title: Minimally invasive cortical bone trajectory screws placement via pedicle or pedicle rib unit in the lower thoracic spine: a cadaveric and radiographic study.
abstract: To evaluate the feasibility of cortical bone trajectory (CBT) screws fixation via pedicle or pedicle rib unit in the cadaveric thoracic spine (T9-T12).
  
  
  
  Computed tomography (CT) images of 100 patients are analyzed by multiplanar reconstruction. Ten cadaveric thoracic spines are used to insert 4.5 × 35.0 mm CBT screws at all levels from T9 to T12.
  
  
  
  Maximal screw length obtained by CT has a tendency to gradually increase from T9 (29.64 mm) to T12 (32.84 mm), and the difference reaches significant level at all levels except T9 versus T10 (P < 0.01). Maximal screw diameter increases from T9 (4.92 mm) to T12 (7.47 mm) and the difference reaches significant level among all levels (P < 0.01). Lateral angle increases from T9 (7.37°) to T12 (10.47°), and the difference reaches significant level among all levels except T11 versus T12. Cephalad angle from T9 to T12 are 19.03°, 22.10°, 25.62° and 27.50° (P < 0.01), respectively. The percentage of the inner and outer pedicle breakage are 2.5 and 22.5 %, respectively. The violation of lateral pedicle wall occurs at T9 and T10, especially for women at T9.
  
  
  
  Both radiographic and cadaveric studies establish the feasibility of CBT screws placement via pedicle or pedicle rib unit in the lower thoracic spine (T9-T12). Furthermore, our measurements are also useful for application of this technique.
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xuan
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China.
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China.
authors.forename: Hai-Ming
authors.initials: HM
authors.lastname: Jin
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China.
authors.forename: Jiao-Xiang
authors.initials: JX
authors.lastname: Chen
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China.
authors.forename: Dao-Liang
authors.initials: DL
authors.lastname: Xu
authors.affiliation: Department of Orthopaedic Surgery, Affiliated Cixi Hospital of Wenzhou Medical University, Cixi, Ningbo, 315300, People's Republic of China.
authors.forename: Hong-Ming
authors.initials: HM
authors.lastname: Xu
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China.
authors.forename: Yao-Sen
authors.initials: YS
authors.lastname: Wu
authors.affiliation: Department of Orthopaedic Surgery, Second Affiliated Hospital of Wenzhou Medical University, 109 Xueyuanxi Road, Wenzhou, 325027, People's Republic of China. xiangyangwang916@qq.com.
authors.forename: Xiang-Yang
authors.initials: XY
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D002102:Cadaver; D000071538:Cortical Bone / Q000000981:diagnostic imaging*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D019637:Orthopedic Procedures / Q000379:methods*; D065289:Pedicle Screws; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed
keywords: Cortical bone trajectory screws; Minimally invasive; Pedicle rib unit; Rescue failed screws; Thoracic pedicle screws