A 30 yo male presented with short history spastic quadriparesis and sensory loss.
No history of trauma.
No any known caugulopathy.
RA factor negative.
On admission MRI Cervical spine:
An extra medullary cyst iso intense to Csf causing significant cord compression.
No obvious extension out of adjacent neural foramen.
No any bony spinal canal remodelling.
No any adjacent osseous involvement or altered marrow signals.
No any associated abnormal soft tissue.
Cyst non enhancing on post contrast. Normal enhancing epidural venous plexus noted.
Near complete excision of cyst done by left side posterior laminectomy, appeared extra dural on table. Histopathological diagnosis : Synovial Cyst.
Retrodental Cervical Synovial Cyst
Spinal synovial cysts are generally found in the lower lumbar spine. Synovial cysts of the cervical spine are
extremely rare. Retro dental / atlanto axial synovial cyst to the best of my knowledge, only thirty-five cases have been documented in the literature.
Often there is an associated CV junction bony abnormalies like hypoplastic dense, Atalnto dental instblity or os odontoideum is reported.
In our case hypo plastic dense with possible atlantoaxial instability appears to be the cause of excess
stress might have produced the synovial cyst.
Presenting symptoms CV Junction usually include signs of cervical myelopathy secondary to cord compression. Treatment is surgical to decompress cord and stabilizing CV junction.