Design and application of fulcrum screws for atlantoaxial
dislocation

doi:10.3969/j.issn.2095-4344.2509

Abstract

Abstract:

BACKGROUND: Atlantoaxial dislocation often needs surgery for reduction, and posterior screw-rod fixation fusion is the most commonly used surgery. However, the current screw-rod fixation system often increases the reduction effect by increasing the degree of curvature of connecting rod, causing great difficulty of placing rod, which increases the probability of spinal cord injury.

OBJECTIVE: To evaluate the preliminary results of fulcrum screws for atlantoaxial dislocation.

METHODS: From January 2017 to December 2018, 11 patients with atlantoaxial dislocation were selected from General Hospital of Southern Theater Command of PLA, including 4 males and 7 females, at the age of 8-51 years. All patients were treated with posterior screw-rod fixation fusion: Conventional posterior cervical screws were implanted on both sides of the atlas and pivot screws were implanted on both sides of the axis. Atlantodental interval and Japanese Orthopaedic Association scores were recorded before and after operation. Patients were followed up and underwent X-ray and CT to estimate reduction, fixation and bone graft fusion. This study was approved by the Ethics Committee of General Hospital of Southern Theater Command of PLA.

RESULTS AND CONCLUSION: (1) Eleven patients underwent operations successfully without vertebral artery or spinal nerve injury. (2) All patients were followed up for 3-12 months, with an average of 6 months. The symptoms of neck pain and neurological dysfunction were improved in varying degrees. All patients obtained atlantoaxial bone fusion, with an average fusion time of 6 months. (3) At postoperative 1 week, X-ray and CT images showed that atlantoaxial reduction was satisfactory and internal fixation was in good position. (4) Atlantodental interval reduced from preoperatively (6.8±1.5) mm to postoperatively (2.4±0.9) mm (t=17.854, P=0.000). Japanese Orthopaedic Association score increased from preoperatively (14.1±1.3) to postoperatively (15.9±0.9) (t=-10, P=0.000). (5) No complication occurred during follow-up, without recurrence or dislocation. (6) These results showed that using fulcrum screw in posterior screw-rod fixation fusion has an effective reduction for treating atlantoaxial dislocation and its preliminary clinical effects are satisfactory.

Key words:

fulcrum screw, atlantoaxial dislocation, screw-rod, fixed fusion, pull reset, posterior surgery, efficacy, revision

CLC Number:

Ge Su, Zou Xiaobao, Ma Xiangyang, Wang Binbin, Yang Haozhi, Zhang Shuang, Ni Ling, Chen Yuyue, Xia Hong, Wu Zenghui. Design and application of fulcrum screws for atlantoaxial dislocation[J]. Chinese Journal of Tissue Engineering Research, 2020, 24(9): 1348-1352.

Figures/Tables 4

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