A new free-hand pedicle screw placement technique with reference to the supraspinal ligament.
We sought to compare the safety and accuracy of a new free-hand pedicle screw placement technique to that of the conventional technique. One hundred fifty-three consecutive adult patients with simple fracture in the thoracic or/and lumbar spine were alternately assigned to either the new free-hand or the conventional group. In the new free-hand technique group, preoperative computerized tomography (CT) images were used to calculate the targeted medial-lateral angle of each pedicle trajectory and the pedicle screw was inserted perpendicular to the correspond-ing supraspinal ligament. In the conventional technique group, the medial-lateral and cranial-caudal angle of each pedicle trajectory was determined by intraoperatively under fluoroscopic guidance. The accuracy rate of pedicle screw placement, the time of intraoperative fluoroscopy, the operating time and the amount of blood loss during operation were respectively compared. All screws were analyzed by using intraoperative radiographs, intraoperative triggered electromyography (EMG) monitoring data, postoperative CT data and clinical outcomes. The accuracy rate of pedicle screw placement in the new free-hand technique group and the conventional technique group was 96.3% and 94.2% (P < 0.05), respectively. The intraoperative fluoroscopy time of the new technique group was less than that of the conventional technique group (5.37 seconds vs. 8.79 seconds, P < 0.05). However, there was no statistical difference in the operating time and the amount of blood loss during operation (P > 0.05). Pedicle screw placement with the free-hand technique which keeps the screw perpendicular to the supraspinal ligament is an accurate, reliable and safe technique to treat simple fracture in the thoracic or lumbar spine.
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Juming
J
Li
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Hong
H
Zhao
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Hao
H
Xie
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Lipeng
L
Yu
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Jifu
J
Wei
Department of radiology, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Min
M
Zong
Department of Statistics, Nanjing Medical University. Nanjing, Jiangsu 210029, China.
Feng
F
Chen
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Ziqiang
Z
Zhu
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Ning
N
Zhang
Department of Orthopaedics, the First Affiliated Hospital of Nanjing Medical University. Nanjing, Jiangsu 210029, China;
Xiaojian
X
Cao
anatomy reference; pedicle screw placement; radiation exposure; spine fracture; supraspinal ligament