title: Is removal of the implants needed after fixation of burst fractures of the thoracolumbar and lumbar spine without fusion? a retrospective evaluation of radiological and functional outcomes.
abstract: METHODS
  In this study of patients who underwent internal fixation without fusion for a burst thoracolumbar or lumbar fracture, we compared the serial changes in the injured disc height (DH), and the fractured vertebral body height (VBH) and kyphotic angle between patients in whom the implants were removed and those in whom they were not. Radiological parameters such as injured DH, fractured VBH and kyphotic angle were measured. Functional outcomes were evaluated using the Greenough low back outcome scale and a VAS scale for pain.
  
  
  RESULTS
  Between June 1996 and May 2012, 69 patients were analysed retrospectively; 47 were included in the implant removal group and 22 in the implant retention group. After a mean follow-up of 66 months (48 to 107), eight patients (36.3%) in the implant retention group had screw breakage. There was no screw breakage in the implant removal group. All radiological and functional outcomes were similar between these two groups. Although solid union of the fractured vertebrae was achieved, the kyphotic angle and the anterior third of the injured DH changed significantly with time (p < 0.05).
  
  
  CONCLUSIONS
  The radiological and functional outcomes of both implant removal and retention were similar. Although screw breakage may occur, the implants may not need to be removed.
  
  
  CONCLUSIONS
  Implant removal may not be needed for patients with burst fractures of the thoracolumbar and lumbar spine after fixation without fusion. However, information should be provided beforehand regarding the possibility of screw breakage.
authors.affiliation: Taipei Veterans General Hospital, No.201, Sec. 2, Shipai Rd, Taipei, 11217, Taiwan.
authors.forename: P-H
authors.initials: PH
authors.lastname: Chou
authors.affiliation: Taipei Veterans General Hospital, No.201, Sec. 2, Shipai Rd, Taipei, 11217, Taiwan.
authors.forename: H-L
authors.initials: HL
authors.lastname: Ma
authors.affiliation: Taipei Veterans General Hospital, No.201, Sec. 2, Shipai Rd, Taipei, 11217, Taiwan.
authors.forename: C-L
authors.initials: CL
authors.lastname: Liu
authors.affiliation: Taipei Veterans General Hospital, No.155, Sec.2, Linong Street, Taipei, 11217, Taiwan.
authors.forename: S-T
authors.initials: ST
authors.lastname: Wang
authors.affiliation: Taipei Veterans General Hospital, No.201, Sec. 2, Shipai Rd, Taipei, 11217, Taiwan.
authors.forename: O K
authors.initials: OK
authors.lastname: Lee
authors.affiliation: Taipei Veterans General Hospital, No.201, Sec. 2, Shipai Rd, Taipei, 11217, Taiwan.
authors.forename: M-C
authors.initials: MC
authors.lastname: Chang
authors.affiliation: Taipei Veterans General Hospital, No.201, Sec. 2, Shipai Rd, Taipei, 11217, Taiwan.
authors.forename: W-K
authors.initials: WK
authors.lastname: Yu
mesh_terms: D000328:Adult; D002493:Central Nervous System Diseases / Q000209:etiology; D020878:Device Removal; D005260:Female; D005593:Fracture Fixation, Internal / Q000295:instrumentation*; D006801:Humans; D007403:Intervertebral Disc / Q000293:injuries / Q000473:pathology; D008159:Lumbar Vertebrae / Q000293:injuries* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology; D019736:Prostheses and Implants; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D013904:Thoracic Vertebrae / Q000293:injuries* / Q000601:surgery; D014057:Tomography, X-Ray Computed
keywords: burst fracture; disc height; implant removal; non-fusion; screw breakage; spine fracture