A Rare Case of Parkinson's Disease with Severe Neck Pain Owing to Crowned Dens Syndrome

BACKGROUND Pain is regarded as one of the most common nonmotor symptoms in Parkinson's disease (PD). In particular, musculoskeletal pain has been reported as the most common type of PD-associated pain. Crowned dens syndrome (CDS), related to microcrystalline deposition in the periodontoid process, is the main cause of acute or chronic cervical pain. CASE PRESENTATION This report describes the case of an 87-year-old woman who had severe bradykinesia, muscle rigidity, gait disturbance and neck pain. Laboratory examination revealed marked elevations of white blood cells (10,100/µl) and C-reactive protein (CRP; 8.63 mg/dl). She was primarily diagnosed with severe and untreated PD, corresponding to Hoehn and Yahr scale score IV, with musculoskeletal pain and urinary tract infection. The patient was treated with antiparkinsonism drugs, antibiotic agents and nonsteroidal anti-inflammatory drugs, but they had only limited effects. Cervical plain computed tomography (CT) scanning detected remarkable crown-like calcification surrounding the odontoid process. Based on CT findings, the patient was diagnosed as having CDS with PD, and was immediately treated with corticosteroid. The severe neck rigidity with pain and the serum CRP level (0.83 mg/dl) of the patient were drastically improved within a week by the additional corticosteroid therapy. CONCLUSION Severe neck rigidity and bradykinesia in this patient might have strengthened the chondrocalcinosis around the odontoid process. Cervical plain CT scan is necessary and useful for the definitive diagnosis of CDS. CDS should be considered as a differential diagnosis of a possible etiology for musculoskeletal pain related to rigidity and bradykinesia in PD.