For the most part, Patellar Luxation, also known as Slipped Stifle, 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 rear leg, slips. Sometimes it corrects itself, sometimes your vet can put it back in the groove, and sometimes it may require surgery. Many veterinarians believe that if not surgically corrected, osteoarthritis will eventually develop.
What causes slippery knee?
It is believed to be a genetic deformity of the femur (thigh bone), tibia (shin bone), and knee joint (patella). Normally, the patella slides smoothly and safely in the femoral groove. In affected dogs, the groove is shallow and/or misshapen. The ligaments that hold the patella in place become weak, making the angulation between the femur and tibia irregular and unstable. When your dog runs, turns, jumps up or down, the kneecap slips out of the groove.
Another cause can be trauma, as it can also damage the joint, weakening the ligaments out of alignment.
Signs to watch out for:
It most often occurs when your dog runs amok around the yard, or jumps for a Frisbee ball. While in the air, they will yelp in pain, often spinning around biting their hind leg as they lift it off the ground. They will often walk with a limp for 10 to 30 minutes; then they return to normal.
You will notice:
Mood swings…can become abrupt 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 the risk of arthritis.
Since Slipped Stifle is inherited by a defective 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 less weight-bearing exercises, 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 toy terrier
It should be noted that 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 too much damage has been done to your joints.