title: Incidence of postlaminectomy kyphosis after Chiari decompression.
abstract: METHODS
  In this retrospective study, a 5-year series of a pediatric population undergoing Chiari decompressions is reviewed.
  
  
  OBJECTIVE
  To review the experience with children treated with suboccipital craniectomy and uni- or multilevel cervical laminectomy for Chiari malformation, to determine the incidence of kyphosis and to identify factors predictive of cervical instability.
  
  
  BACKGROUND
  Upper cervical laminectomy in the pediatric population has a significant risk of postoperative kyphosis. To decrease the incidence of this complication, a concerted effort was made to avoid violation of the facet joint during cervical laminectomy.
  
  
  METHODS
  Thirty-two patients (mean age 4.9 years, range 1 day to 18 years) had surgical decompression of Chiari I or II malformations throughout a 5-year period (1989-1994). Radiographs and operative records were analyzed to determine the number of cervical levels decompressed and extent of laminectomy.
  
  
  RESULTS
  Mean follow-up was 3.7 years (range 9 months to 7 years). Only one patient had clinical and radiographic evidence of kyphosis and required C2-C3 fusion. Two others had radiographic signs of mild cervical kyphosis but remained asymptomatic. These three patients had two-level complete laminectomies. Twenty-nine patients had no clinical or radiographic evidence of cervical instability. A mean of three cervical levels were decompressed (range 0-4), including partial laminectomies, complete laminectomies, and one osteoplastic laminotomy to drain a lower cervical syrinx. The overall frequency of kyphosis in this series (9%) was substantially lower than in previous reports. Although the number of cervical levels decompressed did not correlate with cervical instability, the one patient with clinical instability had inadvertent violation of the facet joint, suggesting that overaggressive laminectomy may be a critical factor that predisposes patients to postoperative kyphosis.
  
  
  CONCLUSIONS
  Cervical kyphosis after Chiari decompression is a recognized complication of cervical laminectomy in children, the frequency of which may be decreased by careful attention to operative technique.
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pennsylvania, USA.
authors.forename: M R
authors.initials: MR
authors.lastname: McLaughlin
authors.forename: J B
authors.initials: JB
authors.lastname: Wahlig
authors.forename: I F
authors.initials: IF
authors.lastname: Pollack
mesh_terms: D000293:Adolescent; D001139:Arnold-Chiari Malformation / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007738:Kyphosis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D007796:Laminectomy; D008279:Magnetic Resonance Imaging; D008297:Male; D009333:Neck; D011183:Postoperative Complications; D011184:Postoperative Period; D012189:Retrospective Studies; D013123:Spinal Fusion; D014057:Tomography, X-Ray Computed