Comparative Study of Surgical Outcomes of Occipitocervical and Atlantoaxial Fusion for Retro-Odontoid Pseudotumor

World Neurosurg. 2023 Oct:178:e230-e238. doi: 10.1016/j.wneu.2023.07.038. Epub 2023 Jul 20.

Abstract

Objective: To compare the surgical and radiographic outcomes of occipitocervical fusion (OCF) with those of atlantoaxial fusion (AAF) in patients with cervical myelopathy caused by retroodontoid pseudotumors (ROPs).

Methods: This retrospective, comparative study included 26 patients; 12 underwent occipitocervical fusion (OCF) (group O) and 14 retroodontoid pseudotumor (AAF) (group A) with a minimum 2-year follow-up. Neurologic outcomes were evaluated using the Japanese Orthopedic Association (JOA) score. Radiologic assessment included the maximum anteroposterior (AP) diameter of the anteroposterior-retroodontoid pseudotumor (AP-ROP), C2-7 angle, O-C2 angle, C1-2 angle, atlantodental interval (ADI), range of motion (ROM) of the ADI, C2-C7 sagittal vertical axis (C2-7 SVA), and T1 slope. Global spinal alignments (pelvic incidence [PI] minus lumbar lordosis [LL] [PI-LL], pelvic tilt, sacral slope, and C7 sagittal vertical axis) were also compared between the groups.

Results: Both groups had equally good clinical outcomes with equal complication rates. Three patients had a three-level fusion, 5 cases had a four-level fusion, and 4 cases had more than five-level fusion in group O. All cases had a single-level fusion in group A. Surgical time was significantly shorter in group A. AP-ROP was significantly downsized postoperatively in both groups and was more prominent in group O. C2-7 SVA was significantly increased and C2-7A ROM was significantly reduced in group O at the final follow-up. The PI-LL showed a significant increase in group O at the final follow-up.

Conclusions: Although OCF and AAF were similarly effective for cervical myelopathy with ROP, AAF was less invasive, and spinal alignment was better maintained postoperatively in AAF than OCF.

Keywords: Atlantoaxial fusion; Cervical myelopathy; Occipitocervical fusion; Retroodontoid pseudotumor.

MeSH terms

  • Cervical Vertebrae / diagnostic imaging
  • Cervical Vertebrae / pathology
  • Cervical Vertebrae / surgery
  • Humans
  • Lordosis* / surgery
  • Odontoid Process* / diagnostic imaging
  • Odontoid Process* / surgery
  • Retrospective Studies
  • Spinal Cord Diseases* / pathology
  • Spinal Fusion*
  • Treatment Outcome

Supplementary concepts

  • Atlanto-Axial Fusion