title: Implant removal after percutaneous short segment fixation for thoracolumbar burst fracture : does it preserve motion?
abstract: OBJECTIVE
  The purpose of this study was to evaluate the efficacy of implant removal of percutaneous short segment fixation after vertebral fracture consolidation in terms of motion preservation.
  
  
  METHODS
  Between May 2007 and January 2011, 44 patients underwent percutaneous short segment screw fixation due to a thoracolumbar burst fracture. Sixteen of these patients, who underwent implant removal 12 months after screw fixation, were enrolled in this study. Motor power was intact in all patients, despite significant vertebral height loss and canal compromise. The patients were divided into two groups by degree of osteoporosis : Group A (n=8), the non-osteoporotic group, and Group B (n=8), the osteoporotic group. Imaging and clinical findings including vertebral height loss, kyphotic angle, range of motion (ROM), and complications were analyzed.
  
  
  RESULTS
  Significant pain relief was achieved in both groups at final follow-up versus preoperative values. In terms of vertebral height loss, both groups showed significant improvement at 12 months after screw fixation and restored vertebral height was maintained to final follow-up in spite of some correction loss. ROM (measured using Cobb's method) in flexion and extension in Group A was 10.5° (19.5/9.0°) at last follow-up, and in Group B was 10.2° (18.8/8.6°) at last follow-up. Both groups showed marked improvement in ROM as compared with the screw fixation state, which was considered motionless.
  
  
  CONCLUSIONS
  Removal of percutaneous implants after vertebral fracture consolidation can be an effective treatment to preserve motion regardless of osteoporosis for thoracolumbar burst fractures.
authors.affiliation: Department of Neurosurgery, Heori Sarang Hospital, Daejeon, Korea.
authors.forename: Hyeun Sung
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Seok Won
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Chang Il
authors.initials: CI
authors.lastname: Ju
authors.affiliation: Department of Neurosurgery, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Hui Sun
authors.initials: HS
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Sung Myung
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, Korea.
authors.forename: Dong Min
authors.initials: DM
authors.lastname: Kim
keywords: Fusion; Percutaneous; Removal