A 4.5-year-old intact male Labrador Retriever dog had a 1-month history of right forelimb lameness with painful swelling of the elbow. The radiographic findings of increased synovial mass with mineralized opacities and the gross and histologic findings in the synovial biopsy specimens were consistent with a diagnosis of primary (idiopathic) synovial osteochondromatosis. Twenty months after initial presentation, based on progression of clinical signs and radiographic evidence of marked bone lysis in the distal aspect of the humerus and proximal aspects of the radius and ulna, the affected leg was amputated. The histologic diagnosis was chondrosarcoma with fibroblastic differentiation and bone lysis. The chondrosarcoma was interpreted as malignant transformation of primary synovial osteochondromatosis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.