Journal List > J Korean Orthop Assoc > v.50(5) > 1013402

Song, Ham, Ko, and Lee: Stress Fracture of the Anterior Atlas Arch Following C1 Posterior Arch Resection for Cervical Myelopathy with Retro-Odontoid Pseudotumor


Atlas fracture accounts for 1% to 3% of all spinal column injuries and 10% of cervical spine fractures, and is most frequently caused by motor vehicle accidents and falls. Only a few cases involving complications after surgical treatment have been reported. We present a case of anterior atlas arch stress fracture accompanied by worsening neurologic symptoms following atlas posterior arch resection for cervical myelopathy with retro-odontoid pseudotumor.

Figures and Tables

Figure 1

Lateral cervical radiographs showing severe degenerative spondylosis, kyphosis and instability at C1-C2. The atlanto-dental interval is 5 mm at flexion (A) and reduced at extension (B).

Figure 2

The retro-odontoid pseudotumor and intramedullary hyper-intense lesion of C1 and C2 were observed in sagittal (A) and axial (B) images on T2-weighted magnetic resonance imaging.

Figure 3

Computed tomography scans showing that C1 posterior arch resection was accomplished and that C1 anterior fracture occurred.

Figure 4

No changes of the retro-odontoid pseudotumor and increased intramedullary hyper-intense lesion of C1 and C2 were observed in sagittal (A) and axial (B) images on T2-weighted magnetic resonance imaging.

Figure 5

One year postoperative images (A: anteroposterior view, B: flexion view, C: extension view) showing adequate placement of the implants with good cervical alignment and successful posterior fusion compared with preoperative image (D).



CONFLICTS OF INTEREST The authors have nothing to disclose.


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