Patellar Luxation in Dogs: Why Some Kneecaps Slip Out of Place

A dog who suddenly skips on a back leg, holds the leg up for a few steps, then goes back to walking normally may be showing signs of a luxating patella. This condition happens when the kneecap, or patella, slips out of its normal position.

Patellar luxation in dogs is a common orthopedic problem, especially in small breeds, although larger dogs can be affected too. Some dogs have mild signs that come and go. Others develop pain, lameness, arthritis, or difficulty using the leg normally.

Understanding what patellar luxation is, why it happens, and when treatment may be needed can help pet parents recognize knee problems early and seek the right veterinary care.

What Is a Luxating Patella?

The patella is the small kneecap that sits at the front of the knee joint. In a healthy knee, the patella glides smoothly within a groove as the dog bends and straightens the leg.

With patellar luxation, the kneecap moves out of that groove. Most often, it slips toward the inside of the leg, which is called medial patellar luxation. Less commonly, it may slip toward the outside of the leg.

When the kneecap shifts out of place, the dog may briefly lose normal knee function. This can cause skipping, hopping, limping, or sudden lifting of the back leg.

Why Do Some Dogs’ Kneecaps Slip?

Patellar luxation often develops because of the way a dog’s leg is built. The bones, muscles, tendons, and groove that guide the kneecap may not line up perfectly. When this happens, the patella is more likely to slide out of place.

Contributing factors to patellar luxation in dogs may include:

• A shallow groove where the kneecap sits
• Abnormal limb alignment
• Genetic or breed-related structure
• Muscle or tendon alignment issues
• Previous injury or trauma
• Developmental orthopedic problems

Many dogs are born with a structural tendency for patellar luxation, even if signs don’t appear until later. In some dogs, trauma can also contribute to kneecap instability.

Which Dogs Are Most at Risk?

Patellar luxation is especially common in small and toy breeds, including Yorkshire Terriers, Toy Poodles, Chihuahuas, Pomeranians, Maltese, and other small companion breeds.

However, any dog can develop this condition. Large-breed dogs may also be affected, and patellar luxation in larger dogs can sometimes be associated with more complex orthopedic concerns.

Because the condition can be inherited, dogs with patellar luxation should be evaluated carefully before breeding.

Signs of Patellar Luxation in Dogs

The classic sign of patellar luxation is a dog who briefly skips or carries one back leg, then returns to normal walking. Some pet parents describe it as a “hitch” in the step or a few hopping strides.

Signs may include:

• Skipping on a back leg
• Holding one rear leg up briefly
• Intermittent limping
• Sudden hopping during walks or play
• Kicking the leg backward to pop the kneecap back into place
• Stiffness after activity
• Reluctance to jump or climb stairs
• Weakness or reduced muscle in the affected leg
• Pain or sensitivity around the knee
• Limping that becomes more frequent over time

Some dogs have mild luxation and very few symptoms. Others may become painful or develop more consistent lameness.

Why Patellar Luxation Matters

A slipping kneecap is not just a quirky gait. Over time, repeated movement of the patella out of place can irritate the joint, affect how the dog uses the leg, and contribute to arthritis.

Dogs with patellar luxation may also place abnormal stress on other knee structures. In some cases, patellar luxation may occur along with other knee problems, including cranial cruciate ligament injury.

Even if signs seem mild at first, it is worth having your dog evaluated. Early diagnosis can help pet parents understand the severity of the condition and what monitoring or treatment may be appropriate.

How Veterinarians Diagnose Patellar Luxation

Veterinarians often diagnose patellar luxation during a physical and orthopedic exam. Your veterinarian will feel the knee, evaluate how the kneecap moves, check for pain or instability, and watch how your dog walks.

Your veterinarian may also recommend X-rays to evaluate the knee, leg alignment, arthritis, or other orthopedic concerns. In some cases, your veterinarian may recommend additional imaging or a referral to a veterinary specialist.

Patellar luxation is commonly graded based on how easily the kneecap moves out of place and whether it stays out of position. The grade helps guide treatment recommendations.

Grades of Patellar Luxation

Veterinarians often describe patellar luxation using grades from mild to severe.

Grade I: The kneecap can be moved out of place during an exam but usually stays in its normal position during daily activity.

Grade II: The kneecap slips out of place at times but can return to normal on its own or with movement.

Grade III: The kneecap is out of place most of the time but can be manually moved back into position.

Grade IV: The kneecap remains out of place and cannot easily be returned to its normal position.

The grade is only one part of the picture. Your dog’s pain, lameness, age, activity level, arthritis, limb alignment, and overall comfort also matter.

Does Every Dog With Patellar Luxation Need Surgery?

Not every dog with patellar luxation needs surgery. Some dogs with mild cases and minimal symptoms may be managed with monitoring, weight management, activity adjustments, exercise guidance, and, when appropriate, pain control.

However, surgery may be recommended when a dog has:

• Frequent limping or skipping
• Pain
• Worsening lameness
• Higher-grade luxation
• Difficulty using the leg
• Progressive arthritis
• Reduced quality of life
• Other orthopedic problems affecting the knee

The decision depends on the individual dog. Your veterinarian or veterinary surgeon can explain whether conservative management or surgical correction is the better option.

What Surgery May Involve

Surgery for patellar luxation helps the kneecap stay in a more normal position and improves knee function. The exact procedure depends on the dog’s anatomy and the severity of the luxation.

Surgical correction may involve deepening the groove where the kneecap sits, adjusting the patellar tendon attachment point, tightening or releasing soft tissues, or addressing limb alignment concerns.

Because each case is different, surgical planning is based on the dog’s exam findings, imaging, luxation grade, and overall orthopedic health.

Recovery After Patellar Luxation Surgery

Recovery after patellar luxation surgery takes time and commitment. Dogs typically need restricted activity, medications, follow-up exams, and a gradual return to normal movement.

Pet parents may need to help with:

• Leash-only walks
• Preventing running and jumping
• Using crates, gates, or small rooms for rest
• Giving medications as prescribed
• Monitoring the incision
• Attending recheck appointments
• Following exercise or rehabilitation instructions

Rehabilitation may be recommended to help rebuild strength, support proper movement, and improve comfort during recovery.

Weight Management and Patellar Luxation

Maintaining a healthy weight is especially important for dogs with knee problems. Extra weight places more stress on the knees, hips, and other joints. For dogs with patellar luxation, excess weight may worsen discomfort and make it harder for the dog to move normally.

Weight management can help reduce strain on the affected knee and support long-term mobility. Your veterinarian can help determine your dog’s ideal weight, daily calorie needs, and a safe plan for gradual weight loss if needed.

Helping Your Dog at Home

If your dog has patellar luxation, home support can make a difference. Depending on your dog’s condition, your veterinarian may recommend:

• Keeping your dog at a healthy weight
• Avoiding repeated jumping from furniture
• Using ramps or steps
• Keeping nails trimmed
• Using non-slip rugs or runners
• Providing controlled, regular exercise
• Avoiding sudden increases in activity
• Following pain-management recommendations
• Scheduling rechecks if symptoms worsen

Do not give human pain medications to your dog unless your veterinarian specifically instructs you to do so.

When to Seek Veterinary Care

Schedule a veterinary evaluation if your dog is skipping, limping, holding up a rear leg, avoiding stairs, or showing signs of knee pain.

Seek more urgent care if your dog suddenly cannot use the leg, seems very painful, has swelling, has experienced trauma, or has a limb that appears unstable or abnormal.

If your dog’s symptoms are getting worse or your family veterinarian recommends advanced orthopedic evaluation, specialty care may help determine the best next step.

Specialty Care for Dog Knee Problems

At Oakland Veterinary Referral Services, our specialty veterinary care team works with pet parents and primary veterinarians to evaluate and treat orthopedic conditions, including complex knee problems.

A dog with patellar luxation may need advanced diagnostics, surgical consultation, pain management, or coordinated care if other orthopedic issues are present. The goal is to help your dog move more comfortably and maintain the best possible quality of life.

If your dog is limping, skipping, or showing signs of knee pain, contact your family veterinarian or OVRS for guidance.