JESUS SÁNCHEZ 1 , JOSÉ M. GONZALO-ORDEN 1 , MÁRIO M. D. GINJA 2 , PAULA A. OLIVEIRA 3 , LUIS E. REYES 1 , ALICIA E. SERANTES 1 , MARIA A. ORDEN 1 1 Department of Animal Pathology, Animal Medicine, University of León, 24071 León, Spain , 2 Department of Veterinary Science-CITAB and 3 Department of CECAV, University of Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal. Veterinary Radiology & Ultrasound March/April 2010 51 2 159 - 161 An Andalusian Stallion with left hind limb lameness had a radiolucent lesion in the medullary cavity of distal tibial metaphysis. After euthanasia for other disease, the tibia was examined with magnetic resonance (MR). The MR imaging sequences were characterized by a double line sign, although showing quite different lesion area intensities. Histologically, the lesion was compatible with medullary infarction being characterized by normal spongy bone, areas of abundant fibrous tissue and numerous necrotic adipocytes in various stages of destruction.