[The severity of rheumatoid arthritis as a timely predictor of instability in the asymptomatic cervical spine]

Cervical spine involvement is common in patients with RA, risk factors such as disease activity may be related to asymptomatic cervical instability.

To determine the associated factors for asymptomatic cervical spine instability in patients with rheumatoid arthritis.

Case and control study from the external spine and rheumatology consultation of a level II trauma center to identify all patients diagnosed with rheumatoid arthritis (RA) and asymptomatic cervical instability. With simple X-rays of the cervical spine, carrying out radiographic measurements, the diagnosis of cervical instability was performed, risk factors such as the presence of rheumatoid factor (FR), previous articular surgeries, elevations of the C-reactive protein (PCR) values were evaluated. The severity and activity of the disease measured in the activity index of 28 articulations (DAS 28) in addition to the index of activity of the simplified disease (SDAI).

We assessed 32 patients, nine patients (28.1%) met the criteria for instability of the anterior cervical spine atlantoaxial subluxation (SAAa) (100%), also one patient with SAAa presented vertical subluxation (SV), risk factors more relevant: DAS 28 with an OR = 3.54, SDA with an OR = 2.34 and finally the PCR 1.0 its OR = 2.88.

The risk factors associated opportunely in our population are the severity of the activity of the disease that we can see in the DAS and SDAI when applied in patients and PCR 1.0.