How to Treat a Cat's Luxating Patella

luxating patella in cats

Luxating patella is an orthopedic condition that affects the stability and functionality of the knee joint. This common knee injury is seen in cats, dogs, and humans.

What Is Luxating Patella in Cats?

Luxating patella occurs when the kneecap is out of place. The term patella refers to the kneecap. The term luxation means dislocated or out of place.

The knee is a complex joint that connects the lower femur (thigh bone) to the higher tibia (shin bone) via muscles, tendons, and ligaments (shin bone). The patella, or kneecap, is a tiny bone that rests in the trochlear groove in the femur beneath the patellar ligament. The patella rides up and down in the trochlear groove when the knee is bent and flexed.

The kneecap may pop in and out of the groove if it is not operating properly. It is difficult to bend and flex the knee joint when the kneecap is out of place. Walking, sprinting, and jumping become unpleasant and difficult for the cat as a result.

A veterinarian diagnoses patellar luxation after palpating the knee joint and ruling out other possible reasons. A luxating patella in one or both knees may be discovered by the veterinarian. The luxation is usually medial, which means it dislocates toward the inside of the knee. The luxation may also be lateral, causing the knee to dislocate to the outside.

The diagnosis of a luxating patella will fall into one of four categories based upon the severity of the dislocation.

  • Grade I: The kneecap can be dislocated from the groove when the vet puts pressure on it, but it goes back in place when the pressure is released. 
  • Grade II: The kneecap intermittently pops in and out on its own. It will remain out of place until the leg is straightened and turned in a way that allows the kneecap to return to the groove. 
  • Grade III: The kneecap is out of the groove most of the time, but the vet can manually move it back into place.
  • Grade IV: The kneecap is permanently out of place and cannot be repositioned by the vet. 

If both knees are affected, each side may have a different degree of severity.

Causes of Luxating Patella in Cats

When the trochlear groove is too shallow to hold the kneecap, patellar luxation can develop. Ligament, tendon, or muscular injuries are additional possible causes. Anatomical deformities such as bow leggedness might induce it in some situations.

The source of disorders that cause patellar luxation is uncertain. Because certain cats may be genetically susceptible to the problem, luxating patella cats should never be bred. Abyssinian, Burmese, and breeds may be more prone to developing luxating patellas.

Signs of Luxating Patella in Cats

  • Intermittent lameness / limping in one or both
  • Licking / chewing around one or both knees
  • Clicking or popping sound on manipulation of affected knee(s)

Symptoms of patellar luxation in cats can come and go. The cat will be able to walk, run, and jump normally if the kneecap is in the appropriate position. The cat will suffer pain and reduced movement in the afflicted knee if the kneecap is out of place.

A cat with a low-grade luxating patella and no symptoms is feasible. During a normal health exam, your veterinarian may notice this and urge you to keep an eye on it.


If your cat is limping, you should see your veterinarian right away. The veterinarian will start by going over your cat's medical history and completing an examination. To rule out other disorders and confirm a diagnosis, radiographs (X-rays) may be required.

Cats with luxating patellas are frequently treated conservatively at first. Rest and exercise restriction may be recommended by your veterinarian, which means you'll need to restrict your cat's access to running and leaping. For a limited duration, anti-inflammatory and pain drugs may be provided.

Your cat will rarely be in pain if the patellar luxation is minimal (particularly Grade I). When the kneecap occasionally comes out of the groove in mild to moderate instances (Grade II), you may observe indications on and off. The cat should be able to have a somewhat normal life in moderate situations. If the knee problems persist, rest and medicine may be required from time to time.

If conservative treatment fails and your cat is in constant discomfort and immobility, surgery may be required. With Grade III and IV patellar luxation, this is frequently the case.

The problems that cause the patella to dislocate are corrected during surgery for patellar luxation. Patellar luxation can be treated using a variety of surgical procedures. The trochlear groove is usually deepened, the soft tissues around the patella are reconstructed, and aberrant bones are occasionally reshaped during surgery.

Recovery from surgery requires rest and pain management at first. Most cats recover quickly but may benefit from some type of gentle physical therapy.

Though it is possible to reinjure the knee joint, most cats will not experience future problems.

How to Prevent Luxating Patella in Cats

Patellar luxation in cats cannot be totally avoided, however it can be reduced. By avoiding damage in general, you may be able to prevent luxating patella in cats. Create smaller stairs if your cat likes to leap up to high areas to reduce knee discomfort.

If your cat is in pain or showing other indications of disease, contact your veterinarian as soon as possible. The sooner you get a diagnosis, the sooner you can start therapy.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.