Non-aneurysmal Subarachnoid Hemorrhage Presenting With Isolated Neck and Back Pain: A Rare Case Report.

Subarachnoid hemorrhage (SAH) is defined as bleeding into the subarachnoid space between the arachnoid and pia mater and is most commonly caused by rupture of an intracranial aneurysm if it occurs spontaneously. SAH typically presents with sudden, severe headache, often accompanied by nausea, vomiting, and neck stiffness. We report a rare case of non-aneurysmal SAH (NASAH) in an 83-year-old woman presenting with isolated acute neck pain and worsening chronic back pain, without headache or neurological deficits. Laboratory evaluation revealed hemorrhagic cerebrospinal fluid. Head and neck MRI revealed degenerative cervical spine changes and localized subarachnoid hemorrhage in the premedullary and cerebellomedullary cisterns, with no aneurysm or vascular abnormality detected on magnetic resonance angiography (MRA) and digital subtraction angiography (DSA). The patient was managed conservatively with neurological and hemodynamic monitoring, blood pressure control, analgesia, and supportive care. Follow-up imaging showed partial resolution of the hemorrhage, and she remained neurologically intact. This case highlights the importance of considering SAH in atypical presentations to ensure timely diagnosis and management.