CHONDROMATOSIS WITHIN A MENISCAL CYST OF THE KNEE

A 32-year-old man complained of left gonalgia for 2 years and noticed a soft part tumor on the lateral side of his left knee. Roentgenograms showed some small calcified shadows at the same site of the tumor. Ar throscopy revealed a lateral meniscus to be an incomplete discoid with degenerative tears. At the operation, a multilocular soft part tumor was noticed in continuity with the lateral meniscus macroscopically. S mall, loose bodies and gelatinous fluid were found in the cavity of th e tumor. Histologically loose bodies were chondroma and the soft part tumor was meniscal cyst. The meniscal cyst wall contained hyaline cart ilagenous tissue. Therefore it was thought that chondroma originated f rom the cyst wall.