Spectrum of arthroscopic findings in 84 canine elbow joints diagnosed with medial compartment erosion

Elbow dysplasia is an important cause of forelimb lameness in large breed dogs. The aim of this study was to report on the arthroscopic findings associated with medial compartment erosion (MCE) of the canine elbow joint. Retrospectively, records of 84 elbow joints from 66 dogs diagnosed arthroscopically with MCE were retrieved from a medical records database (2008 - 2012). The radiographic degree of osteoarthritis was determined. Arthroscopic images and videos were evaluated in detail. In nine joints (10.7%), MCE was the only pathological finding (= group 1). Group 2 (n = 50, 59.5%) consisted of elbows with MCE concomitant with medial coronoid process (MCP) pathology. In group 3 (n = 25 joints, 29.8%), MCE was diagnosed during a second-look arthroscopy in dogs presented with lameness after arthroscopic treatment for medial coronoid disease. There was a significant age difference (p < 0.001) between the groups, with dogs in group 1 being the oldest. Complete erosion of the medial compartment was most commonly found in group 1, whereas focal cartilage erosion was mostly identified in group 2. Overall, additional cartilage pathology of the lateral part of the humeral condyle and/or the radial head was recognized in 58.3% of the joints (49/84).