Recently we studied a case of cysts of the internal semilunar car tilage, which we believe contributes to the knowledge of the etiology and pathogenesis of this condition. Twenty-two cases of cysts of the semilunar cartilage have been reported since Ebner1 described the first in 1904. Our case is the third reported case of cysts of the internal meniscus, the other two having been reported by Fisher2 and by Allison and O'Connor.3
In the twenty-two cases, the patients' ages varied from 16 to 55, but most of them were in the third decade. Twenty patients were men, and three were women. There was a history of trauma immediately preceding the appearance of the cyst in nine cases, including ours; there was no history of trauma in five cases; in nine cases the presence or absence of trauma as a possible inciting factor was not mentioned.