title: Accuracy of free hand pedicle screw installation in the thoracic and lumbar spine by a young surgeon: an analysis of the first consecutive 306 screws using computed tomography.
abstract: METHODS
  A retrospective cross-sectional study.
  
  
  OBJECTIVE
  The purpose of this study is to evaluate the accuracy and safety of free-hand pedicle screw insertion performed by a young surgeon.
  
  
  BACKGROUND
  Few articles exist regarding the safety of the free-hand technique without inspection by an experienced spine surgeon.
  
  
  METHODS
  The index surgeon has performed spinal surgery for 2 years by himself. He performed fluoroscopy-assisted pedicle screw installation for his first year. Since then, he has used the free-hand technique. We retrospectively reviewed the records of all consecutive patients undergoing pedicle screw installation using the free-hand technique without fluoroscopy in the thoracic or lumbar spine by the index surgeon. Incidence and extent of cortical breach by misplaced pedicle screw was determined by a review of postoperative computed tomography (CT) images.
  
  
  RESULTS
  A total of 36 patients received 306 free-hand placed pedicle screws in the thoracic or lumbar spine. A total of 12 screws (3.9%) were identified as breaching the pedicle in 9 patients. Upper thoracic spine was the most frequent location of screw breach (10.8%). Lateral breach (2.3%) was more frequent than any other direction. Screw breach on the right side (9 patients) was more common than that on the left side (3 patients) (p<0.01).
  
  
  CONCLUSIONS
  An analysis by CT scan shows that young spine surgeons who have trained under the supervision of an experienced surgeon can safely place free-hand pedicle screws with an acceptable breach rate through repetitive confirmatory steps.
authors: Department of Neurosurgery, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
authors: Chang-Hyun
authors: CH
authors: Lee
authors: Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors: Seung-Jae
authors: SJ
authors: Hyun
authors: Department of Orthopaedic Surgery, Spine Service, New York Presbyterian Hospital, Columbia University College of Physicians and Surgeons, New York, USA.
authors: Yongjung J
authors: YJ
authors: Kim
authors: Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors: Ki-Jeong
authors: KJ
authors: Kim
authors: Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors: Tae-Ahn
authors: TA
authors: Jahng
authors: Department of Neurosurgery, Spine Center, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors: Hyun-Jib
authors: HJ
authors: Kim
keywords: Accuracy; Lumbar: Free hand; Pedicle screw; Safety; Thoracic