Headache and neck pain are extremely common chief complaints in the emergency department. One study found that “symptoms involving head and neck” was the sixth-most common ED diagnosis, seen in 2.2% of ED visits.1 The estimated 1-year incidence of neck pain alone can be more than 20%.2 The majority of patients with headache and neck pain do not have a life-threatening problem. The challenge for emergency physician is to recognize signs of cervical artery dissection in patients presenting with head and neck pain. Early identification and treatment of dissection reduces the risk of stroke and death.
While the overall incidence of cervical artery dissection is very low, it is a common etiology of stroke in adults younger than 50, causing up to 10% of the cases.3 Incidence has increased in the past decade, likely due to improved imaging modalities. The incidence of spontaneous cervical arterial dissection is 3-5 per 100,000.4 The incidence of traumatic cervical artery dissection is 1 per 1000.4 Cervical arterial dissections most commonly occur in the carotid arteries, followed by the vertebral arteries.
Dissection is caused by an intimal tear leading to bleeding into the vascular wall, which can lead to vessel occlusion, thrombus with subsequent distal emboli, aneurysm formation, and subarachnoid hemorrhage. Arteries are most prone to dissection when they are stretched over bony prominences. Carotid artery dissection most commonly occurs 2 cm above the bifurcation of the common carotid artery, where the extra-cranial portion of the internal carotid artery travels over C2-3. Vertebral artery dissection most commonly occurs at C1-2, due to compression of the vessel against the C2 cervical foramina during head rotation, and at C5-6, where the artery enters the transverse foramina.4 Compression of the vessel can cause blood to pool and clot in the vessel, then subsequently embolize to distal vessels, resulting in ischemic stroke.
Early presentation of cervical artery dissection can be very subtle and overlaps with more common causes of headache and neck pain like tension headache or musculoskeletal neck pain. Up to 80% of cervical artery dissections are preceded by trauma to the head or neck.3 Dissection has been associated with chiropractic manipulation, weight lifting, roller coasters, and wrestling.4,5