title: Degenerative lumbar spinal stenosis: analysis of results in a series of 374 patients treated with unilateral laminotomy for bilateral microdecompression.
abstract: OBJECTIVE
  Surgical decompression is the recommended treatment in patients with moderate to severe degenerative lumbar spinal stenosis (DLSS) in whom symptoms do not respond to conservative therapy. Multilevel disease, poor patient health, and advanced age are generally considered predictors of a poor outcome after surgery, essentially because of a surgical technique that has always been considered invasive and prone to causing postoperative instability. The authors present a minimally invasive surgical technique performed using a unilateral approach for lumbar decompression.
  
  
  METHODS
  A retrospective study was conducted of data obtained in a consecutive series of 473 patients treated with unilateral microdecompression for DLSS over a 5-year period (2000-2004). Clinical outcome was measured using the Prolo Economic and Functional Scale and the visual analog scale (VAS). Radiological follow-up included dynamic x-ray films of the lumbar spine and, in some cases, computed tomography scans.
  
  
  RESULTS
  Follow-up was completed in 374 (79.1%) of 473 patients--183 men and 191 women. A total of 520 levels were decompressed: 285 patients (76.2%) presented with single-level stenosis, 86 (22.9%) with two-level stenosis, and three (0.9%) with three-level stenosis. Three hundred twenty-nine patients (87.9%) experienced a clinical benefit, which was defined as neurological improvement in VAS and Prolo Scale scores. Only three patients (0.8%) reported suffering segmental instability at a treated level, but none required surgical stabilization, and all were successfully treated conservatively.
  
  
  CONCLUSIONS
  Evaluation of the results indicates that unilateral microdecompression of the lumbar spine offers a significant improvement for patients with DLSS, with a lower rate of complications.
authors: Department of Neurosurgery, Universitià degli Studi di Milano, Istituto IRCCS Galeazzi, Milan, Italy. f.costa@fastwebnet.it
authors: Francesco
authors: F
authors: Costa
authors: Marco
authors: M
authors: Sassi
authors: Andrea
authors: A
authors: Cardia
authors: Alessandro
authors: A
authors: Ortolina
authors: Antonio
authors: A
authors: De Santis
authors: Giovanni
authors: G
authors: Luccarell
authors: Maurizio
authors: M
authors: Fornari
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019299:Decompression, Surgical / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications; D007796:Laminectomy; D008159:Lumbar Vertebrae; D008297:Male; D008866:Microsurgery; D008875:Middle Aged; D010147:Pain Measurement; D011183:Postoperative Complications; D011184:Postoperative Period; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013130:Spinal Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome