title: Shen instrumentation for the management of unstable thoracolumbar fractures.
abstract: METHODS
  A retrospective study was carried out using Shen instrumentation, which is a modified pedicle rod sleeve spinal system, to perform reduction and fusion in patients with unstable thoracolumbar fracture.
  
  
  OBJECTIVE
  To demonstrate that the simple, locally made pedicle rod sleeve instrumentation is as effective as conventional systems in the management of thoracolumbar fractures. The current results are also compared with those reported in the literature.
  
  
  BACKGROUND
  Many instrumentations, such as Harrington, Luque, and Dick, have been used for the management of thoracolumbar fracture in the past 2 decades. Every device has its advantages and disadvantages based on clinical practice and the biomechanical mechanism of reduction.
  
  
  METHODS
  Between January 1991 and December 1995, 96 consecutive patients who had experienced unstable thoracolumbar fractures were treated surgically with Shen instrumentation, which consists of four components: superior pedicle screws, distraction rods, sleeves, and inferior laminar hooks. Of these 96 patients, 76 were male and 20 were female (age range, 16-68 years; mean, 37 years). Thirty patients had partial paraplegia and 38 patients had complete paraplegia, according to the Frankel classification. Injury categories were as follows: 43 burst fractures, 26 flexion-compression fractures, 22 fracture-dislocation injuries, and 5 flexion-distraction injuries.
  
  
  RESULTS
  The average follow-up was 39 months (range, 24-60 months). Kyphotic deformity was corrected from 27.1 degrees before surgery to 4.2 degrees after surgery, translation was reduced from 30.7% to 0%, height of compressed vertebral bodies was restored from 52.3% to 96.5% of the normal height. Computed tomographic evaluation showed that the cross-canal area was restored from 48.1% before to 70.9% after surgery. Improvement of neurologic function of more than one Frankel grade occurred in 90% of patients.
  
  
  CONCLUSIONS
  Based on the understanding of biomechanics and the present clinical results, Shen instrumentation is as efficacious as conventional devices available today and may serve as a cost-effective option for thoracolumbar injuries, especially in a developing country.
authors.affiliation: Department of Orthopaedic Surgery, Naval General Hospital, Beijing, People's Republic of China.
authors.forename: D K
authors.initials: DK
authors.lastname: Ruan
authors.forename: G B
authors.initials: GB
authors.lastname: Shen
authors.forename: H X
authors.initials: HX
authors.lastname: Chui
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D001863:Bone Screws; D005260:Female; D005593:Fracture Fixation, Internal / Q000295:instrumentation*; D006801:Humans; D016268:Internal Fixators; D007738:Kyphosis / Q000601:surgery; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries* / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome