Clinics in diagnostic imaging (129). Posterior cruciate ligament ganglion cyst.

Ganglion cysts arising from the posterior cruciate ligament (PCL) of the knee are rare. We describe a 21-year-old Chinese woman who presented with right knee pain following a twisting injury six months prior. Her pain was exacerbated by squatting, although her range of knee motion was full. Magnetic resonance imaging showed a lobulated, well-defined, T1-hypointense and T2-hyperintense, septated cystic mass arising from the posterior aspect of the PCL. The diagnosis of a PCL ganglion cyst was confirmed by computed tomography-guided aspiration of the cyst. Due to persistent mild knee pain, the patient eventually underwent arthroscopic decompression of the ganglion cyst. The clinical features, diagnosis and management of PCL ganglion cysts are discussed.