Application of three-dimensional model in the management of irreducible atlanto-axial dislocation

作者：Lin, Xi; Ai, Fu-Zhi; Yin, Qing-Shui^*; Xia, Hong; Wu, Zeng-Hui; Ma, Xiang-Yang

来源：Acta Orthopaedica et Traumatologica Turcica, 2014, 48(3): 298-302.

DOI：10.3944/AOTT.2014.13.0005

• Anatomic model
• atlanto-axial instability
• atlanto-axial joint
• rapid prototyping

Objective: The aim of this study was to describe the application of the rapid prototyping (RP) life-size 3-dimensional model used to improve accuracy of screw insertion in irreducible atlanto-axial dislocation (IAD).
Methods: The study included 10 patients with IAD. All patients were assessed using the Japanese Orthopedic Association (JOA) score. Radiographs, MRI and CT were conducted during the preoperative and postoperative procedure. A 3D RP model was created for each patient. The model was used to obtain detailed information of each pedicle and used as an intraoperative reference. Assisted by the model, transoral atlanto-axial reduction plate fixation was performed in each case.
Results: The average operation time was 145 (range: 90 to 180) minutes and average blood loss was 120 (range: 60 to 250) ml. JOA scores improved after surgery. All 40 transoral pedicle/lateral mass screws were placed without serious complications or internal fixation failure. Postoperative radiographs and CT scan showed 38 transoral pedicle/lateral mass screws located in the pedicle tracts. Satisfactory reduction was achieved in 95% of screws. Two screws perforated the lateral wall of the C2 pedicles in an extremely narrow pedicle case. No neurologic sequelae or vertebral artery injury were detected.
Conclusion: The RP technique is effective and reliable in achieving an accurate and safe screw insertion during IAD surgery, especially in anatomically abnormal cases.

• 出版日期2014
• 单位福建省立医院