Pseudogout of the transverse atlantal ligament: an unusual cause of cervical myelopathy.

BACKGROUND

Calcium pyrophosphate dihydrate deposition in the cervical spine is infrequently symptomatic. This is especially true at the craniocervical junction and upper cervical spine.

CASE REPORT: A 70-year-old previously healthy woman presented with a progressive cervical myelopathy of four months duration.

RESULTS

Examination revealed sensorimotor findings consistent with an upper cervical myelopathy. Radiological studies (plain radiographs, computed tomography, and magnetic resonance imaging) revealed C1-2 instability, and a well-defined extradural 3 cm x 1 cm retro-odontoid mass causing spinal cord compression. Transoral resection of the mass was performed followed by posterior C1-2 stabilization. Histological examination of the mass confirmed calcium pyrophosphate dihydrate deposition. Follow-up examination showed marked clinical and radiological improvement.

CONCLUSION

Although uncommon, calcium pyrophosphate dihydrate deposition disease should be considered in the differential diagnosis of extradural mass lesions in the region of the odontoid.