Occipital neuralgia reavealing an atlantoaxial subluxation in an ankylosing spondylitis patient

Occipital neuralgia is a peripheral neuropathy of the neck and head characterized by "unilateral paroxysmal headache of cervical origin", caused mostly by irritation or of the posterior large occipital nerve. We report the case of a patient with known history of axial and peripheral spondyloarthritis presenting with an unremitting right sided headache evolving for 2 months before examination. The Aetiological research revealed an atlantoaxial subluxation combining vertical and rotatory movements. The patient was surgically treated with C1/C2 laminectomy, an enlargement of the magnum canal and an occipito cervical arthrodesis reinforced posteriorly by a bone graft. While anterior atloaxoidal subluxation has been widely described in spondyloarthritis especially peripheral ones, vertical and rotatory subluxation has been rare to be seen especially when revealed by an occipital neuralgia.