Cervical myelopathy due to rheumatoid arthritis - Case report and review of the literature

We present the case report of a 62 year-old female suffering from destructi ve rheumatoid arthritis (RA)for more than 20 years. She had complaints of p rogressive gait impairment and numbness in hands and feet. Neurological exa mination showed an unstable gait and pyramidal tract signs. Anterior atlant oaxial subluxation with pannus formation and cervical myelopathy, were demo nstrated using conventional X-ray studies and MRT. She was conservatively t reated with a soft collar. Treatment with methotrexate and an intensive gai t revalidation program were started. RA commonly involves the cervical spin e, usually in advanced systemic disease after a mean delay of 16 years. Sub luxations of the cervical spine are found in 43 to 86% 50% of these patient s are asymptomatic. The reported rate of neurological impairment due to cer vical instability ranges from 7 to 58%. The three most common lesions resul ting from cervical RA are atlantoaxial subluxation (50 to 70%), subaxial su bluxation (15 to 25%) and cranial settling (20%). It is important to differ entiate between cranial settling and atlantoaxial instability, as the latte r may have a more benign history with less than 20% showing progressive ins tability. Cranial settling progresses in 35 to 50% of patients. The commone st presenting features of rheumatoid cervical myelopathy are isolated senso ry symptoms. Most patients were found to have multiple neurological deficit s once the myelopathy was diagnosed. A mean delay of 31 weeks between the f irst symptom and the diagnosis of the myelopathy is reported. The sensory s ymptoms are often misinterpreted as being die to entrapment neuropathy or r heumatoid peripheral neuropathy. Radiographic analysis indicates that the p osterior atlantoodontoid interval (less than or equal to 14 mm) is an impor tant parameter that shows excellent correlation with the severity of paraly sis.