title: Laminoplasty with preservation of posterior cervical elements: surgical technique.
abstract: OBJECTIVE
  We have developed a modified laminoplasty procedure that preserves the posterior cervical elements, and we have used it to treat multilevel cervical canal stenosis, with or without spondylotic changes, in 30 patients.
  
  
  METHODS
  In this procedure, the posterior bony elements, such as the spinous processes, are not completely detached from the ligaments and musculature and are repositioned in the midline, to maintain normal cervical anatomic relationships. Thirty patients (mean age, 55.2 yr) were registered and evaluated in this study, with a mean follow-up period of 18.1 months, between November 1995 and October 2000. The rates of bony union of the reconstructed laminae and alignment of the cervical spine were assessed by using computed tomographic scans and lateral radiographs.
  
  
  RESULTS
  All patients except one noted some improvement in sensation, motor function, or both. Changes in spinal curvature were noted for two patients for whom a kyphotic deformity had developed before surgery (because of S-shaped or straight curvature). The average decrease in the range of motion was 7.26 degrees. Estimated rates of bony fusion at the sites of the gutters, spacers, and spinous processes were 94.6, 62.3, and 86.6%, respectively. A stable bony arch was assumed to be achieved with bony fusion at the gutters on the hinge side, as well as the spinous processes, approximately 6 months after surgery.
  
  
  CONCLUSIONS
  Our new technique of cervical laminoplasty preserves the posterior musculature and bony elements. This new procedure also helps maintain correct spinal alignment.
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, 3-25-8 Nishishinbachi, Minato-ku, Tokyo, Japan. tani@jikei.ac.jp
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tani
authors.forename: Akira
authors.initials: A
authors.lastname: Isoshima
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nagashima
authors.forename: Robert
authors.initials: R
authors.lastname: Tomohiko Numoto
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Abe
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007796:Laminectomy / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D011183:Postoperative Complications / Q000175:diagnosis; D011446:Prospective Studies; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D013117:Spinal Cord Compression / Q000175:diagnosis / Q000601:surgery*; D013128:Spinal Osteophytosis / Q000175:diagnosis / Q000601:surgery*; D013130:Spinal Stenosis / Q000175:diagnosis / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome