Clinical history An 8 year Borzoi male was lame on the left hind limb. It was presented for an anticipated TTA surgery. Radiographs were made of the left stifle. Radiographic diagnosis A destructive lesion is in the proximal tibia with only minimal periosteal new bone medially. The lesion is probably a malignant tumor. They are often synovial cell sarcomas or malignant histiocytosis. No radiographic changes were seen to support the clinically suspected cruciate ligament injury or secondary arthrosis. The destructive changes are easier seen (arrows) when compared with the normal study on the right. Comments We have seen earlier studies of potential cruciate ligament disease that actually had a malignant lesion affecting the stifle joint that was causing the clinical signs. The other frequent syndrome was that of chronic secondary arthrosis associated with hip dysplasia that was thought the cause of the clinical signs when an additional malignant tumor was found at the stifle.
