抄録
Recently, many knee joint ganglia have been diagnosed by MRI. However, there are no reports of the natural course of knee joint ganglia. We encountered two cases in which the knee joint ganglion shrank or disappeared.
Case 1. A two-year-old boy was brought to our clinic with a complaint of bilateral knee snapping. Left knee snapping disappeared at the age of three. MRI was performed on the right knee at the age of four. There were normal menisci, with a ganglion between the tibia and popliteal muscle. Right knee snapping was gone at the age of five, and follow-up MRI demonstrated shrinking of the ganglion.
Case 2. A twenty-nine-year old woman consulted our clinic with a complaint of right knee pain and maximal-flexion disturbance. MRI was performed three months after the first consultation. There were normal menisci, and a ganglion around the posterior cruciate ligament. She was scheduled for arthroscopic examinations. However, her complaint disappeared one month after MRI examination. Follow-up MRI demonstrated disappearance of the ganglion.
Many kinds of therapy have been reported for knee joint ganglia. Some reports proposed total ganglion resection by arthrotomy, but there was a report of recurrent knee joint ganglion after arthroscopic treatment. Although we describe two cases of spontaneously disappearing or shrinking knee joint ganglia, the rate of disappearance of each knee joint ganglion is unknown. We propose avoiding arthrotomy and observing the ganglion for a few months in patients without severe complaint caused by the knee joint ganglion.
