Intra-articular ganglion cysts of the knee.

A ganglion is a cystic mass with myxoid matrix that occasionally occurs within muscles, tendons, and menisci. A ganglion cyst within the knee is very rare, with few reports to be found. We are reporting eight cases of a ganglion within the knee joint. Our cases include two ganglia in the infrapatellar fat pad which have not been previously reported. Ganglion cysts do not have specific symptoms. We hypothesize that symptoms of a ganglion cyst may correlate with the size and the location within the knee joint. The diagnosis of ganglia within the knee was established by magnetic resonance imaging study and confirmed by pathological testing. All the patients were treated successfully using the arthroscopic technique.