Patellar luxation — dislocation of the kneecap — is one of the most common orthopaedic conditions in dogs, particularly small breeds. It ranges from incidental to severely painful and is highly amenable to surgical correction when appropriate.
PL welfare impact is directly related to grade: Grade 1-2 dogs may have minimal pain and functional impairment, while Grade 3-4 dogs experience significant chronic pain and disability that limits normal activity, exercise, and quality of life. The intermittent skipping gait of Grade 2 PL is a behavioural pain response — the dog is lifting the affected limb to allow the patella to reduce. Grade 3-4 dogs living without surgical correction experience daily pain that restricts movement and reduces quality of life. The good news is that PL is highly treatable: surgical correction in appropriate cases provides excellent outcomes and restores normal comfort and mobility. Breeding dogs with high-grade PL perpetuates unnecessary welfare harm in offspring — a preventable harm that responsible breeding practices can largely eliminate.