AAS is important extra-articular manifestation of RA, and should be detected before general anaesthesia and in situations at risk for a neck injury. 

A. Kuchi1, S. M. Perchinkova2

PHO City Health Centre Skopje1, University Clinic of Rheumatology Skopje, R. Macedonia2 

Atlantoaxial subluxation (AAS) is important and potentially life threatening complication of Rheumatoid arthritis (RA). It is defined when the space between odontoid process from C2 and arch of the atlas exceeds more than 3 mm. Aim of the study was to determine the frequency and the characteristics of atlantoaxial instability among our patients with RA and its dependence on the nature of the disease. 

92 outpatients from University Rheumatology Clinic in Skopje, with classical RA (ACR criteria 1988) were examined for the AAS. In all cases were analysed the duration of the disease, haematological and serological tests, disease activity (DAS 28), visual analogue scale (VAS) for the degree of articular pain  and verbal rating scale (VRS).for cervical-occipital pain. All patients underwent native and functional x-ray, CT scan and MRI of cervical spine. A complete neurological examination was obtained, with SEP of the n. medianus et n. tibialis.  

Atlantoaxial instability, with expressed cervical-occipital symptomatology, occurred in 54 from 92 (58,69% ) patients with RA. AAS appeared significantly more often in patients with longer duration of the disease (p<0,0001), in cases with significant cervical-occipital pain (VRS p<0,0001), with stronger joint pains (VAS), with higher values of SR (p=0,002), CRP (p=0,023), RF(p=0,000005), anti CCP (p=0,00003), and DAS 28 (p<0,0001). Anaemia and thrombocytosis (p=0,0008) appeared significantly more in cases with AAS.  Anterior AAS, (mostly combined with other types) was the most frequent type, presented in 41 participants (75,92%). In one case posterior AAS was detected, what is very rare finding. Positive SEP was significantly higher in the group with AAS.

Instability in atlantoaxial joint may result with numerous neurological symptoms, compression of the medulla spinalis and ultimately quadriparesis or quadriplegia. In patients with long-lasting active RA, persistent synovitis and inflammation of the transversal ligament on atlantoaxial joint may result with AAS and cause significant neurological problems. The presence of cervical subluxation presents a general anesthetic risk and risk for a neck injury. 

Routine cervical radiographs with the head in flexed position are recommended before surgical operations of the patients with RA.  
AAS is important extra-articular manifestation of RA, and should be detected before general anaesthesia and in situations at risk for a neck injury.