Elbow Dysplasia

Elbow dysplasia is the most common cause of forelimb lameness in large breed dogs. The term refers to the abnormal development of the 3 bones which make up the elbow joint, causing abnormal wear of the articular cartilage, and formation of fragments of bone or cartilage within the joint. The condition occurs in young, rapidly growing dogs, with most patients being diagnosed under 2 years of age, with a second group of patients being diagnosed later in life. The most common underlying cause of elbow pain is a small fragment of bone called the medial coronoid process which displaces and constantly irritates the elbow joint. The abnormal wear of cartilage and formation of fragments within the joint lead to the progression of debilitating osteoarthritis and ongoing joint pain. There is a progression of medial compartment syndrome, where the articular cartilage is lost from the inside aspect of the elbow, and bone rubs against bone.

The diagnosis of elbow dysplasia and fragmented medial coronoid process is based on clinical examination and early osteoarthritic changes seen on x-rays. Should changes not been seen on x-rays then either CT scan or arthroscopy may be required. CT scan gives a 3-D view of the bones of the elbow joint allowing the bony fragments to be seen, whilst arthroscopy uses a camera to look inside the joint and treat the condition in a single step.

The gold-standard for diagnosis and management of elbow dysplasia and fragmented medial coronoid process is arthroscopy, with any further management of the joint based on the changes identified. Occasionally cutting of the bone at the back of the forearm (bi-oblique proximal ulnar osteotomy, proximal abducting ulnar osteotomy) will ease the tension across the joint and alter the weight bearing through the joint onto healthy cartilage.

The prognosis for return to function is good, with 60-70% of patients having resolution of the lameness, despite the inevitable progression of osteoarthritis. The outcome however will be largely dependent upon the degree of damage within the joint at the time of surgery.

Complications following arthroscopy are very low, with an expected quick post-operative recovery, and improvement of function in the weeks following the procedure. The joint will have some swelling following the surgery, but this should resolve without issue in 2-5 days. Infection is the most common complication (usually less than 2%) which should be monitored for following surgery, and is generally easily treated with antibiotics, but in serious infections, washing of the joint with sterile saline may be required.

Long-term options for the management of elbow dysplasia are based on the maintenance of lean body condition, physiotherapy, joint supplementation (fish oils, glucosamine, chondroitin, pentosan polysulphate injection), joint anti-inflammatories and exercise moderation.