Outcome after less-invasive decompression of lumbar spinal stenosis: a randomized comparison of unilateral laminotomy, bilateral laminotomy, and laminectomy

Claudius ThoméDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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Dimitris ZevgaridisDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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Olaf LehetaDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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Hansjörg BäznerDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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Christiane Pöckler-SchönigerDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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Johannes WöhrleDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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Peter SchmiedekDepartments of Neurosurgery, Neurology, and Neuroradiology, University Hospital Mannheim, Faculty for Clinical Medicine of the Karl-Ruprecht-University of Heidelberg, Mannheim; Department of Radiology, Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany

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129–141
Volume/Issue:
Volume 3: Issue 2
DOI link:
https://doi.org/10.3171/spi.2005.3.2.0129
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Object

Recently, limited decompression procedures have been proposed in the treatment of lumbar stenosis. The authors undertook a prospective study to compare the safety and outcome of unilateral and bilateral laminotomy with laminectomy.

Methods

One hundred twenty consecutive patients with 207 levels of lumbar stenosis without herniated discs or instability were randomized to three treatment groups (bilateral laminotomy [Group 1], unilateral laminotomy [Group 2], and laminectomy [Group 3]). Perioperative parameters and complications were documented. Symptoms and scores, such as visual analog scale (VAS), Roland—Morris Scale, Short Form—36 (SF-36), and patient satisfaction were assessed preoperatively and at 3, 6, and 12 months after surgery.

Adequate decompression was achieved in all patients. The overall complication rate was lowest in patients who had undergone bilateral laminotomy (Group 1). The minimum follow up of 12 months was obtained in 94% of patients. Residual pain was lowest in Group 1 (VAS score 2.3 ± 2.4 and 4 ± 1 in Group 3; p < 0.05 and 3.6 ± 2.7 in Group 2; p < 0.05). The Roland—Morris Scale score improved from 17 ± 4.3 before surgery to 8.1 ± 7, 8.5 ± 7.3, and 10.9 ± 7.5 (Groups 1–3, respectively; p < 0.001 compared with preoperative) corresponding to a dramatic increase in walking distance. Examination of SF-36 scores demonstrated marked improvement, most pronounced in Group 1. The number of repeated operations did not differ among groups. Patient satisfaction was significantly superior in Group 1, with 3, 27, and 26% of patients unsatisfied (in Groups 1, 2, and 3, respectively; p < 0.01).

Conclusions

Bilateral and unilateral laminotomy allowed adequate and safe decompression of lumbar stenosis, resulted in a highly significant reduction of symptoms and disability, and improved health-related quality of life. Outcome after unilateral laminotomy was comparable with that after laminectomy. In most outcome parameters, bilateral laminotomy was associated with a significant benefit and thus constitutes a promising treatment alternative.

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Contributor Notes

Address reprint requests to: Claudius Thomé, M.D., Department of Neurosurgery, University Hospital Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1, 68167 Mannheim, Germany. email: claudius.thome@nch.ma.uni-heidelberg.de.
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