title: The role of osteonecrosis in canine coronoid dysplasia: arthroscopic and histopathological findings.
abstract: Coronoid dysplasia (CD) or medial coronoid disease is part of canine elbow dysplasia and eventually results in osteoarthrosis. Although CD was originally attributed to disturbed endochondral ossification, more recent data point to the subchondral bone. The objective of this study was to assess dysplastic bone and cartilage of dogs that underwent unilateral or bilateral arthroscopic subtotal coronoidectomy for the treatment of CD. Arthroscopic findings and histopathology of bone and cartilage removed from elbow joints with CD were compared. The most common arthroscopic finding was fragmentation with softening of the subchondral bone of the central part of the medial coronoid process. In dogs without obvious fragmentation, CD was characterised by bone softening and chondromalacia. During arthroscopic intervention dysplastic bone and cartilage were collected for histopathological assessment. Forty-five slices of formalin-fixed, paraffin-embedded bone and cartilage samples were stained using haematoxylin and eosin and evaluated. Histopathological findings primarily consisted of osteonecrosis of subchondral bone with necrosis within the marrow spaces. Histopathological changes in the articular cartilage were characterised by fibrillation, chondrocyte clone formation, and focal cartilage necrosis. The pathology was found primarily in the subchondral bone and not in the articular cartilage. Vascular compromise may play a role in the pathogenesis of osteonecrosis in CD.
authors.affiliation: Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM, Utrecht, The Netherlands.
authors.forename: I C
authors.initials: IC
authors.lastname: Mariee
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Gröne
authors.affiliation: Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM, Utrecht, The Netherlands. Electronic address: l.f.h.theyse@uu.nl.
authors.forename: L F H
authors.initials: LF
authors.lastname: Theyse
mesh_terms: D000818:Animals; D001182:Arthroscopy / Q000662:veterinary*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000473:pathology*; D004283:Dog Diseases / Q000209:etiology / Q000473:pathology*; D004285:Dogs; D005260:Female; D005552:Forelimb / Q000473:pathology; D007596:Joints / Q000473:pathology; D008297:Male; D010003:Osteoarthritis / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D010009:Osteochondrodysplasias / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D010020:Osteonecrosis / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D011446:Prospective Studies; D011859:Radiography
keywords: Arthroscopy; Canine elbow dysplasia; Coronoid dysplasia; Histopathology; Osteonecrosis