Here's a scenario for you to think about. Your child is out in the back yard, running about with your 1-year old dog, when unexpectedly, you hear that dog yelp in pain. Wasting no time, you head out the door and observe that the dog appears to have an injured hind leg, holding it aloft as it trots along on the other three. As if by magic, the dog starts running again on all fours like normal, appearing that nothing had been wrong in the first place.

To add to this scenario, it dawns on you that you have noticed this behavior becoming more and more frequent so now you are concerned enough that you wonder if you should call your veterinarian and make an appointment. Stop wondering and make the call. Your cherished pooch is most likely the victim of a luxated patella, or more simply, a lipped kneecap (or trick knee).

This discomforting malady is hereditary and causes the kneecap to move out of its normal position (dislocates), typically shifting towards the inside of the animals leg. Additionally, it normally occurs in both of the back legs but to a more severe degree in one than the other. When the dogs kneecap is positioned normally, it sits within a deep groove where it slides down and up in a controlled manner.

As this groove gets more and more out of shape or becomes increasingly shallower, the kneecap begins to slip out of its normal position more frequently. The leg then locks up, causing the foot to be elevated off the ground. As a result, the dog cries out from the discomfort that results. Typically, the condition is more common in the smaller breeds of canines than the medium-sized or larger ones. The result of the conditions onset is immediate lameness and pain.

In less severe cases, the kneecap slides freely in and out of position voluntarily, but as the condition becomes increasingly more severe, the dislocation can become permanent requiring a vet to either pop the kneecap back into place or, in the most severe cases, correct the condition surgically. Also, as the condition worsens, the knee capsule itself is injured and the dog appears to be bowlegged.

As we mentioned above, the condition doesn't just happen overnight, although the initial onset of it would make the owner of the animal speculate as such. Luxated patella is an inherited condition and is most likely present when the puppy is born. Fortunately, the condition is not crippling even in its most severe stages. The worst case scenario is that it will have to be surgically repaired and your dog should be able to live a happy and normal life afterwards.

As a final cautionary note, assuming that this condition is inherent to the breed of dog and then neglecting to take action is a huge mistake with unpleasant consequences. In younger dogs, not taking care of this oftentimes results in torn ligaments or more severe damage to the knee. In older canines, neglecting the condition has been known to lead to diseases in the bones and the joints as well as causing arthritis. So please, don't gamble with your dogs well-being get the condition corrected immediately.