Patellar luxation — dislocation of the kneecap — is one of the most common orthopaedic conditions in dogs, particularly in small breeds. Understanding its causes, welfare impact, and treatment options helps owners provide appropriate care.
Patellar luxation welfare impact is grade-dependent. Grade I-II PL, particularly in small breeds, may cause occasional intermittent discomfort — the characteristic "skipping" gait as the kneecap briefly dislocates and reduces — without sustained welfare compromise in well-managed dogs. Grade III-IV PL represents more significant welfare harm: permanent or near-permanent kneecap displacement causes abnormal limb loading, chronic muscle and tendon stress, and progressive degenerative joint disease with associated pain. The heritable nature of PL means it is substantially preventable through responsible breeding — breeding from affected dogs, particularly those with Grade II-IV disease, perpetuates a condition that causes unnecessary suffering in subsequent generations. The role of breed standards in creating conformational features (short legs, abnormal limb angulation) that predispose to PL is an important ethical consideration in breed reform discussions. Surgical correction, when indicated, typically achieves very good outcomes with most dogs returning to comfortable mobility.