To investigate by magnetic resonance (MR) imaging the occurence of cervical spine (CS) involvement in rheumatoid arthritis (RA) patients.
Thirty consecutive unselected patients, who fulfilled the revised American College of rheumatology criteria for RA, were investigated. All patients had a complete physical and laboratory evaluation. Radiological evaluation included hand and wrist x-rays, as well as CS radiographs in anteroposterior, lateral and lateral in full flexion views. In addition, MR (Spin Echo T2-weighted saggital scans, palin and contrast enhanced T1-weighted sagittal and axial scans) was performed in all patients. Hand x-rays were evaluated according to the Sharp score. Disease activity was assessed by disease activity score for 28 joint indices (DAS-28).
There were 25 females and 5 males with a mean age of 46.6 years (23-67) and mean disease duration 9 years (1-22). Twenty three patients (76.6%) had positive IgM rheumatoid factor (RF). Five patients presented clinical findings, mainly cervical pain and stiffness of CS (four with positive and one with negative MR), while radiological findings of CS involvement were found in seven patients (23%). Five patients (16.6%) presented MR findings of CS involvement (anterior atlantoaxial subluxation 100%; vertical subluxation 20%; peridental pannus 80%; dens erosion 40%; brainstem compression 20%). Atlantoaxial subluxation correlated with high DAS-28, high level of swellen joint, high level of C-reactive protein and advanced erosive changes of the wrist and hand (high level of Sharp score) in the univariate analysis.
We conclude that the frequency of CS involvement in RA patients is high. In pateints with active erosive peripheral disease it is very probable to also have some changes in CS. These may be clinically important and in such cases, MR offer valuable information.