距骨離断性骨軟骨炎と共存した足関節限局型色素性絨毛結節性滑膜炎の一例

抄録

A case of osteochondritis dissecans (OCD) accompanied by localized pigmented villonodular synovitis (LPVS) in the ankle joint is reported.
At first, this fifteen-year-old girl with a locking-type complaint was diagnosed as suffering OCD, and LPVS was overlooked, because a synovial nodule could not be seen by X-ray films and CT, and was too small to be found by arthroscopy and MRI. At the operation we found no osteochondral fragment, but a small synovial mass (LPVS) which impinged into the tibiotalar joint. This patient's symptoms disap-peared after removal of the LPVS lesion.
PVS commonly occurs in the knee and the hip joint, while only about five percent of these lesions are reported as involving the ankle. Although LPVS and diffuse-type PVS have identical pathology, the clinical manifestations of these subtypes are quite different. From a therapeutic standpoint, LPVS is non-aggressive and can be treated by simple excision, but diagnosis of this lesion is sometimes not easy.
Although early use of MRI and arthroscopy are useful to diagnose many joint diseases, surgeons should keep in mind the presence of an“overlap-lesion”like this case.