Objective: To compare radiographic elbow arthrosis with arthroscopic cartilagepathology in Labrador retrievers with elbow osteoarthritis secondary to medialcoronoid process (MCP) disease. Study Design: Retrospective epidemiological study. Animals: Labrador retrievers (n ¼ 317; 592 elbow joints). Methods: Data were collected retrospectively (June 2007–June 2011) to identifyLabrador retrievers with thoracic limb lameness and elbow pain, a complete set ofelbow radiographs, and a comprehensive arthroscopic surgery report. Each radiographwas scored for osteophytosis on the anconeal process and ulnar subtrochlear sclerosisusing a modification of the International Elbow Working Group (IEWG) scoringsystem. Elbows affected by traumatic MCP fracture, humeral condylar osteochondrosis, or ununited anconeal process were excluded. The arthroscopic report was used togenerate a composite cartilage score (CCS; 0 ¼ normal, 1 ¼ mild, 2 ¼ moderate,3 ¼ severe) for each elbow joint. Ordinal regression analysis was performed to test therelationship between radiographic arthrosis score and CCS. Results: There was a significant relationship between radiographic elbow arthrosisand CCS (P <.001). Elbows with a higher radiographic score were significantly morelikely to have a higher CCS than elbows with a lower radiographic score. For everymonth increase in age, the odds of having a higher CCS increased by 0.016 (1.6%). Conclusions: Radiographic arthrosis can be used to predict the severity ofarthroscopic cartilage pathology in Labrador retrievers affected by MCP disease.