Chondrocalcinosis is a radiographic diagnosis that refers specifically to the presence of calcium -containing crystals detected as radiodensities in cartilage. Hyaline cartilage involvement is visible as a thin, linear calcification separated from but parallel to the articular cortex. It is found most commonly at the wrist, knee, elbow, hip, and shoulder. Fibrocartilage involvement is seen as thick, irregular calcifications with poorly defined margins. It is found most commonly in the knee menisci, lunato-triquetral ligament, triangular fibrocartilage of the wrist, symphysis pubis, and annulus fibrosis. Chondrocalcinosis is most commonly associated with dalcium pyrophophate dihydrate (CPPD) crystal deposition, but may be associated with a number of other diseases and is not always symptomatic. Chondrocalcinosis is also seen in hyperpara-thyroidism, hemochromatosis, ochronosis, Wilson’s disease, and occasionally with gout and degenerative arthritis. The incidence of chondrocalcinosis associated with CPPD at the wrist, knee, and symphysis approaches 100%, allowing for a screening procedure of suspected individuals by performing collimated spot radiographs of those articulations. Nevertheless, presence of CPPD cannot be definitively diagnosed without clinically demonstrating the presence of crystals in the joint fluid. When symptoms are present, they most commonly manifest as gout-like attacks of inflammation referred to as “pseudogout.” The knee is the most commonly involved joint both radiographically and clinically. Hyaline chondrocalcinosis is most visible on the femoral condyles and posterior surface of the patella. Meniscal fibrocartilage chondrocalcinosis is seen on the AP projection as triangular calcifications with the apices directed toward the intercondylar notch from the medial and lateral compartment.

The current patient has a classic presentation of chondrocalcinosis. He has no history of or symptoms suggestive of systemic disease. His complaint of sudden pain and swelling in a single joint that responded well to an oral NSAID, accompanied by the noted radiographic findings strongly suggests a clinical diagnosis of CPPD. However, the emergency room staff elected not to do a joint aspiration to verify this diagnosis. Should the patient have a recurrence of his symptoms, aspiration of the affected joint would be recommended, as well as a laboratory work-up including a chemistry panel, parathormone, and iron panel to rule out systemic disease.