Patellar luxation is a common cause of hindlimb lameness in small breed dogs, with welfare implications for both affected individuals and the breeding practices that perpetuate the condition.
Patellar luxation welfare impacts range from occasional discomfort in mild cases to severe, constant pain and inability to bear weight in advanced grades. The sudden onset of luxation causes the characteristic "skipping" gait — the dog lifts the leg to allow the patella to return to position — which is clearly an acute pain event. Repeated luxation episodes cause progressive cartilage and soft tissue damage, increasing pain and progression to higher grades without treatment. The welfare case for surgical correction of grade 2-4 luxation is strong — most dogs show dramatic improvement and return to normal activity. The breeding welfare issue is significant: knowingly breeding dogs with hereditary patellar luxation perpetuates suffering in subsequent generations.