One-stage posterior combined surgery for reducible atlantoaxial dislocation with lower cervical spinal canal stenosis

English Keywords:Atlantoaxial dislocation  Reducible  Lower cervical spinal canal stenosis  Spinal fusion  Laminoplasty  Combined surgery

English Abstract:

  【Abstract】 Objectives: To investigate the clinical effect of one-stage posterior atlantoaxial fixation and fusion combined with unilateral open-door laminoplasty in the treatment of atlantoaxial dislocation with lower cervical spinal canal stenosis. Methods: From June 2010 to December 2017, 21 patients with atlantoaxial dislocation and lower cervical spinal canal stenosis were treated in our hospital by one-stage posterior atlantoaxial screw-rod fixation and fusion combined with unilateral open-door laminoplasty. All the 21 patients had reducible atlantoaxial dislocation. The causes of lower spinal canal stenosis included multisegment cervical disc herniation(9 cases), congenital developmental cervical canal stenosis(6 cases), and ossification of posterior longitudinal ligament(6 cases). The Japanese Orthopaedic Association(JOA) score was adopted to estimate the neurologic status, and the visual analog scale(VAS) score was used to evaluate the degree of occipital neck pain. The atlanto-dental interval(ADI) and lower cervical sagittal diameter(LCSD) were measured before and after the operation. X-ray and CT scan were obtained regularly during the follow-up for evaluation of internal fixation, atlantoaxial reduction, bone graft fusion, and stability of laminoplasty. Results: All the 21 patients were successfully operated with no vascular and nerve injury during the operation. Postoperative incision infection occurred in one patient, which was cured by anti-infection and debridement. The neurological dysfunction and occipital neck pain of all patients were improved to different degrees after operation. The JOA score, VAS score, ADI and LCSD were significantly improved after surgery and at final follow-up(P<0.05). The follow-up period was 12-45 months, with an average of 24.9±9.2 months. During the follow-up period, X-ray and CT scan showed no loosening or fracture of internal fixation, no atlantoaxial redislocation, and no "reclosed-door". All patients obtained atlantoaxial bony fusion in 3-12 months after surgery (an average of 7.0±2.7 months). Conclusions: One-stage posterior atlantoaxial fixation and fusion combined with unilateral open-door laminoplasty is an effective surgical procedure for the treatment of the reducible atlantoaxial dislocation with lower cervical spinal canal stenosis.