1,8,14 3 mm, 16 5 mm, 47 5%, 21 or 8%, 19 or an increase in sagittal angulation by more than 15° between flexion and extension.…”

Endoscopic posterior decompression of lumbar canal stenosis

“…The spinal canal was increased to 2-to 6.8-fold (mean 4.2 fold) of the pre-operative size. [26] Although the results of microscopic discectomy using tubular retractor have been found to be safe and effective, [27] there is no report of bilateral decompression using microscopic technique to the best of our knowledge.…”