A case of myositis ossificans in an army officer following a trauma received while riding led me to investigate the prevalence of this condition. I was interested in determining whether this condition, or the so-called riders' bone, is common in our cavalry.
Knowing his interest in bone tumors, I referred my patient to Dr. Bloodgood, who called my attention to the case of another army officer and most kindly gave me access to his large compilation of cases of bone tumors. After I had reviewed this large group of cases, had searched the literature, and sent a questionnaire to the surgeons of all our cavalry regiments, I came to the conclusion that these two cases were sufficiently unusual to be worth reporting.
REPORT OF CASES
—W., aged 40, a captain in the ordnance department, was some-what bowlegged, and both knees had been enlarged since childhood. He had ridden