Hi, this is Sagar Wagle, one of the musculoskeletal radiology fellows at Stanford University. We have a 19 year old male with history of ACL reconstruction and recurrent knee joint effusion. Aspiration of the effusion showed calcium pyrophosphate crystals. This button is related to ACL reconstruction. In CPPD arthritis, classically we see chondrocalcinosis which we do not see in this case. This patient also has a large knee joint effusion. The ACL graft that we see here, we do not see any high grade tear of the graft. We also see tear of the lateral meniscus. The medial meniscus is severely attenuated and this is consistent with either prior surgery or a meniscal tear. Here we see large knee joint effusion and this ultrasound image also shows the knee joint effusion. This is distal femur, these are just fat and this anechoic structure is the joint effusion. Calcium pyrophosphate deposition disease also called CPPD or pseudogout, the classic imaging finding in this is chondrocalcinosis. On the right, we see chondrocalcinosis right here and here. Usually this disease affects the elderly population and this can have acute exasperation which can mimic gout. Another important area that CPPD affect is the wrist. Here we have two different patients. Chondrocalcinosis in the wrist classically happens in triangular fibrocartilage complex also called TFCC. Here we do see chondrocalcinosis of TFCC. TFCC is located just distal to the ulna. Whenever you see chondrocalcinosis in the wrist and radiocarpal arthritis always suspect CPPD. On the left, we do see an example of radiocarpal arthritis. On the image in the right, we also see other areas of chondrocalcinosis. That's all for CPPD. Thank you for watching the video.

3rd Edition, CASE 48

3rd Edition

Rheumatology

CPPD

ACL reconstruction

chondrocalcinosis

pseudogout

meniscus tear