A luxating patella (or patellar luxation) is a common orthopedic problem in which a dog’s kneecap dislocates from the normal position. It’s one of the most common genetic problems affecting dogs; in fact, according to ACVS, patellar luxation is diagnosed in about 7% of puppies and is especially common in smaller breeds.
But is patellar luxation painful? What should you do if your dog dislocates a kneecap? Read on for answers to these questions plus information on the causes, symptoms, and treatments for luxating patella injuries.
Table of Contents
- What is a luxating patella in dogs?
- Signs of a luxating patella in dogs
- Patellar luxation treatment options
- Recovery and prognosis
- Key Takeaways
Pro Tip: Pet insurance can cover the cost to treat luxating patellas that develop after policy enrollment. Some of the best pet insurance companies even include coverage for alternative treatments such as hydrotherapy that can be of great help after surgery, so long as it is not a pre-existing condition.
What is a luxating patella in dogs?
Normally, a dog’s kneecap (patella) sits in a groove of the femur bone, sliding up and down when the dog extends or flexes their knee. With patellar luxation, the kneecap tends to dislocate (luxate) outside the thigh bone groove.
Patellar luxation can be a congenital condition, which means that it is passed down from affected dogs to their offspring.
Depending on the direction in which the patella slides, it's classified as either lateral or medial. If the dog’s kneecap is veering to the inside, this is considered a medial luxating patella, which is more commonly seen in veterinary practice than lateral patellar luxation. Medial luxating patella is prevalent in 98% of small dogs, while lateral luxating patella is a bit more common in large dog breeds.
(Image source: VCA Animal Hospitals)
What causes patellar luxation in dogs?
As mentioned before, patellar luxation is a congenital condition. In rare cases, it can be a result of intensive exercise during puppyhood. The reason for this is that certain breeds might grow faster than average and in that case, too much exercise can have a negative impact on bone growth.
Dogs who are overweight or have poor nutrition are also at an increased risk of suffering from joint issues associated with the kneecap due to an increased pressure on the knee joint.
Certain medical conditions and injuries, such as cranial cruciate ligament rupture or pain can also contribute to the development of luxating patella.
Affected breeds
Luxating patella is most prevalent in toy and small breeds weighing under 30 pounds, including:
- Chihuahua
- Boston Terrier
- Toy Poodle
- Miniature Poodle
- Cocker Spaniel
- Yorkshire Terrier
- Pekingese
- Pomeranian
- Lhasa Apso
- Shih Tzu
- Papillon
- Basset Hound
- Cairn Terrier
However, according to the American College of Veterinary Surgeons, the incidence in large breed dogs has been on the rise over the past ten years. Large breeds like Great Pyrenee, Boxer, Saint Bernard, Husky, Golden Retriever, Labrador, German Shepherd, Great Dane, Newfoundland, Cane Corso, and Akita can also be prone to developing luxating patella. In addition, dogs with bowed or dwarfed limbs are at risk of inheriting this defect.
Canine luxating patella signs
Depending on the grade of the disorder, some pups may not show any symptoms of patellar luxation. When symptoms do occur, they might include lameness and limping. Some dogs may skip when running, hold up or shake the affected leg, or yelp in pain. In general, symptoms will become more consistent and frequent as the condition progresses.
In more serious cases, complications can develop such as limited activity due to severe pain, inflammation that might break down the ligament, osteoarthritis resulting from worn cartilage of the knee, etc.
Diagnosis and grades
Luxating patella is often diagnosed after owners notice any symptoms. In order to confirm the diagnosis, the vet will perform a physical examination. In some cases, additional tests might be recommended, such as dog X-rays of the knee to determine the severity of the disease and check for hip dysplasia.
Once a diagnosis is made, the condition is classified into one of four grades depending on the severity:
- Grade I - When the kneecap pops out, it quickly returns to its normal position on its own.
- Grade II- Although the kneecap is in its normal position most of the time, it tends to pop out of place more easily. However, it can be manipulated back into the correct position.
- Grade III - The kneecap is out of its normal position most of the time. When manipulated back into the groove, it will pop right back out.
- Grade IV - The kneecap is out of position all the time and it can't be returned back into the groove.
Patellar luxation treatment options
Non-Surgical treatment options
What treatment your veterinarian recommends will depend on the severity of your dog's patellar luxation. In general, if your pet has grade 1 or 2, your vet will likely recommend non-surgical treatment. The most common non-surgical methods for luxating patella include:
- A knee brace. Many vets recommend knee bracing as an alternative to surgery when the condition is mild. Bracing the knee allows the soft tissue to stabilize and gain elasticity.
- Physical manipulation. Massaging the knee joint can help relieve muscle tension and spasms, manage pain and discomfort associated with mild patellar luxation, and improve your dog’s mobility.
- Supplements. Consult your vet about giving chondroitin and glucosamine supplements. These supplements improve the cartilage and might even improve the fluid available in the knee.
When does luxating patella treatment require surgery?
More severe cases of luxating patella will require surgery. Typically, vets recommend surgery for dogs that have grade 3 or grade 4, but also for dogs with a lower grade who limp frequently (a few times per week). Surgery is also often staged if both of the pup's rear legs are affected. According to VCA Animal Hospitals, about 50% of affected dogs have both knees involved.
Surgery will improve kneecap stability with various techniques that include reinforcing the knee joint's soft tissue structures, deepening the femur groove, and moving the tendon that attaches the shin bone to the patella.
Luxating patella surgery cost
The cost to treat patellar luxation will depend on several factors, including your location of the surgery and who performs the procedure. In general, board-certified veterinary surgeons charge more than general veterinarians due to the fact that they have more advanced training and experience. The surgery can cost between $1,000 and $5,000.
Remember, the surgery itself is not the only cost you should expect — the post-operative care can be quite expensive as well as may involve physiotherapy, hydrotherapy, medication, and vet visit check-ups. Rehabilitation can cost from $40 to $100 per session, whereas pain relief medications can cost between $20 and $50 a month.
Pro Tip: Not having coverage for orthopedic pet conditions like patellar luxation can be problematic as these health issues often require expensive procedures and won’t be reimbursable if your dog doesn’t have pet insurance.
Recovery and prognosis
According to the American College of Veterinary Surgeons, more than 90% of dog owners are satisfied by the progress of their pet after surgery. Most dogs go on to live normal, active lives after surgery, especially those in grades one to three, as well as the cases when surgery was performed early on after diagnosis.
The prognosis is less favorable in dogs with grade four of the disorder, as well as large dogs, especially if other abnormalities like hip dysplasia are present.
With proper care, dogs can start using their recovering leg within six to eight weeks of surgery.
Preventing patellar luxation in dogs
Because luxating patella is a genetic condition, the only way to avoid the condition is to simply not breed dogs who carry the genes for the disorder.
If you have a breed that is prone to developing patellar luxation, the best thing you can do is to:
- Prevent your pup from getting overweight. Overweight dogs with trick knees have more trouble walking and are likely to develop arthritic changes to the knee much faster.
- Provide regular exercise. Besides preventing excess weight, regular physical activity will ensure the muscles that hold their knee in place are strong and healthy.
- Feed your pup a healthy diet. A homemade or raw diet can help improve overall cartilage condition and make the joints healthier.
Key Takeaways
- ‘Patella’ is the scientific term used for the kneecap, and ‘luxating patella’ simply means ‘dislocated kneecap’.
- Patellar luxation can affect any dog breed but is most common in small and toy breeds.
- Most dogs with mild patellar luxation can benefit from non-surgical methods, such as massage and knee bracing, while those with more serious problems often need surgery.
- Most pet parents are satisfied by the progress of their pets after the surgical procedure and the majority of dogs go on to live normal, active lives after surgery.
