For the most part, patellar luxation, also known as slipped knee, is a fairly common toy breed and genetic condition of small dogs. It can also be caused by trauma. It occurs when your dog’s “knee” joint, just above the hock on the hind leg, slips. Sometimes it corrects itself, sometimes your vet may put it back in the groove, and sometimes it may require surgery. Many veterinarians believe that if it is not surgically corrected, osteoarthritis will eventually appear.
What Causes Knee Slippage?
It is believed to be a genetic deformation of the femur (thigh bone), tibia (shin bone), and knee joint (patella). Normally, the patella glides smoothly and safely in the femoral groove. In affected dogs, the groove is shallow and / or deformed. The ligaments that hold the kneecap in place weaken, making the angulation between the femur and the tibia uneven and unstable. When your dog runs, turns, jumps up or down, the kneecap comes out of the groove.
Another cause can be trauma, as it can also damage the joint and weaken the aligned ligaments.
Signs to watch out for:
It most often occurs when your dog runs madly across the yard or jumps for a ball, Frisbee. While in the air they will scream in pain, often turning nibbling on their hind leg as they lift it off the ground. They will often walk lame for 10-30 minutes; then they go back to normal.
You will notice:
Mood swings … can become rapid when in pain
Grunts or snaps when you pick them up or touch their hindquarters
Walking on three legs
Even if your dog seems to be back to normal, you should have your vet examine him. They may suggest an anti-inflammatory or glucosamine, but eventually, they will most likely recommend surgery to lower your risk of arthritis.
Since the Slipped Stifle is inherited by a faulty gene, affected dogs must be spayed or neutered so as not to perpetuate the condition.
What you can do to help your pet:
Mild to moderate exercise
Limit strenuous exercise to exercises with less weight, such as swimming.
Breeds predisposed to Slipped Stifle include, but are not limited to:
American cocker spaniel
Cavalier King Charles Spaniel
English cocker spaniel
English toy spaniel
Jack russell terrier
Poodle (toy and miniature)
Manchester Terrier Toy
It should be noted that the larger breeds are not affected. Certain larger breeds, such as Labrador Retrievers, are also prone to Slipped Stifle.
Bottom line: As your dog ages, the problem may become more prevalent and it may take longer to recover. Don’t wait until there is too much joint damage.