Your 7-month-old Labrador pup has developed a limp. Through observation and a physical exam, your veterinarian suspects a condition called osteochondritis dissecans and wants to take an x-ray of your dog's shoulder joint. You've heard of dysplasia, arthritis, and other bone conditions, but not osteochondritis dissecans. Here's what you need to know about this condition and how to treat it if your dog is diagnosed with it.
What Is Osteochondritis Dissecans?
Osteochondritis dissecans (OCD) is an abnormality in the cartilage of a dog's joint, most often the shoulder, although it can also occur in the hip, knee, or elbow. It is caused by a developmental condition called osteochondrosis, which disrupts the normal process of turning cartilage into bone (ossification) in the joints of an immature dog. In dogs with osteochondrosis, normal wear and tear can lead to the formation of a lesion that can eventually turn into a flap of cartilage within the joint. This flap is what differentiates osteochondrosis from the more painful OCD. Often, these flaps will break off and become what is known as a mouse, which causes additional pain as it travels around the joint capsule. A mouse usually is reabsorbed by the enzymes in the fluid surrounding the joint. But sometimes, it will calcify and continue to cause pain or become lodged in the joint tendons causing acute pain.
What Are the Risk Factors?
Large, fast-growing breeds such as golden retrievers, Great Pyrenees, Labradors, mastiffs, and German shepherds are most likely to get this condition. Other factors include genetics (dogs with OCD should not be bred); age (usually diagnosed in young dogs less than a year old); sex (more common in males); and diet (diets high in calcium, phosphorous and protein can cause rapid bone growth). Trauma can also lead to the development of OCD.
How Is OCD Diagnosed?
First signs of canine OCD typically appear between 4 and 7 months of age. Your pup will start limping and it'll worsen after exercise. The limb will be stiff after resting, and the joint will be painful on palpation. It will oven occur in both limbs simultaneously, although not necessarily to the same degree. Radiographs, most likely using contrast dye, will help pinpoint the lesion and if a mouse has calcified, it will show up as well.
What Is the Best Treatment?
The method of treatment will depend on the stage it is caught and the severity. If only a small flap is present, conservative treatment such as weight loss, controlled exercise and joint supplements such as glucosamine and chondroitin to help repair and maintain the joint cartilage are indicated. Pain medications may also be called for. Such cases should be closely monitored to ensure the condition doesn't get worse.
If a large OCD flap is present, surgery is the treatment of choice to attain a good long-term prognosis. The flap is surgically removed and the cartilage is and the area where it was removed is prepared so that fibrocartilage regrows and fills in the fissure. Usually this can be performed arthroscopically to lessen the scarring and speed up healing. If a mouse is present, it is removed.
After surgery, you'll need to confine your dog to restrict movement of the leg. After 4 weeks, physical therapy exercises can be introduced to strengthen the muscles around the joint. Regular exercise can be resumed gradually over the next month. Joint supplements are recommended to slow or prevent the formation of secondary progressive arthritis. It's also important to maintain a proper weight to avoid extra stress on the joint.
Check with places like Pitts Veterinary Hospital PC for more information.