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Craniocervical junction involvement in rheumatoid arthritis: a clinical and radiological study.

OBJECTIVE
To make a comparative evaluation of different imaging techniques for studying the craniocervical junction involvement in patients with rheumatoid arthritis (RA). Upper cervical spine involvement was compared with clinical and immunological data.


METHODS
Patients (n = 47) underwent plain radiographs and computerized tomography (CT) and magnetic resonance (MR) study of the craniocervical junction. Neurological examination following clinical signs of possible atlantoaxial involvement was performed in all patients following the Ranawat classification.


RESULTS
Radiographic and MR images showed craniocervical involvement in 41.3% and 61% of the patients, respectively. Immunological data were not correlated with imaging findings, whereas Ranawat class II and III of neurological involvement seem to be predictive of atlantoaxial alteration.


CONCLUSION
Conventional radiography allowed us to detect 41.3% of patients with craniocervical involvement, but only in advanced stages of the disease. MR imaging had the unique potential of direct and detailed synovial visualization, especially in the gadolinium enhanced axial images, resulting in the early diagnosis of craniocervical RA.