RESPIRATORY ABNORMALITIES DUE TO CRANIOVERTEBRAL JUNCTION COMPRESSIONIN RHEUMATOID DISEASE

Objectives-To assess the extent and severity of respiratory insufficie ncy severe rheumatoid atlantoaxial dislocation and its relation to com pression of the neuraxis. Methods-Twelve patients with severe atlantoa xial dislocation due to rheumatoid disease were studied. Detailed clin ical, CT myelography and respiratory assessment including nocturnal ox imetry, were performed on all patients. Results-All patients were seve rely disabled by their underlying disease but none had symptoms of hyp oventilation. All the patients with C1 compression had myelopathic fea tures. Those with medullary deformation (moulding and/or stretch) had abnormal noctural oximetry whilst no significant desaturations were se en in the remaining patients. Postoperative studies showed resolution of noctural desaturations. Conclusion-This study suggests that clinica lly unsuspected respiratory insufficiency may be common in patients wi th severe medullary compression associated with rheumatoid atlantoaxia l dislocation. It emphasises the importance of careful respiratory mon itoring including nocturnal oxygen saturation in patients with major a tlantoaxial dislocation due to rheumatoid disease.