Evaluating forelimb lameness in juvenile dogs - DVM
  • SEARCH:
News Center
DVM Featuring Information from:

ADVERTISEMENT

Evaluating forelimb lameness in juvenile dogs
Find out which conditions are most likely and get general guidance on their diagnosis and treatment. (Part 1 of a 2-part series)


DVM360 MAGAZINE


Elbow dysplasia

Lameness localized to the elbow joint is usually the result of elbow dysplasia. The term dysplasia is used to define osteoarthrosis of the elbow resulting from one or more of the following: incongruence, ununited anconeal process, fragmented coronoid process or osteochondritis dissecans (OCD) of the humeral condyle. Elbow dysplasia is a polygenetic heritable disease in which one proposed pathogenesis includes incomplete ossification or bony fusion of the anconeus or medial coronoid process to the rest of the ulna. Premature distal antebrachial growth plate closure also can lead to joint incongruence and abnormal wear on articular surfaces.


Figure 2: Radiographs of a young dog with elbow dysplasia—lateral (top left), cranio­caudal (top right) and hyperflexed lateral (immediately above) views are recommend­ed. Note the osteophytes associated with the head of the radius and along the anco­neal process, the sclerosis of the ulnar notch and incongruence present and the small osteochondritis dissecans (OCD) lesion on the medial humeral condyle indicated by the arrow.
Elbow dysplasia is common in rottweilers, Bernese mountain dogs, German shepherds, Labrador and golden retrievers and Newfoundlands 5 to 10 months old. Signs include intermittent or persistent weight-bearing forelimb lameness, a head-bobbing gait, decreased range of motion and joint effusion. Affected dogs often have an elbows-out stance. Most dysplastic dogs have bilateral disease. Radiography and computed tomography are used for diagnosis (Figure 2).

Treatment can be medical or surgical but often involves both. Medical management consists of weight control, controlled exercise and administration of NSAIDs, analgesics and chondroprotectives. Surgical management includes either open or arthroscopic exploration of the joint, removal of fragments and débridement of fibrillated or malacic cartilage. It is imperative that surgical treatment be followed with good medical management.

All dogs with elbow dysplasia develop arthritis over time and eventually demonstrate some degree of lameness. All will require medical arthritic management for their lifetimes. Surgery is most helpful when dogs are young and still growing and have minimal or no arthritis. Arthroscopy provides a minimally invasive means to explore the joint and treat several components of elbow dysplasia with generally greater success than conventional surgical techniques.

Osteochondritis dissecans


Figure 3: A lateral radiograph of the shoulder in a young dog demonstrating flattening of the caudal humeral head consistent with shoulder OCD (arrow). This view is best obtained under sedation to facilitate positioning so that the shoulder is not superimposed over the thorax and sternum.
The most common cause of forelimb lameness localized to the shoulder is OCD, which results from a disturbance of articular or epiphyseal cartilage growth characterized by slow ossification of deep zone cartilage, leading to thickened, poorly nourished articular cartilage susceptible to trauma experienced with normal weight-bearing. A dissection lesion develops between the subchondral bone and articular cartilage, resulting in the characteristic flap.


Figure 4: An arthroscopic image of the caudal humeral head with large OCD flap.
OCD affects large-breed dogs, including Labradors and golden retrievers, rottweilers, Saint Bernards, German shepherds and Bernese mountain dogs, that are 5 to 10 months old. Most dogs with shoulder OCD have bilateral disease. Signs include forelimb lameness, adduction of the elbow, muscle atrophy over the scapula and pain with flexion and extension of the shoulder. The typical radiographic appearance is that of flattening and sclerosis of the caudal humeral head (Figure 3).

Treatment involves débridement of the cartilage flap and fragmented, malacic cartilage, followed by débridement of the lesion to the subchondral, bleeding bone via an open arthrotomy or arthroscopy (Figure 4). Arthroscopy provides a minimally invasive means to explore the entire shoulder joint, remove the cartilage flap and débride the cartilage defect with generally more rapid recovery than conventional surgical techniques. The prognosis for a dog with an appropriately treated shoulder OCD is good, and clinically significant osteoarthritis in the future is uncommon.

In part two of this series, I will review common causes of lameness in the hindlimb.

Dr. Janice Buback is a surgeon with Lakeshore Veterinary Specialists in Port Washington, Glendale and Oak Creek, Wis. She and her family, including Angus and Pinot (a.k.a. "Steak and Wine"), enjoy working and playing in southeast Wisconsin.


ADVERTISEMENT

Source: DVM360 MAGAZINE,
Click here