myositis ossificans /əsif″əkanz/ , a rare inherited disease in which muscle tissue is replaced by bone. It begins in childhood, with stiffness in the neck and back, and progresses to rigidity of the spine, trunk, and limbs. The administration of diphosphonates may prevent the abnormal deposition of bone, but there is no cure after it has occurred. Metabolism of calcium and phosphate remains normal throughout the course of the disease. Compare myositis.
