Key Points
- Patellar luxation is a condition where a dog’s hind kneecap(s) pops out of the joint.
- Severity ranges from stages I-IV, and higher degrees of deformity are more likely to require surgery.
- Dogs with patellar luxation may develop an abnormal run or yelp in pain when walking.
You may notice your dog walking with a funny-yet-endearing limp or seeming a little stiff after hours of curling up by your side. Your tail-wagging warrior may even run on three legs or leap off stairs and yelp in pain. In these instances, your pup may be dealing with patellar luxation.
In simple terms, patellar luxation is when a dog’s kneecap pops out of the joint. Treatment options for this genetic condition range from medication and physical therapy to surgery, so it’s important to meet with your veterinarian to consider the best course of action.
Symptoms
Often, symptoms of patellar luxation can be subtle at first. According to VCA Hospitals, “Pet owners may notice a skip in their dog’s step or see their dog run on three legs; then, suddenly, she will be back on all four legs as if nothing happened.”
Other symptoms of luxating patella in dogs may include:
- Abnormal gait
- Crying out when walking
- Kicking their legs out when running
- Lethargy
- Visible swelling
- Weak joints
- Worsening symptoms after extended periods of rest
Causes
Patellar luxation underscores the importance of veterinary consultation prior to breeding, as the most common cause is a genetic abnormality. Less commonly, traumatic accidents may cause the kneecap to pop out of alignment.
- Genetic deformity: Patellar luxation is most commonly caused by a genetic abnormality. The patella is located in the trochlear groove at the distal femur and is supported by the joint capsule, patellar ligament, and various other tendons, ligaments, joint fluid, and muscles. Most commonly, the trochlear groove is too shallow due to excessive mobility from a patella that is positioned too high or too low, poor hip conformation, or other limb malalignments.
- Trauma: Cranial cruciate ligament rupture or damage to the kneecap’s many substructures may lead to patellar luxation. In these cases, lameness comes on rather suddenly and persists, rather than coming and going intermittently.
While obesity and poor nutrition do not directly cause luxating patella in dogs, they are considered risk factors.
Diagnosis
Dr. Corinne Wigfall, CBMBVS, a registered veterinarian and consultant with SpiritDog Training, explains that patellar luxation can be graded from I-IV in severity, depending on how easily the kneecap displaces from the trochlear groove, the position of the patella, and the degree of bone deformity.
She looks for the following clinical signs and symptoms in diagnosing patellar luxation:
- Grade I – The patella can be manually luxated out of the groove by applying pressure to it. It will then spontaneously return to its normal position once the pressure is removed.
- Grade II – The patella may displace without pressure being applied on its own when the dog walks. It may remain displaced until the hindlimb is extended or rotated, then return to its normal position.
- Grade III – The patella may be out of the groove most of the time, but it can be replaced to its normal position with manipulation. It may then displace immediately after repositioning.
- Grade IV – The patella is always displaced out of its groove and cannot be replaced with manipulation. These patients may have severely bow-legged anatomy.
Dr. Wigfall adds that approximately half of the affected dogs will have both hindlimb kneecaps affected, though the grades of patellar luxation may vary from one limb to the other.
Treatment
Treatment options for dogs with patellar luxation may include some or all of the following:
- Surgical correction
- Pain medication
- Anti-inflammatories
- Acupuncture
- Weight loss
- Physical therapy
- Hydrotherapy
- Cortisone shots
“Not every grade for luxation requires surgery, despite the severity of the grade,” says Dr. Shadi Ireifej, DVM DACVS, chief medical officer, founder, and owner of VetTriage telehealth services.
He explains that surgical correction varies widely depending on the patient’s abnormalities, but most commonly includes:
- Trochleoplasty – deepening the trochlea groove
- Imbrication – tightening the joint capsule over the aspect opposite of the luxation’s direction
- Release – loosening the joint capsule over the direction and aspect of the luxation
- Tibial tuberosity transposition – realigning the tibial crest that holds the patella in place
Before choosing a treatment path, your family will need to consider:
- The financial investment, as surgeries can range from a few thousand dollars to $5,000+
- Medical comorbidities of the patient, with Cushing’s disease and diabetes affecting healing
- Neurologic conditions, which may make your pet more accident-prone during recovery
- Complications in the limb, such as arthritis or recurrent ligament tears
- Quality of life, whether it diminishes the dog’s day-to-day comfort and happiness
- The risk of anesthesia, particularly with older dogs or those who have cardiac disease
- Concurrent orthopedic issues, such as elbow arthritis, hip dysplasia, or limb amputation
Dr. Shadi adds, “In order for a pet owner to make the correct decision, they need to balance the pros and cons of the proposed treatment, which is the main crux of the discussion they have with their family veterinarian.”
Recovery and care
More than 90% of dog owners are satisfied with the outcome of patellar luxation surgery, according to the American College of Veterinary Surgeons. With proper care, dogs can begin bearing weight on their healing leg within six to eight weeks of surgery.
Most dogs live normal, active lives after surgery, especially when they are graded I-III and the condition was diagnosed early. Outcomes may be less optimal for larger dogs with other abnormalities like hip dysplasia or for those with a grade IV diagnosis.
Long-term care recommendations may include daily medication and physical therapy.
Prevention
As Dr. Jamie Whittenburg, DVM, a veterinarian at SeniorTailWaggers.com and Director of Kingsgate Animal Hospital in TX, points out: “The first step to preventing patellar luxation is responsible breeding. Breeders should enlist the help of a veterinarian to perform the necessary health testing prior to breeding. Dogs with a history of MPL and/or poor conformation should not be bred.”
If your beloved pup is predisposed to the condition, Dr. Whittenburg emphasizes, “It is imperative to keep them at a healthy lean weight, to avoid letting them jump up and down from excessive heights, and to provide high-quality nutrition.” Your veterinarian may recommend joint supplements, injections, or specialized diets that may help.
What to expect at the vet’s office
When you bring your furry friend in for a physical examination, your vet will begin by asking a few basic questions about your pet’s symptoms and lifestyle, such as:
- How long has your dog been limping?
- Do you notice increased limping after long periods of rest?
- Does your dog seem lethargic or less active than other dogs?
- Does your dog leap off the stairs, into the car, or onto and off of furniture often?
- What type of food does your dog eat, and how much exercise does your pet get?
Next, your vet will perform an orthopedic exam, which includes manipulating the patellae. Higher grade luxating patella are generally easy to palpate on exam, while Grade I or II luxation may be more difficult to diagnose. In some cases, diagnostic testing with an x-ray or CT scan can help assess the nature of the condition. Your vet may also recommend additional tests such as blood work or urinalysis if your pet requires long-term medication or surgical correction.
Many dogs are able to lead healthy, happy lives, despite their patellar luxation. The right pet insurance plan can help you give your pooch the best care for unexpected conditions they may encounter along the way.
FAQs
How much does it cost to treat patellar luxation?
According to veterinarian and Pango Pets consultant Dr. Paola Cuevas, MVZ, patellar luxation surgery can cost anywhere between $1,000 to $5,000 per affected knee. On top of routine veterinary checkups, the postoperative care may also include $20-$50 in monthly medication, as well as physiotherapy and hydrotherapy. “The rehabilitation alone can run anywhere from $40 to $100 per session, which is why inquiring about a pet insurance plan for dogs is recommended,” she says.
Does pet insurance cover patellar luxation?
Pet insurance can help you afford the cost of eligible vet bills if your dog gets sick or hurt, and this may include treatment for patellar luxation. However, if your dog is showing signs of patellar luxation before you purchase a pet insurance plan, it may not be eligible, since most pet insurance providers don’t cover treatment for pre-existing conditions.
How should I treat my dog’s patellar luxation?
Before attempting treatment for patellar luxation, you should always consult your local vet to hear their opinions as a veterinary medicine expert. The best treatment decisions will be based on the severity of the condition and your pet’s comfort, but you’ll also need to consider how challenging the recovery process might be, given your pet’s age, disposition, and general health.
Did you know?
- Patellar luxation is one of the most common orthopedic conditions in dogs, affecting 7% of puppies, especially Boston Terriers, Yorkies, Chihuahuas, Pomeranians, and Poodles.
- One study found that 40% of Flat-Coated Retrievers were affected by a degree of patellar luxation.
- Surgical treatment has a 90% success rate, with a “good” to “excellent,” complication-free outcome.
