Ebner,1 in 1904, was the first to describe cyst formation in the external semilunar cartilage. Since then there have been twelve other cases reported: one by Schmidt,2 six by Riedel,3 one by Eden,4 and four by Ollerenshaw.5 The two cases reported here are apparently the first to be reported from this country.
REPORT OF CASES
—C. B., a man, aged 22, who entered the Presbyterian Hospital, Aug. 24, 1920, had had stiffness and pains in the right knee during the preceding three years. They were slight at first, and worse during the winter months. There had been times during the summer months when the knee was practically normal. There had been several acute exacerbations lasting for two or three weeks, during which time both limitation of motion and pain had been considerable. The pain had been most marked over the lateral surface