Dysosteosclerosis (DSS), also known as autosomal recessive dysosteosclerosis or X-linked recessive dysosteosclerosis, is a rare osteoclast-poor form of osteosclerosis that is presented during infancy and early childhood, characterized by progressive osteosclerosis and platyspondyly. Platyspondyly and other skeletal abnormalities are radiographic features of the disease which distinguish DSS from other osteosclerotic disorders. [Source: Wikipedia ]