The Outcomes of Posterior Arthrodesis for Atlantoaxial Subluxation in Down Syndrome Patients A Meta-Analysis

Study Design: This is a meta-analysis. Objective: To establish rates of (1) neurological complications, (2) bony-related complications, (3) complications delaying recovery, (4) reoperation, and (5) fatalities following posterior cervical arthrodesis in Down syndrome (DS) patients with atlantoaxial subluxation. To determine if presenting symptoms had any relationship to postoperative complications. Summary of Background Data: Posterior arthrodesis is commonly utilized to correct cervical instability secondary to atlantoaxial instability in DS patients. However, there has never been a global evaluation of postoperative complications associated with posterior cervical spinal arthrodesis in DS patients. Methods: A comprehensive search of Medline/PubMed, EMBASE, and Ovid databases between January 1980 and July 2017 was utilized to identify DS patients with atlantoaxial subluxation who underwent posterior cervical arthrodesis. Data were sorted by neurological complications, complications delaying recovery, bony-related complications, reoperations, and fatalities. Patients were sorted into 2 groups based on presentation with or without neurological deficits. Results: Twelve studies met inclusion criteria, including 128 DS patients. Mean age was 13.8 years (range: 6.7-32.7y; 47.8% male). Mean follow-up was 31.7 months (range: 14.9-77mo). All patients underwent primary posterior cervical arthrodesis with an average of 2.5 vertebrae fused. A total of 39.6% of patients had bony-related complications [95% confidence interval (CI), 31.4%-48.5%], 23.3% had neurological deficits (95% CI, 16.6%-31.6%), and 26.4% experienced complications delaying recovery (95% CI, 19.4%-34.9%). The reoperation rate was 34.9% (95% CI, 25.5%-45.6%). The mortality rate was 3.9% (95% CI, 1.5%-9.7%). Neurological complications were 4-fold (P < 0.05) and reoperation was 5.5-fold (P < 0.05) more likely in patients presenting with neurological deficits compared with those without. Conclusions: This study detailed global complication rates of posterior arthrodesis for DS patients, identifying bony-related complications and reoperations among the most common. Patients presenting with neurological symptoms and cervical instability have increased postoperative rates of neurological complications and reoperations than patients with instability alone. Further investigation into how postoperative complications effect patient independence is warranted.