title: Long-term impacts of different posterior operations on curvature, neurological recovery and axial symptoms for multilevel cervical degenerative myelopathy.
abstract: OBJECTIVE
  To investigate the long-term impacts of different posterior operations on curvature, neurological improvement and axial symptoms for multilevel cervical degenerative myelopathy (CDM), and to study the relationship among loss of cervical lordosis, recovery rate and axial symptom severity.
  
  
  METHODS
  We retrospectively reviewed 98 patients with multilevel CDM who had undergone laminoplasty (Group LP, 36 patients), laminectomy (Group LC, 30 patients), or laminectomy with lateral mass screw fixation (Group LCS, 32 patients) between January 2000 and January 2005. Loss of curvature index (CI) was measured according to the preoperative and final follow-up radiographic parameters. The recovery rate was calculated based on the Japanese Orthopedic Association (JOA) score. Axial symptom severity was quantified by Neck Disability Index (NDI).
  
  
  RESULTS
  Analysis of final follow-up data showed significant differences among the three groups regarding loss of CI (F = 41.46, P < 0.001) between preoperative and final follow-up JOA scores (P < 0.001), final follow-up JOA score (F = 7.81, P < 0.001), recovery rate (F = 12.98, P < 0.001) and axial symptom severity (χ (2) = 18.04, P < 0.001). Loss of CI showed negative association with neurological recovery (r = -0.555, P < 0.001) and positive correlation with axial symptom severity (r = 0.696, P < 0.001).
  
  
  CONCLUSIONS
  Excellent neurological improvement was obtained by LP and LCS for patients with multilevel CDM, while loss of CI in groups LP and LC caused a high incidence of axial symptoms. Loss of CI was correlated with poor neurological recovery and axial symptom severity. Lateral mass screw fixation can effectively prevent loss of postoperative cervical curvature and reduce incidence of axial symptoms.
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, 139 Ziqiang Road, 050051 Shijiazhuang, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Du
authors.forename: Linfeng
authors.initials: L
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Shen
authors.forename: Yingze
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Ding
authors.forename: Longxi
authors.initials: L
authors.lastname: Ren
mesh_terms: D000328:Adult; D000368:Aged; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000601:surgery; D019299:Decompression, Surgical / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D020127:Recovery of Function; D012189:Retrospective Studies; D013117:Spinal Cord Compression / Q000150:complications / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods; D013995:Time