Cervical anterior approach atlantodentoplasty for the treatment of irreducible atlantoaxial dislocation complicated with bony abnormality of atlanto-dental joint / 中华骨科杂志

ABSTRACT

Objective:To evaluate the clinical efficacy of cervical anterior approach atlantodentoplasty for the treatment of irreducible atlantoaxial dislocation complicated with bony abnormality of atlanto-dental joint.Methods:Retrospective analysis was conducted to study the clinical data of 31 patients with irreducible atlantoaxial dislocation complicated with bony abnormality of atlanto-dental joint, including 7 males and 24 females; age ranged from 23 to 74 years, with an average of 49.0±12.0 years. All patients underwent cervical anterior approach soft tissue release, atlantodentoplasty and one-stage posterior occipito-cervical fixation and fusion. Twenty-one patients with atlantodental osteoarthritis underwent simplex atlantodental osteophyte resection, 5 patients with anterior tubercle hypertrophy of atlas and 5 patients with anterior tubercle hypertrophy of atlas and atlantodental osteoarthritis underwent atlantodental osteophyte resection and partial anterior tubercle resection. The operation time and blood loss of anterior procedure and total procedure were recorded. The anterior tubercle thickness (ATT), the atlantodental interval (ADI)were recorded before and 1 week after the operation. The available space of the cord (SAC), clivus-canal angle (CCA), cervicomedullaryangle (CMA), and the Japanese Orthopaedic Association (JOA) scores were recorded before the operation, 1 week, 3 months and 12 months after the operation, and at the last follow-up. The JOA improvement rate at the last follow-up was calculated, the time of postoperative bone graft fusion was recorded, and the complications were observed.Results:All patients were followed up for 12-60 months, with an average of 34.5±13.8 months. The operation time of anterior cervical atlantodentoplasty was 120.9±15.9 min, and the overall operation time was 315.1±31.4 min; The blood loss of anterior procedure was 101.2±31.2 ml, and that of overall procedure was 372.7±56.0 ml. The one week postoperative ATT (7.4±1.6 mm) of patients with anterior tubercle partial resection of atlas was lower than that before operation 10.8±1.5 mm ( t=4.94, P=0.001). The one week postoperative ADI 0.9±1.2 mm decreased compared with the preoperative ADI 8.3±2.2 mm ( t=17.91, P<0.001). The preoperative SAC was 10.4±2.8 mm, which increased to 19.2±3.6 mm one week after operation and 19.4±3.7 mm ( F=41.31, P<0.001) at last follow-up. The preoperative CCA was 119.4°±17.9°, which increased to 142.6°±13.0° one week after operation and 141.6°±12.2° ( F=35.86, P<0.001) at last follow-up. The preoperative CMA was 121.7°±14.1°, which increased to 148.9°±9.4° one week after operation and 149.4°±9.0° ( F=52.07, P<0.001) at last follow-up. The preoperative JOA score was 12.0±2.6, which was 14.3±1.3 one week after operation and 15.9±1.0 ( F=23.81, P<0.001) at last follow-up. JOA improvement rate was 78.9%±17.1%, while 23 cases were excellent (74.2%), 8 cases were good (25.8%), and the excellent and good rate was 100%; Thd fusion time of grafted bone was 5.7±1.5 months with the fusion rate of 100%; There were 12 patients with dysphagia after operation, all of which relieved spontaneously 5-10 days after operation; There were 3 cases of irritating choking after drinking or eating, and 2 cases were gradually alleviated 3-5 days after operation. One case was complicated with aspiration pneumonia due to stubborn choking, which gradually alleviated after 1 month of nasal feeding. No hardware failure or reduction loss, no serious complications such as esophageal injury, cerebrospinal fluid leakage, incision infection or vertebral artery injury occurred. Conclusion:Cervical anterior approach atlantodentoplasty for the treatment of irreducible atlantoaxial dislocation complicated with bony abnormality of atlanto-dental joint can anatomically reduce the atlantoaxial joint, and the clinical effect is satisfactory.