Definition.—Either a local or general myositis, in which a progressive ossification takes place in the affected muscles.
Etiology.—Like acute myositis, the cause is unknown, though young men are more frequently affected than women.
Pathology.—The early changes that occur are the same as those of acute myositis, the later changes being those of calcification, which render the muscles and joints stiff and immobile. The process in rare cases extends to the heart.
Symptoms.—The additional symptoms to acute myositis are immobility of the muscles and joints.
Diagnosis.—This is made by the hard, stiff condition of the muscles, and finally by ankylosis of the joints.
Treatment.—The treatment has been unsatisfactory, and can be only palliative.
The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.