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a chronic form of spondylitis primarily in males and marked by impaired mobility of the spine; sometimes leads to ankylosis

a chronic form of spondylitis primarily in males and marked by impaired mobility of the spine; sometimes leads to ankylosis

The form of rheumatoid arthritis affecting the spine. It occurs predominantly in young males and produces pain and stiffness as a result of inflammation of the sacroiliac, intervertebral, and costovertebral joints. Etiology is unknown.