Patellar luxation is a common condition in dogs. The patella (knee cap) should run in a groove at the end of the femur (thigh bone). In some dogs the patella can luxate (dislocate) to the inside (medial) or outside (lateral) of the leg. Most commonly we see dogs with a medial patellar luxation. More commonly we see patellar luxations in small breed dogs like Yorkshire Terriers, Chihuahuas, and Cavalier King Charles Spaniels, however we also recognise the problem in large breed dogs like Labradors and Staffordshire Bull Terriers.