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Elbow Dysplasia in Dogs

(Ununited Anconeal Process, Fragmented Medial Coronoid Process, Osteochondrosis of the Humeral Condyle)


Joseph Harari

, MS, DVM, DACVS, Veterinary Surgical Specialists, Spokane, WA

Reviewed/Revised Nov 2020 | Modified Oct 2022
Topic Resources

Ununited Anconeal Process in Elbow Dysplasia in Dogs

This results when there is separation of the ossification center of the anconeal process from the proximal ulnar metaphysis. Fusion should be completed by 5–6 months of age. The fracture is postulated to result from a biomechanical imbalance of force and movement in the rapidly growing elbow. Initially, the anconeal process is connected to the ulna by a bridge of fibrous tissue, which fragments to form a pseudoarthrosis, and the elbow becomes unstable. This joint laxity continues to damage the articular cartilage, and secondary osteoarthritis results. A hereditary basis has been implicated but not proved.

Lameness develops insidiously between 4 and 8 months of age; however, some bilateral cases may not be diagnosed until dogs are >1 year old. Affected elbows may deviate laterally, and the range of motion is restricted. Advanced cases have osteoarthritis, joint effusion, and crepitus. Clinical signs are suggestive, and the diagnosis is confirmed by radiography Radiography of Animals Radiography (generation of transmission planar images) is one of the most commonly used diagnostic tools in veterinary practice even though other imaging modalities such as ultrasonography,... read more Radiography of Animals . A lateral radiograph of the elbow in the flexed position allows visualization of the ununited process. Both elbows should be examined because the condition can be bilateral.

Fragmentation of the Medial Coronoid Process in Elbow Dysplasia in Dogs

Osteochondrosis of the Medial Humeral Condyle in Elbow Dysplasia in Dogs

This results from a disturbed endochondral fusion of the epiphysis of the medial epicondyle with the distal end of the humerus. The exact cause is unknown, but because the carpal and digital flexors originate from the ventral aspect of this structure, it may represent an epiphyseal avulsion. It results in pain on flexion of the elbow or deep digital palpation and is accompanied by soft-tissue swelling. Radiographically, radiodense structures have been seen caudal and distal to the area of the medial epicondyle.

Treatment of Elbow Dysplasia in Dogs

Early surgical treatment is recommended before degenerative joint disease Degenerative Arthritis in Dogs and Cats Degenerative joint disease, ventrodorsal projection, characterized by irregular bone margins in the joint. Degenerative joint disease, lateral projection, characterized by irregular bone margins... read more Degenerative Arthritis in Dogs and Cats develops. For fragmentation of the medial coronoid process, a medial arthrotomy or arthroscopy is performed and the fragmented process removed. For ununited anconeal process Ununited Anconeal Process Ununited anconeal process, characterized by separation or cleavage of the bone tip from the proximal ulna. Elbow dysplasia is a generalized incongruency of the elbow joint in young, large, rapidly... read more Ununited Anconeal Process , either a lateral arthrotomy is performed and the ununited process removed, or a midshaft ulnar osteotomy is performed to relieve asynchronous growth and result in union of the process. Reattachment of the process by screw fixation is also an option. For osteochondrosis Osteochondrosis in Dogs Osteochondrosis of the shoulder in a 5-month-old Irish Wolfhound, characterized by subchondral bone lucency and flattening of the caudal humeral head. Osteochondrosis of the stifle in a dog... read more Osteochondrosis in Dogs , the subchondral bone lesion is curetted to stimulate fibrocartilage formation. Transplantation of cartilage plugs in lieu of curettage has recently been described. Prognosis after surgery is good if degenerative joint disease has not developed in the joint. Aspirin or NSAIDs Nonsteroidal Anti-inflammatory Drugs in Animals The importance of pain management and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in animals has increased dramatically in recent decades, and use of NSAIDs in companion animals... read more Nonsteroidal Anti-inflammatory Drugs in Animals (eg, carprofen, deracoxib, firocoxib, meloxicam, tepoxalin) can be used to reduce pain and inflammation Pathophysiology of Inflammation in Animals The initial inflammation phase consists of three subphases: acute, subacute, and chronic (or proliferative). The acute phase typically lasts 1–3 days and is characterized by the five classic... read more . Joint-fluid modifiers (glycosaminoglycans, hyaluronic aid) and acupuncture may be useful, although most reports are anecdotal. Joint injection with mesenchymal cells or platelet-rich plasma has also been described; reports are inconclusive.

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