Article Figures & Data
Figures
- Fig. 1
Coronal CT reconstruction image of the occipital condyle demonstrating that the right occipital condyle (small arrow) is smaller in size than the left occipital condyle (large arrow) and this patient (case 10) manifests torticollis.
- Fig. 2
3D-CTA reconstruction images demonstrating typical cases of anomalous VAs. Left (case 5): The left VA is agenesis and the right VA enters the cranium via the extraspinal canal after exiting the transverse foramen of the axis. Right (case 8): The left VA (arrow head) enters the cranium via the intraspinal canal under the atlas and the right VA (arrow) enters the cranium via the extraspinal canal.
- Fig. 3
Flow diagram of the classification for occipitalization of the atlas.
- Fig. 4
Type 1 (case 2). Preoperative midsagittal (A) and parasagittal (B) CT reconstruction images demonstrating that the atlas is completely fused with the occiput. The medial atlantoaxial joint is semi-dislocated. The lateral atlantoaxial joint (arrow) is severely deformed and the lateral mass is slipped anteroinferiorly against the superior facet of the axis. Postoperative x-ray film (C) and midsagittal CT reconstruction (D) images demonstrating that AAS remains to some degree but a stable bony arthrodesis is obtained.
- Fig. 5
Type 2. Preoperative midsagittal (A) and parasagittal (B) CT reconstruction images demonstrating that case 4 is a complete fusion type and the lateral atlantoaxial joint (arrow) is slightly loose but almost normal in shape. C2-3 fusion is also demonstrated. Postoperative x-ray film (C) and midsagittal CT reconstruction (D) images demonstrating that AAS is reduced and a stable bony arthrodesis is obtained.
- Fig. 6
Type 3. Preoperative sagittal T2-weighted MR image (A) and x-ray film (B) of case 11 associated with rheumatoid arthritis demonstrating subaxial stenosis and subaxial instability but a wide space available for the cord at the CVJ. Postoperative x-ray film (C) demonstrating the cervical spine is successfully realigned and balanced.
Tables
- Table 1
Summary of osseous anomalies and clinical presentation of 12 patients with occipitalization of the atlas.
Case No. Age (yrs), Sex Comorbidity Fusion Type Hypoplastic Occipital Condyle Atlantoaxial Joint Vertebral Fusion Clinical Presentation Medial Lateral 1 51, F partial subluxated (mobile) hyperreflexia, paresthesia (extremities), pain in the nape of the neck 2 47, F complete rt subluxated (irreducible) deformed C2-3 hyperreflexia, paresthesia (occiput, extremities), motorweakness, gait disturbance 3 63, M partial subluxated (irreducible) C5-6 hyperreflexia, paresthesia (extremities), pain in the nape of the neck 4 56, M complete subluxated (mobile) C2-3 hyperreflexia, paresthesia (extremities), gait disturbance 5 63, F complete lt subluxated (irreducible) C2-3 hyperreflexia, paresthesia (occiput, extremities), gait disturbance 6 68, F complete subluxated (irreducible) deformed C2-3 hyperreflexia, paresthesia (extremities), gait disturbance 7 74, M Chiari malformation partial lt hyperreflexia, paresthesia (extremities), gait disturbance 8 46, M complete lt subluxated (irreducible) C2-3 hyperreflexia, paresthesia (extremities), gait disturbance 9 77, F complete subluxated (irreducible) C2-3 hyperreflexia, paresthesia (extremities), gait disturbance 10 66, F partial rt subluxated (irreducible) hyperreflexia, paresthesia (extremities), gait disturbance 11 62, F RA complete hyperreflexia, paresthesia (occiput, extremities), motorweakness, gait disturbance 12 45, F OPLL complete hyperreflexia, paresthesia (extremities), motorweakness, gait disturbance - Table 2
Summary of surgical methods and outcomes in 12 patients with occipitalization of the atlas.
Case No. Surgical Method AAS Outcome Preop. Postop. 1 Occ-C3 PSF and C1 laminectomy subluxated (mobile) reduced improvement 2 Occ-C4 PSF, C1 laminectomy, and C4-6 laminoplasty subluxated (irreducible) not reduced improvement 3 Occ-C3 PSF and C1 laminectomy subluxated (irreducible) reduced improvement 4 Occ-C3 PSF, C1 laminectomy, and C4-6 laminoplasty subluxated (mobile) reduced improvement 5 Occ-C4 PSF and C1 laminectomy subluxated (irreducible) not reduced improvement 6 Occ-C7 PSF and C1 laminectomy subluxated (irreducible) not reduced improvement 7 foramen magnum decompression improvement 8 Occ-C4 PSF and C1 laminectomy subluxated (irreducible) reduced improvement 9 Occ-C5 PSF and C1 laminectomy subluxated (irreducible) reduced improvement 10 Occ-C7 PSF and C1 laminectomy subluxated (irreducible) reduced improvement 11 Occ-T2 PSF improvement 12 Occ-T3 PSF improvement * Occ = Occiput, PSF = posterior spinal fusion
Case No. Fusion Type Morphology of the VA Hypoplastic Side of the Transverse Foramen Course of the V3 Segment of the VA into the Cranium 1 partial rt, hypoplasia both sides: extraspinal canal 2 complete rt, hypoplasia both sides: extraspinal canal 3 partial no laterality both sides: normal 4 complete rt, agenesis rt lt: intraspinal canal under the atlas 5 complete lt, agenesis lt rt: extraspinal canal 6 complete rt, hypoplasia both sides: extraspinal canal 7 partial lt, agenesis lt rt: normal 8 complete no laterality rt: extraspinal canal lt: intraspinal canal under the atlas 9 complete rt, hypoplasia both sides: extraspinal canal 10 partial rt, agenesis rt lt: normal 11 complete rt, hypoplasia both sides: extraspinal canal 12 complete rt, hypoplasia rt both sides: extraspinal canal
In this issue
Jump to section
Related Articles
Cited By...
- No citing articles found.