Explainer

Luxating Patella in Dogs: The 'Skipping' Kneecap

A dislocating kneecap is common in small breeds and causes a 'skip' in the step. The four grades, when surgery is needed and what recovery looks like.

Updated October 2026 · 6 min read · By the Hushku editorial team · 2 sources

Short answer

A luxating patella is a kneecap that slips out of its groove. Dogs typically 'skip' for a few steps, holding up a back leg, then carry on normally. It's very common in small breeds like Chihuahuas, Pomeranians, Yorkshire Terriers and Toy Poodles. Mild cases are monitored; surgery is usually considered for grade 2 and above when it causes lameness, and over 90% of owners are satisfied with the result.

Key facts

The classic sign is 'skipping' for a few steps on a back leg.
Most common in small breeds like Chihuahuas, Pomeranians and Yorkies.
Surgery is usually considered from grade 2 upwards.
Over 90% of owners are satisfied with the result of surgery.

Definition

Patellar luxation is a condition in which the kneecap (patella) moves out of its normal position in the groove at the end of the thigh bone (femur), usually towards the inside of the leg (medial luxation).

The kneecap normally glides up and down in a groove at the bottom of the femur. In dogs with patellar luxation, the groove may be too shallow, or the bones and muscles of the leg may be slightly misaligned, so the kneecap pops out of place.

According to the American College of Veterinary Surgeons, it mainly affects small breeds, including Boston and Yorkshire Terriers, Chihuahuas, Pomeranians and Miniature Poodles. Some large breeds, including the Chinese Shar Pei, Flat-Coated Retriever, Akita and Great Pyrenees, are also now considered predisposed. It's usually developmental and often affects both knees.

The classic sign is "skipping": your dog suddenly holds a back leg up for a few steps, may kick or stretch the leg out, and then uses it normally again once the kneecap slips back into place.

Signs and symptoms

A 'skip' or hop for a few strides, then normal walking
Holding a back leg up, or kicking it out behind
Bow-legged appearance in severe cases
Lameness that becomes more frequent or constant over time
Stiffness or pain as arthritis develops

Causes and risk factors

A shallow groove in the femur
Misalignment of the leg bones or the attachment of the thigh muscles
Genetics: it runs in families and in certain breeds
Less often, injury

Treatment

Monitoring, weight control and exercise to build thigh muscle for mild cases without signs
Pain relief and joint support if arthritis develops
Surgery to deepen the groove, realign the shinbone attachment and tighten the soft tissues
Strict rest for several weeks after surgery, followed by gradual rehabilitation

Prevention

Choose puppies from parents screened for patellar luxation
Keep your dog lean
Build muscle with regular, steady exercise rather than lots of jumping

The four grades

Grade 1: the kneecap can be pushed out by hand but returns on its own. Grade 2: it pops out on its own when the knee bends, and goes back when the leg is extended. Grade 3: it's out of place most of the time but can be pushed back by hand. Grade 4: it's permanently out of place and can't be pushed back, often with obvious deformity. ACVS notes surgery is most often considered for grade 2 and above, depending on the signs.

Outlook

ACVS reports that over 90% of owners are satisfied with their dog's progress after surgery, and recurrence is uncommon. Results are less favourable in large dogs, especially with other problems such as hip dysplasia or significant bone deformity.

Cruciate ligament risk

A kneecap that keeps slipping puts extra strain on the knee and is thought to increase the risk of cruciate ligament injury, another reason to have persistent skipping checked.

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Sources

We check guides against veterinary sources and update them when guidance changes. How we write and review.

Questions.

Is a luxating patella painful?

Many dogs with mild luxation show no pain. As it worsens or arthritis develops, it can become painful.

Can a luxating patella fix itself?

The kneecap often slips back by itself, but the underlying problem doesn't go away. Grades can stay stable or worsen over time.

Should a dog with a luxating patella be bred?

It's generally advised not to breed affected dogs, as the condition is inherited.