Neurophysiological study vs. magnetic resonance imaging in early diagnosis of rheumatoid cervical myelopathy

Abstract EN

Objective : the purpose of this study was to detect early signs of cervical myelopathy on the basis of neurophysiological and radiological findings in rheumatoid arthritis (RA) patients.

Methodology : the study was conducted on forty patients (37 females and 3 males) with definite rheumatoid arthritis 13 of whom (32.5 %) had atlantoaxial subluxation (AAS).

Their neurophysiological data were compared with 25 ages and sex matched normal volunteers.

Somatosensory and motor evoked potentials (SSEP & MEP) for both upper limbs were done for each subject.

Magnetic resonance imaging (MRI) of the cervical spine was performed in all patients.

Results : Twenty-three patients (57.5 %) had cervical pain.

Five (12.5 %) patients displayed clinical signs of cervical myelopathy; all of them had AAS.

Significant prolongation of central conduction time of both SSEP and MEP was found in patients with AAS as compared with those without.

Nine patients (22.5 %) had prolongation of CCT as detected with SSEP and ten patients (25 %) had prolongation of central motor conduction time (CMCT) as detected with MEP with higher percentage among patients with AAS.

Six patients (15 %) had affection of peripheral conduction time with or without affection of central conduction time.

Out of the 40 patients, 13 had AAS 38 % of them displayed signs of cord compression as detected with MRI.

However, 27 patients out of 40 (67.5 %) had periodontitis panes, 27 patients had odontoid erosion, eight patients (20 %) had evidence of degenerative disc changes with higher percentage of MRI abnormalities in patients with AAS as compared to patients without.

Conclusion : these results support that examination of central conduction time with SSEP and MEP are the most reliable data for evaluating the risk of neurological damage especially in patients with AAS.