Thoracic intervertebral discitis in rheumatoid arthritis due to costovertebral joint involvement.

Discitis (with intervertebral disc destruction), found pathologically in the thoracic region of 8 out of 114 rheumatoid patients, is shown to derive and spread from primary rheumatoid involvement of the costovertebral joints. Erosion and destruction of bone may occur, followed by healing, visible radiologically as disc narrowing and posterolateral bony sclerosis and sometimes with ankylosis. There are few clinical symptoms, since most of these patients have limited locomotor function.