Patellar Luxation in Dogs: Grades, Surgery & Treatment

If your dog occasionally skips or hops while running, then puts the leg back down and continues normally, you might be dealing with patellar luxation — one of the most common orthopedic conditions in small breed dogs.

What Is Patellar Luxation?

The patella (kneecap) normally sits in a groove at the bottom of the femur. In patellar luxation, the kneecap pops out of this groove, usually to the inside of the leg (medial luxation). This causes the characteristic "skip and pop" — the dog holds up the leg for a few steps until the patella slides back into place.

Which Breeds Are Affected?

Small and toy breeds: Yorkshire Terrier, Chihuahua, Pomeranian, Miniature Poodle, Boston Terrier, Maltese, Pekingese. Large breeds can also be affected (usually lateral luxation). The condition is strongly genetic — affected dogs should not be bred.

The Four Grades

Grade I: Mild

The patella can be manually pushed out of the groove but returns to normal position on its own. The dog may occasionally skip but is otherwise normal. Conservative management is usually appropriate.

Grade II: Moderate

The patella luxates more frequently and may stay out of position longer. The dog skips frequently. There may be early arthritic changes. Surgery is often recommended, especially if clinical signs are frequent.

Grade III: Severe

The patella is out of the groove most of the time but can be manually reduced. Significant lameness and early arthritis. Surgery is definitely recommended.

Grade IV: Very Severe

The patella is permanently luxated and cannot be manually reduced. Severe limb deformity, persistent lameness, and advanced arthritis. Surgery is essential but more complex.

Treatment Options

Conservative Management (Grade I, some Grade II)

Weight control (the single most important factor), joint supplements (glucosamine, chondroitin, omega-3 fatty acids), physical therapy to strengthen quadriceps muscles, moderate controlled exercise, avoiding jumping and high-impact activity, NSAIDs for pain during flare-ups.

Surgical Correction (Grade II-IV)

Trochleoplasty: Deepening the groove the patella sits in so it cannot slip out.

Tibial tuberosity transposition: Moving the attachment point of the patellar tendon to realign the quadriceps mechanism.

Soft tissue procedures: Tightening or releasing the joint capsule to stabilize the patella.

Femoral osteotomy: Correcting bone deformity in severe cases.

Most surgeries combine 2-3 of these techniques. Success rate is 90%+.

Surgery Cost

$2,000-$4,000 per knee depending on grade, geographic location, and whether performed by a specialist. Bilateral disease is common (50% of dogs have both knees affected).

Recovery

Cage rest for 6-8 weeks with gradual return to activity. Physical therapy essential for optimal outcome. Full recovery typically 12-16 weeks. Most dogs return to normal or near-normal function.

The Key Decision

When to do surgery vs. conservative management: frequency and severity of clinical signs, progression of the grade over time, development of arthritis on radiographs, age of the dog (younger dogs benefit more from early surgery), and owner's goals and financial considerations.