A seven-year old male, neutered Great Dane presented with a five-week history of left thoracic limb lameness.
Examination revealed a firm, fixed, non-painful swelling medial to the left olecranon and resentment of flexion of the elbow. Radiology (fig. 1) revealed irregular loss of bone within the olecranon. Thoracic films were unremarkable. STIR-weighted MR-scans of the elbow revealed a focal area of bone inflammation consistent with neoplasia (figs. 2 & 3).
Impression smears from needle aspirates of the swelling were consistent with osteosarcoma, and the owner elected not to pursue further treatment.
This case illustrates the exception to the rule that such tumours usually occur ‘near to the stifle’ (distal femoral/ proximal tibial epiphyses) and ‘away from the elbow’ (proximal humeral/ distal radial epiphyses). It also illustrates the graphic appearance of metabolic bone changes on MR imaging.