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.