Ganglion cysts associated with cruciate ligaments of the knee: a possible cause of recurrent knee pain.

Intraarticular ganglia of the knee are uncommon; however, these ganglion cysts may produce knee discomfort without a clear etiology. We present the cases of 10 patients with ganglion cysts arising from cruciate ligaments of the knee joint who underwent arthroscopic excision after MR examination. The MR findings, clinical features and arthroscopic findings were evaluated comparatively. Diagnoses were confirmed by means of a histological study after arthroscopic excision. The cysts were fluid-filled, with low T1-weighted signal intensity and high T2-weighted signal intensity. Except for two patients with recent accidents, the remaining eight presented chronic pain without any history of trauma. Pain was the most frequent clinical sign. It was associated with knee extension in 3 cases and with flexion in 3 cases. In 7 cases, cysts were exclusively associated with the anterior cruciate ligament (ACL). Only in one case was a cyst associated with an ACL rupture. Four patients presented meniscal lesions. All ganglia appeared solitary in each knee. Postarthroscopy evolution was painless in 8 patients. Histologic diagnoses corresponded to ganglion cysts. The tissues from the patient with the ACL rupture presented a fibrous reaction with myxoid degeneration forming intraligamentary ganglion cysts.