Patellar luxation is one of the most common orthopedic conditions in small and toy dog breeds, causing intermittent to chronic pain and mobility impairment that requires appropriate management.
Luxating patella causes a specific pattern of welfare harm: brief acute pain during luxation events, followed by chronic low-level joint pain from repeated cartilage damage. Dogs adapt behaviorally to intermittent lameness in ways that mask their pain from owners, delaying treatment. The breeding welfare issue is significant — selection for extreme compact conformation in toy and miniature breeds has made patellar luxation essentially an expected feature of some breeds rather than an unusual individual pathology. This normalizes preventable suffering. Welfare-focused breeding programs that select away from conformations predisposing to luxation would reduce the prevalence of this condition across generations.