Double-level myelopathy due to atlantoaxial dislocation (os odontoideum) and subaxial cervical spondylosis with angular kyphosis
- Pars Advanced and Minimally Invasive Medical Manners Research Center, Pars Hospital, Iran University of Medical Sciences, Tehran, Iran.
DOI:10.25259/SNI_104_2020Copyright: © 2020 Surgical Neurology International This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.
How to cite this article: Abolfazl Rahimizadeh, Housain Soufiani, Shaghayegh Rahimizadeh. Double-level myelopathy due to atlantoaxial dislocation (os odontoideum) and subaxial cervical spondylosis with angular kyphosis. 09-May-2020;11:100
How to cite this URL: Abolfazl Rahimizadeh, Housain Soufiani, Shaghayegh Rahimizadeh. Double-level myelopathy due to atlantoaxial dislocation (os odontoideum) and subaxial cervical spondylosis with angular kyphosis. 09-May-2020;11:100. Available from: https://surgicalneurologyint.com/surgicalint-articles/10011/
Background: The surgical management of cervical spondylotic myelopathy (CSM) attributed to os odontoideum (OO with atlantoaxial instability atlantoaxial instability) and subaxial kyphosis together pose significant surgical challenges.
Case Description: An elderly male presented with CSM/myelopathy and severe quadriparesis attributed to an unstable OO and 87° fixed, subaxial cervical kyphosis. After performing a 540° spinal cord decompression with atlantoaxial fixation, the patient did well.
Conclusion: Double-level CSM due to an unstable OO and subaxial kyphosis is rare and typically requires combined 540° decompression and stabilization.
Keywords: Anterior osteotomy, Cervical spine, Fixed cervical kyphosis, Pedicle screw fixation, Smith-Peterson osteotomy
Unstable os odontoideum (OO) with atlantoaxial dislocation and subaxial “draping of the cervical spinal cord” over a kyphotic deformity contributed to dual-level significant cord compression and myelopathy in a 78-year-old male.[
Following a 540° anterior-posterior-anterior decompression and fusion, the patient improved.
A 78-year-old wheel chair bound male developed a severe spastic quadriparesis with sphincter disturbance over a 2-year period. His modified Japanese Orthopedic Association (mJOA) score was 8. Cervical X-rays, MR, and CT studies demonstrated OO instability with subaxial C4-C6 cord compression; there was an accompanying 87° fixed kyphosis [
The patient underwent a C2 to C7 laminectomy with C1 lateral mass screw placements and insertion of bilateral pedicle screws from C2 to C7 bilaterally [
The intraoperative cervical cross-table X-ray ultimately confirmed adequate C1 to C7 instrumentation with a 100° correction of the kyphosis [
Management of OO with instability
The discovery of a symptomatic OO in an elderly patient is rare; we found only 12 such cases in the literature.[
Treatment of subaxial CK
With an angular kyphosis from 30° to 90°, 540° surgery with a combination of anterior-posterior-anterior decompression/fusion may be warranted. In this case, while supine, the patient underwent a two-level corpectomy with three-level anterior osteotomy (C4-C6) (ATO).[
For patients displaying OO/instability and subaxial cervical kyphosis, combined anterior followed by posterior decompression/fusion surgery may be warranted.
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