A woman with neck pain and hemiplegia.

PATIENT PRESENTATION

A 43‐year‐old woman presented with acute posterior neck pain, restricted neck motion, and right hemiplegia, which started 6 hours prior. Her vital signs were stable. Physical examination revealed restricted neck rotational motion, mild weakness in right‐sided extremities, and hypoesthesia at the C5 dermatome. The cranial nerve examination was normal. Laboratory findings indicated an elevated level of white blood cells. Head computed tomography and magnetic resonance imaging demonstrated no signs of stroke, stenosis, or dissection of the vessels. Subsequently, cervical computed tomography showed periodontoid calcium deposition around the dens of axis and protrusion to the posterior side (Figure 1).

FIGURE 1

Cervical computed tomography imaging showing the calcifications (arrows) around the dens of axis and protrusion to the posterior side. (A) Coronal view, (B) Sagittal view

DIAGNOSIS

Crowned dens syndrome (CDS). The patient started using a non‐steroidal anti‐inflammatory agent and methylprednisolone (30 mg). The symptoms of neck pain, restricted neck motion, and neurological defects subsided 5 days post diagnosis.

CDS, also known as periodontoid calcium pyrophosphate dihydrate crystal deposition disease, is mostly seen in elderly patients, characterized by severe acute neck pain, restricted neck rotational motion, shoulder girdle stiffness, and fever. CDS with neurological symptoms is rare, and only 1 CDS case with hemiplegia has been reported. Our case is noteworthy because the patient was young and had neurologic symptoms, which are atypical of CDS features. Initially, we suspected vertebral artery dissection, a common cause of stroke in children, young adults, and trauma patients, although cervical motion limitation is rarely seen. Physicians should be aware that the key physical symptom specific to CDS is restricted neck motion and that CDS can even cause neurologic symptoms.