Bony Stroke on Rheumatoid Arthritis: A Rare Entity or a Missed Diagnosis?

Bone or cartilage anomalies affecting the arteries supplying the brain can be a structural cause of ischemic stroke. Due to their rarity, there is currently no standardized approach for evaluating and treating these so-called bony strokes. We present a case of a 79-year-old woman with a history of cranial settling due to rheumatoid arthritis (RA) and moderate disability, who presented with insidious dizziness and gait disturbances over three weeks. Clinical examination unveiled impaired cognition and discrete left-side dysmetria. Initial head computed tomography (CT) showed signs of a recent stroke within the left posterior inferior cerebellar artery (PICA) territory, with chronic infarctions in the contralateral cerebellum. CT angiography (CTA) identified subocclusive stenosis in the V3 segment of the left vertebral artery (VA), attributed to cranial settling progression. An ultrasonographic study revealed increased flow resistance in both V2 segments, with downstream normalization at the V4 level. A diagnosis of bony stroke was established. This case underscores the significance of considering bone abnormalities as structural causes of ischemic stroke, especially in recurrent cryptogenic events within a dependent territory. This consideration is particularly critical for patients with cognitive impairment, which can obscure accurate diagnoses and delay treatment.