Elbow dysplasia - OCD of the elbow

What is ... ?: 

 The term elbow dysplasia refers to several conditions that affect the elbow joint: osteochondrosis of the medial humeral condyle, fragmented medial coronoid process, ununited anconeal process, and incongruent elbow. More than one of these conditions may be present, and this disease often affects both front legs. An affected dog shows forelimb lameness and elbow pain. These conditions may actually be different manifestations of a single disease process, osteochondritis dissecans (OCD) . OCD is abnormal maturation of cartilage (the specialized connective tissue from which bone develops). While this in an inherited defect, environmental factors such as diet, activity, and trauma also have a role in the development and progression of the disease.

Osteochondritis dissecans (OCD): A fragment of cartilage peels away from the bone, within the joint.
Osteochondrosis of medial humeral condyle:  OCD develops on the elbow end of the humerus (the long bone in the front leg above the elbow).
Fragmented medial coronoid process and ununited anconeal process: The coronoid and anconeal processes are small bones which fuse with the main part of the ulna as the animal matures. (The ulna and the radius are the two bones which make up the front leg between wrist and elbow). These terms describe the condition where those processes either break off from the ulna, or fail to fuse normally.
Incongruent elbow: The bones which form the elbow joint grow at different rates and do not fit together properly.

How is ... inherited?: 

This is a polygenic condition (more than one gene is necessary to cause the disease), although it is not currently known how many or which genes are responsible. Environmental factors such as over-feeding, which causes fast weight-gain and growth, can also affect the development of this condition in dogs that are genetically predisposed to it.

What does ... mean to your dog & you?: 

 Lameness usually starts insidiously at 7 to 10 months of age. It is present every day, and may be most obvious when you dog first gets up, or starts to walk or run. The prognosis (the likely outcome) depends on how far the disease has progressed when treatment begins. Good clinical results (ie. your dog will not be painful) are usually seen if treatment starts early, before osteoarthritis (degenerative changes in the joint) has developed. If left untreated, your dog’s pain and lameness will gradually get worse.

How is ... diagnosed?: 

 The initial lameness may be very subtle with this condition, and it may be some time before it can be documented or diagnosed. Your veterinarian will suspect elbow dysplasia if you have a young, fast-growing, large breed dog (especially those breeds listed above), with forelimb lameness and elbow pain. S/he will perform a physical exam and watch your dog walk or run to confirm which limb, and which joint, is painful. X-rays are necessary to diagnose elbow dysplasia. Your veterinarian will probably x-ray both elbows, because this disease is often present in both sides even if your dog is only lame on one side. If possible, s/he may do a CT scan; this technique will show certain bone fragments better than plain x-ray films.

How is ... treated?: 

 Surgery is usually recommended to remove a bone or cartilage fragment. If unequal bone growth is the problem, surgery may help to relieve the pressure at the joint.

Medical management recommendations include monitoring the diet (to avoid excess weight gain and fast growth), and controlling exercise. Medications such as non-steroidal anti-inflammatory drugs may help with pain relief. "Chondroprotective agents" such as glucosamine may also be prescribed.

Breeding advice: 

 Do not breed affected dogs, or dogs which produce offspring with elbow dysplasia. The Orthopedic Foundation of America (OFA - www.offa.org) maintains an elbow registry screening programme, as do European organizations. The Institute for Genetic Disease Control in Animals (GDC -www.vetmed.ucdavis.edu/gdc/gdc.html) provides evaluation of elbows as recommended by the International Elbow Working Group.



 Abstracts of the 7th Annual Meeting of the International Elbow Working Group. 1996. Veterinary Comparative Orthopaedics and Traumatology. 9(2):58-71.

Bennett D, May C. 1995. Joint diseases of dogs and cats. In EJ Ettinger and EC Feldman(eds). Textbook of Veterinary Internal Medicine, pp. 2032-2077.WB Saunders Co., Toronto.

 Schrader SC. 1995 Differential diagnosis of nontraumatic causes of lameness in young growing dogs In JD Bonagura (ed.) Kirk's Current Veterinary Therapy XII, pp. 1171-1180. WB Saunders Co., Toronto

What breeds are affected by ... ?