title: Modified double-door laminoplasty in managing multilevel cervical spondylotic myelopathy: surgical outcome in 520 patients and technique description.
abstract: METHODS
  This is a prospective study on surgical outcomes of double-door laminoplasty in patients with cervical spondylotic myelopathy (CSM).
  
  
  OBJECTIVE
  The purpose of this study was to report the efficacy and safety of modified double-door laminoplasty in a large series of patients with CSM.
  
  
  BACKGROUND
  Laminoplasty is an established procedure for the decompression of multisegmental CSM. However, no report has described the clinical outcomes of laminoplasty for a large number of patients with CSM (>500 patients).
  
  
  METHODS
  Between April 1995 and December 2006, 520 consecutive patients (331 male and 189 female) with CSM who underwent double-door laminoplasty and were followed-up for more than 1 year were enrolled in this study. The mean age was 62.2 years (23 to 93 y), and the mean duration of disease was 20.1 ± 32.0 months. The severity of myelopathy before and after surgery was evaluated according to a scoring system proposed by the Japanese Orthopedic Association for cervical myelopathy (JOA score). Functional improvement was expressed by the recovery rate (RR) of the JOA score.
  
  
  RESULTS
  The average surgery time for laminoplasty was 75.2 ± 23.3 minutes, and the average blood loss was 72.6 ± 84.6 mL. The average follow-up period was 33.3 ± 15.7 months. The mean JOA score was 10.4 ± 2.8 points preoperatively and 13.6 ± 2.5 points at final follow-up. The mean RR was 51.2 ± 2 9.0%. On the basis of RR, we found that the conditions of 493 patients (94.8%) improved (RR, >1%), 20 patients (3.8%) showed no change (RR, 0%), and 7 patients (1.3%) in worse condition (RR, < 0%). The 7 patients deteriorated for reasons (lumbar spinal canal stenosis and cerebral infarction) that were unrelated to CSM.
  
  
  CONCLUSIONS
  Modified double-door laminoplasty is a safe, reliable, and effective procedure for patients with CSM.
authors: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, Aichi, Japan. masaaki_machino_5445_2@yahoo.co.jp
authors: Masaaki
authors: M
authors: Machino
authors: Yasutsugu
authors: Y
authors: Yukawa
authors: Tetsuro
authors: T
authors: Hida
authors: Keigo
authors: K
authors: Ito
authors: Hiroaki
authors: H
authors: Nakashima
authors: Shunsuke
authors: S
authors: Kanbara
authors: Daigo
authors: D
authors: Morita
authors: Fumihiko
authors: F
authors: Kato
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000601:surgery*; D019299:Decompression, Surgical / Q000379:methods*; D005260:Female; D006801:Humans; D007796:Laminectomy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013117:Spinal Cord Compression / Q000601:surgery; D055009:Spondylosis / Q000601:surgery*; D016896:Treatment Outcome