title: Use of computed tomographic reconstruction to establish the ideal entry point for pedicle screws in idiopathic scoliosis.
abstract: OBJECTIVE
  To determine the ideal entry point for individual pedicle screw in the surgical treatment of idiopathic scoliosis using computed tomographic (CT) three-dimensional (3D) reconstruction.
  
  
  METHODS
  Twenty patients with moderate or severe idiopathic scoliosis from two groups received surgical treatment using "Free Hand technique" and "Assisted Free Hand technique". Computed tomographic scanning with 3D reconstruction of the thoracic and lumbar spine was conducted to determine the entry point and to evaluate the placement accuracy.
  
  
  RESULTS
  The accuracy of placement was 88.2% in convexity and 84.5% in concavity for the "Free Hand" group, and 94.1% in convexity and 94% in concavity for the "Assisted Free Hand" group. Evidence showed that "Assisted Free Hand" group had higher accuracy when screws were placed in the thoracic spine (P = 0.02), while no obvious difference was seen in the lumbar spine placement (P = 0.47).
  
  
  CONCLUSIONS
  We conclude that in the surgical treatment of severe scoliosis, individual screw placement guided by entry points determined by CT reconstruction can result in improved accuracy and ease of the procedure.
authors.affiliation: Department of Orthopedics, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
authors.forename: Peiqiang
authors.initials: P
authors.lastname: Su
authors.forename: Wentong
authors.initials: W
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Peng
authors.forename: Anjing
authors.initials: A
authors.lastname: Liang
authors.forename: Kaili
authors.initials: K
authors.lastname: Du
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Huang
mesh_terms: D000293:Adolescent; D001863:Bone Screws / Q000592:standards*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D016268:Internal Fixators / Q000592:standards; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008297:Male; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D011300:Preoperative Care / Q000379:methods*; D019919:Prosthesis Implantation / Q000379:methods; D019651:Plastic Surgery Procedures / Q000295:instrumentation / Q000379:methods; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*; D013131:Spine / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult