| dc.description.abstract | Objective - To describe and compare computed tomographic (CT), arthroscopic and histopathologic findings of elbow joints of dogs suffering from coronoid dysplasia (CD) and to assess dysplastic bone and cartilage histopathologically after arthroscopic subtotal coronoidectomy.
Study design - Prospective study.
Sample population – Forty-five osteochondral samples of 38 client-owned dogs that underwent arthroscopic subtotal coronoidectomy to treat unilateral or bilateral CD.
Material and Methods - Computed tomographic studies were evaluated by a certified radiologist (Prof. dr. G. Voorhout) and a board certified veterinary orthopaedic surgeon (Dr. L.F.H. Theyse PhD, DVM, ECVS). Arthroscopic findings were evaluated and during arthroscopic intervention dysplastic bone and cartilage were collected for histopathologic assessment by the same orthopaedic surgeon. Computed tomographic scans were reviewed for coronoid pathology including, (i) displaced fragments, (ii) non-displaced fragments, (iii) dysplastic coronoid (abnormal contour and structure (lucency), and the presence of osteophytes). The arthroscopic recordings were reviewed for (i) displaced fragments of subchondral bone, (ii) non-displaced fragments of subchondral bone (fragment in the radio ulnar joint, between the radius and ulna), and (iii) osteochrondromalacia. Slices of formalin-fixed, paraffin-embedded arthroscopic bone and cartilage samples were stained with haematoxylin and eosin (HE) and reviewed by the author and a board-certified veterinary pathologist (Prof. Dr. A. Gröne DVM, ECVP, ACVP).
Results – The most common CT findings were coronoid dysplasia and fragmentation of the medial coronoid process (MCP). Displaced fragments appeared more than non-displaced fragments. Mean age at arthroscopy was 25 months. The most common arthroscopic finding were fragmentation of the subchondral bone of the MCP (average displaced fragments than non-displaced fragments) in combination with osteochondromalacia, comparable with the CT findings. Histopathological findings showed most of the time more or less normal articular cartilage, and some microscopic slides showed chondrons (chondrocytes together forming isogenic groups) and necrosis. Necrosis of the subchondral bone was the most common histopathological finding; it appeared in almost all microscopic slides. Most blood vessels also showed necrosis.
Conclusion – The results recognized in dogs suffering from CD demonstrated a wide range of CT, arthroscopic and histological findings. Histological findings primarily showed necrosis of the subchondral bone. This is most likely caused by a disturbance of vascularisation.
Clinical Relevance – Histological slides provide valuable information with respect to the dysplastic bone and cartilage, concluding CD is primary located in the osteochondral bone and not in the articular cartilage. This gives better understanding of the pathogenesis of CD. | |
