Bianchi S, Abdelwahab I F, Zwass A, Rettagliata F, Federici E, Ricci G
Department of Radiology, O.E. Ospedali Galliera, Genoa, Italy.
Can Assoc Radiol J. 1995 Aug;46(4):308-10.
A 53-year-old man known to have osteoarthritis of the left knee was examined because of a soft-tissue swelling overlying the pes anserinus tendon. Plain radiography and computed tomography revealed an expansile subchondral cyst of the proximal tibia. The cyst was multiloculated, had a sclerotic margin and an extraosseous soft-tissue component, and interrupted the cortex. Proof of a degenerative cyst was obtained by open biopsy. Such presentation in the knee is rare. Awareness of the possible aggressive behaviour of such degenerative cysts should help avoid confusion with neoplasm.
一名53岁的男性，已知患有左膝骨关节炎，因鹅足肌腱上方的软组织肿胀而接受检查。X线平片和计算机断层扫描显示胫骨近端有一个膨胀性的软骨下囊肿。该囊肿为多房性，有硬化边缘和骨外软组织成分，且中断了皮质。通过开放活检证实为退行性囊肿。这种在膝关节的表现很罕见。认识到这种退行性囊肿可能具有的侵袭性表现，有助于避免与肿瘤混淆。
