Atlantoaxial Fixation in Arnold Chiari Malformation Type-1: A Case Series of 10 Patients.

Background: The cranio-vertebral junction (CVJ) encompasses the region between the base of the skull and the upper cervical spine. Anomalies in this area, often associated with Chiari Malformations (CM), can lead to intractable pain, myelopathy, or functional disability, necessitating surgical intervention aimed at decompression, realignment, and stabilization. Aims And Objectives: This prospective observational study evaluates the efficacy of C1-C2 fixation for treating CM with syrinx in patients without Atlantoaxial Dislocation (AAD) or Basilar Invagination (BI). Materials And Methods: Ten adult patients with CM and syrinx underwent atlantoaxial facet stabilization using plate and screw fixation. Pre- and postoperative assessments included Visual Analogue Scale (VAS) scores, syrinx size, and extent of cerebellar herniation. Results: Significant symptomatic improvement was seen, with VAS scores improving from an average of 5.4 preoperatively to 1.9 postoperatively. Syrinx reduction was observed in 90% of cases, and cerebellar herniation regressed in 33.3% of patients. No postoperative complications were reported, and the average hospital stay was 3.5 days. Conclusion: This study supports the hypothesis that C1-C2 instability is central to the pathogenesis of CM and suggests that atlantoaxial fixation, without foramen magnum decompression, is an effective treatment modality.