Intraligamentous Synovial Chondromatosis of the Anterior Cruciate Ligament: A Case Report.

Abstract

Synovial chondromatosis of the anterior cruciate ligament (ACL) is rare, with only a few cases having been reported1-3. In those reports, chondral bodies were situated around the cruciate ligaments. We present a case of synovial chondromatosis in the intraligamentous area of the ACL. To our knowledge, the case described here is the first reported case of intraligamentous synovial chondromatosis of the ACL. The patient was informed that data concerning the case would be submitted for publication, and he provided consent. A forty-seven-year-old man with no history of substantial trauma presented with progressive pain in the left knee and limited range of motion. He walked with a limp and had difficulty squatting and climbing up and down stairs. On examination, the knee was found to have mild effusion. Extension of the knee was limited to –15°, with terminal pain. The McMurray test was negative. Ligamentous injuries were not detected; the Lachman test, pivot-shift test, anterior and posterior drawer tests, and varus and valgus stress tests were all negative. The numeric rating scale score for assessment of pain intensity was 8 (range, 0 [best] to 10 [worst]), and the Lysholm knee scale score was 55 points (range, 0 [worst] to 100 [best]). Radiographs showed no abnormalities. Magnetic resonance imaging (MRI) revealed swelling of the ACL and an intraligamentous mass with low signal intensity on T1-weighted imaging and high signal intensity on T2-weighted imaging (Figs. 1-A and 1-B). …