KIMMERLE’S ANOMALY AS A FACTOR OF CERVICOGENIC HEADACHE AND VESTIBULO-COORDINATIVE DISORDERS: A CLINICAL CASE AND LITERATURE REVIEW

Аннотация

Background. Kimmerle’s anomaly, also known as ponticulus posticus or arcuate foramen of the atlas, is a congenital or acquired osseous bridge over the groove of the vertebral artery on the posterior arch of C1. Although it is frequently detected incidentally, in selected patients it may participate  in  vertebral  artery  irritation,  extravascular  compression,  cervicogenic  headache  and vestibulo-coordinative dysfunction. 
Methods. A  single-patient  clinical  observation  was  combined  with  a  focused  narrative literature review. The diagnostic work-up included cervical magnetic resonance imaging, multislice computed tomography with three-dimensional reconstruction, computed tomography angiography and duplex Doppler ultrasonography of the vertebral arteries with rotational functional tests. 
Results. A 34-year-old patient presented with recurrent occipital headache, dizziness, tinnitus, gait unsteadiness and symptom exacerbation during head rotation. Imaging revealed a complete right- sided arcuate foramen of C1 with close topographic relationship to the V3 segment of the vertebral artery. Functional Doppler testing demonstrated rotation-dependent reduction of vertebral artery flow velocity. Differential diagnosis excluded vestibular migraine, benign paroxysmal positional vertigo, atherosclerotic vertebrobasilar insufficiency, isolated cervical osteochondrosis and craniovertebral instability. 
Conclusion. Symptomatic Kimmerle’s  anomaly should not  be interpreted as  an isolated radiological variant. Its clinical significance emerges only when structural C1 anatomy, reproducible cervico-vestibular symptoms, positional vascular changes and exclusion of competing vestibular, vascular and cervical disorders are evaluated together in a multidisciplinary and dynamically verified diagnostic model before rational treatment planning decisions are made.
Keywords: Kimmerle’s  anomaly,  ponticulus  posticus,  arcuate  foramen,  cervicogenic headache, vertebral artery, vertebrobasilar insufficiency, dizziness, tinnitus, cervical spine, computed tomography angiography, Doppler ultrasound.