Cable-dragged reduction/cantilever beam internal fixation and fusion for the treatment of reversible and irreducible atlantoaxial dislocation

English Keywords:Posterior  Atlantoaxial dislocation  Cantilever beam  Cable dragged reduction  Clinical effect

English Abstract:

  【Abstract】 Objectives: To investigate the clinical outcomes of cable-dragged reduction/cantilever beam internal fixation and fusion for the treatment of reversible and irreducible atlantoaxial dislocation. Methods: From January 2010 to December 2018, 25 cases with atlantoaxial dislocation were surgically treated in our hospital，including 15 males and 10 females with an average age of 49.6±8.8(range, 21-72) years old． All patients presented with varying degrees of limb numbness and weakness before surgery. 12 cases were reversible atlantoaxial dislocation, 13 cases were irreducible atlantoaxial dislocation, which were diagnosed by dynamic X-ray of cervical spine and continuous skull traction before surgery. The cable-dragged reduction/cantilever beam internal fixation and fusion was performed on all the patients． Through the preoperative and postoperative JOA score to evaluate nerve functional restoration, atlantodental interval(ADI) and cervicomedullary angle(CMA) which preoperative and postoperative imaging measurements were performed, were used to evaluate the reduction of atlantoaxial dislocation. Results: All patients were followed up for 18 months on an average(range 12-96 months)． JOA scores were 13.7±1.4, 14.8±1.6 and 15.2±1.3 at 1 week, 6 months and final follow-up after surgery, which were significantly improved compared with the preoperative scores 9.1±1.5(P<0.05). The imaging of postoperative follow-up indicated the atlantoaxial dislocation, which achieved satisfactory reduction. ADI were 2.3±0.3mm, 2.3±0.5mm and 2.4±0.6mm at 1 week, 6 months and final follow-up after surgery, which were significantly improved compared with the preoperative 6.5±0.9mm(P<0.05). CMA were 153.9°±7.3°, 153.4°±7.6° and 152.7°±7.8° at 1 week, 6 months and final follow-up after surgery, which were significantly improved compared with the preoperative 121.8°±5.1°(P<0.05). One case was found the cable cut to the posterior arch of atlas which not fractured at follow-up. No internal fixation screw loosening, fracture and all cases achieved good posterior osseous fusion. Conclusions: Cable-dragged reduction/cantilever beam internal fixation and fusion has the advantages of fixed firm, lower risk and satisfactory reduction． It is reliable and effective for reversible and irreducible atlantoaxial dislocation.