title: Indirect spinal canal decompression in burst fractures treated with pedicle screw instrumentation.
abstract: METHODS
  Prospective evaluation of spinal canal areas in 67 consecutive burst fractures between T12 and L2 treated by reduction and stabilization with a pedicle fixator.
  
  
  OBJECTIVE
  Assessment of the efficacy of "indirect" spinal canal decompression in a large series of burst fractures.
  
  
  BACKGROUND
  Up to 50% of burst fractures cause neurologic impairment. Reduction and posterior instrumentation is the most common surgical treatment. This also reduces spinal canal encroachment by indirect decompression. No consensus exists as to the consistency and adequacy of such indirect decompression.
  
  
  METHODS
  Spinal canal areas were measured on preoperative and postoperative computed tomography scans. The degree of encroachment was compared with clinical and radiographic variables for possible correlation.
  
  
  RESULTS
  Spinal canal encroachment was more severe among patients with neurologic deficits than among the neurologically intact. Postoperatively, mean encroachment was reduced from 35% to 12% at T12, from 37% to 17% at L1, and from 52% to 35% at L2. Loss (and postoperative restoration) of anterior vertebral height correlated best with the degree of canal encroachment (and its reduction), especially in Denis Type A burst fractures. In Denis Type B fractures, canal compromise usually was less severe and fragment reduction better in patients older than 40 years of age than in younger patients.
  
  
  CONCLUSIONS
  Indirect decompression in burst fractures averages about half of the preexisting encroachment. Results are usually better at T12 and L1 than at L2. Additional or secondary decompression is rarely indicated if these fractures are treated early and by experienced surgeons. Burst Type B fractures in patients older versus younger than 40 years of age differ in many respects.
authors.affiliation: Department of Orthopaedic Surgery, University Hospital, Uppsala, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Sjostrom
authors.forename: G
authors.initials: G
authors.lastname: Karlstrom
authors.forename: P
authors.initials: P
authors.lastname: Pech
authors.forename: W
authors.initials: W
authors.lastname: Rauschning
mesh_terms: D000328:Adult; D000368:Aged; D001863:Bone Screws; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D013115:Spinal Canal / Q000000981:diagnostic imaging / Q000601:surgery*; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed