Hemodynamic Alteration of the Cervical Venous Circulation in a Patient Suffering From Atlantoaxial Degenerative Osteoarthritis with Subluxation: A Case Report

lence of between 5% and 18%. Only a minority of the patients with osteoarthritis of the atlantoaxial joints become symptomatic and suffer from severe suboccipital pain. Most often, these patients can be successfully treated using conservative methods. However, some of these patients require surgical treatment (1). To the best of our knowledge, there have been no reports on abnormality of the venous circulation at the craniocervical junction and its clinical implications in patients who suffer from degenerative osteoarthritis of the C1-C2 facet joint with atlantoaxial subluxation. We have a keen interest regarding the hemodynamic alterations of the cervical venous plexus in these patients as there was a significant dilatation of the suboccipital cavernous sinus, the internal and external vertebral venous plexuses and the deep cervical veins observed on our patient’s initial MR images. Furthermore, follow-up MR study revealed a significant decrease of the enlarged venous plexuses and deep cervical veins after occipitocervical reduction and fusion. It is also important to consider that the significant dilatation of the cervical venous plexus might be the cause of the vigorous bleeding encountered when dissecting the venous plexus surrounding the C2 nerve root and immediately on top of the C1 lateral mass (2) during surgery.