摘要
Atlantoaxial instability (AAI) is a common but potentially severe complication in pediatric patients with Down syndrome, while its surgical characteristics and outcomes remain understudied compared with non-Down syndrome populations. To compare the clinical presentation, radiological features, surgical strategies, and postoperative outcomes of AAI between pediatric patients with Down syndrome and matched non-Down syndrome controls. A retrospective case-match study was conducted, including 15 patients with Down syndrome along with AAI who underwent surgical atlantoaxial arthrodesis between 2009 and 2022. Each case was matched with two non-Down syndrome controls by age, sex, and AAI severity. The patients were divided into two groups: the Down syndrome group (group DS) and the control group (group C). Data included clinical presentation, radiographic parameters [atlantodental interval (ADI) and space available for the spinal cord (SAC)], surgical approach, complications, and fusion rates were compared between the two groups. Patients with Down syndrome exhibited a higher incidence of neurological symptoms (12/15, 80%) compared with controls (5/30, 16.7%) (P < 0.05). Os odontoideum was more common in patients with Down syndrome (10/15, 66.7%), while rotatory dislocation was more common in patients with non-Down syndrome (9/30, 30%); nine (60%) in group DS and one (2.9%) in group C had a high-signal area on MRI. Preoperative ADI was larger for group DS compared with group C (9.0 vs. 7.4 mm; P < 0.01). The ADI and SAC were significantly corrected and were comparable at the last follow-up. Preoperative Japanese Orthopaedic Association scores were significantly smaller in group DS compared with group C (13.3 vs. 16.5; P < 0.01). Neurological symptoms were significantly improved in all patients at the last follow-up. All included patients underwent posterior atlantoaxial screw-rod fixation and fusion. Only two patients suffered superficial wound infection at the iliac bone area, and another patient in the neck (20%), and no complications occurred in group C. Solid fusion was shown in all patients by the time of the last follow-up. Pediatric patients with AAI often have os odontoideum and hypoplasia of the dental process. Posterior atlantoaxial screw-rod fixation can result in good fusion and neurological function recovery.