title: Hemilaminectomy for removal of extramedullary or extradural spinal cord tumors: medium to long-term clinical outcomes.
abstract: OBJECTIVE
  Laminectomy is generally the treatment of choice for removal of spinal tumors. However, it has been shown that laminectomy may cause instability due to damage of posterior elements of the spinal column, which may induce subsequent kyphosis in the future. Therefore, to reduce the risk of deformity and spinal instability after laminectomy, hemilaminectomy has been used. However, the medium to long-term effects of hemilaminectomy on spinal sagittal alignment is not well understood. The present study was performed to evaluate the clinical outcomes, including spinal sagittal alignment of patients, associated with spinal cord tumors treated by surgical excision using hemilaminectomy.
  
  
  METHODS
  Twenty hemilaminectomy operations at our institute for extramedullary or extradural spinal cord tumors in 19 patients were evaluated retrospectively with an average follow-up of 85 months (range, 40-131 months). Neurological condition was evaluated using the improvement ratio of the Japanese Orthopaedic Association Score (JOA score) for cervical, thoracic myelopathy, or back pain, and sagittal alignment by sagittal Cobb angle of the hemilaminectomied area.
  
  
  RESULTS
  The mean improvement ratio of neurological results was 56.7% in the cervical spine (p < 0.01, n = 10), 26.3% in the thoracic spine (not significant, n = 5), and 48.6% in the lumbar spine (NS, n = 5). The sagittal Cobb angle was 4.3 ± 18.0° in the preoperative period and 5.4 ± 17.6° at the latest follow-up, indicating no significant deterioration.
  
  
  CONCLUSIONS
  Hemilaminectomy is useful for extramedullary or extradural spinal cord tumors in providing fair neurological status and restoration of spinal sagittal alignment in medium to long-term follow-up.
authors.affiliation: Department of Orthopaedic Surgery, Gifu University Graduate School of Medicine, Gifu, Japan.
authors.forename: Toshitaka
authors.initials: T
authors.lastname: Naganawa
authors.forename: Kei
authors.initials: K
authors.lastname: Miyamoto
authors.forename: Hideo
authors.initials: H
authors.lastname: Hosoe
authors.forename: Naoki
authors.initials: N
authors.lastname: Suzuki
authors.forename: Katsuji
authors.initials: K
authors.lastname: Shimizu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007796:Laminectomy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013120:Spinal Cord Neoplasms / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult