When a dog fractures its patella, located where the hind leg bends, veterinarians usually perform surgery. Two bones, the femur and tibia, comprise the stifle joint, which is comparable to the human knee. The patella covers the joint like a knee cap.
A fractured patella cannot protect the stifle joint and prevent the joint from rotating counter-clockwise. Fractures occur most often in immature or young dogs.
Symptoms of a fracture include lameness, swelling at the knee and pain.
Several surgical procedures exist. Veterinarians can surgically reconstruct the knee to improve knee and joint stability using sutures, wires, pins and screws.
Fixating the Patella
The primary goal of surgery is to “fixate” the patella and its adjoining joints, bones and ligaments to prevent improper rotation--often indicated by a “skipping gait” in the dog.
Restore Normal Function
Fractured patella surgery can reshape the bones and restore normal function of the knee. Surgery in smaller dogs might require a single pin to repair the fracture without reshaping the bones; however, in larger dogs, a more elaborate surgery, including a “buttress plate” may be required, according to Dog Health Guide.