How To Spot Maine Coon Patella Luxation

Maine Coon Patella Luxation (Patellaluxation) is a frequently used term when it comes to Maine Coon health and care.

Orthopedic problems are prevalent in the cat world and Maine Coons are no exception. Keep reading to find out how to treat this health problem.

A cat’s knee joint is one of the main weight-bearing joints that provides support and agility. One of the primary structures of a cat’s knee or stifle joint is the patella, an oval-shaped bone. Normally, the patella resides and moves inside a groove but if it gets displaced or pops out of place this condition is known as patella luxation in cats.

Our registered small animal veterinarian Dr Abdul Basit Javed (DVM, RVMP) has written this article to share his knowledge on Maine Coon patella luxation.

He explains everything related to patella luxation in Maine Coons including the symptoms, causes, price of surgery, and more, so read on!

Maine Coon Patella Luxation

Maine Coon Patellar Luxation is when the patella or kneecap is displaced or pops out of the trochlear groove.

The term luxation refers to getting displaced from the normal position.

A Maine Coon’s knee joint is one of the primary joints that play a key role in movements such as:

• Jumping
• Running
• Crouching
• Providing Stability and Support

The knee joint of a Maine Coon comprises three bones:

• Femur
• Tibia
• Patella (knee cap)

These bones are held together with different:

• Tendons
• Ligaments
• Muscles

The patella is the smallest bone forming the knee joint and it resides and moves within a groove known as the trochlear groove present at the distal end of the femur bone.

In about 80% of cats, patella luxation is bilateral, which means it will occur in both knee joints at the same time. The cause can be either:

• Genetic
• Traumatic

According to The International Cat Association (TICA), Maine Coons are the largest domestic cats in the world, with female Maine Coons weighing 12-15 lbs and their male counterparts between 18-22 lbs.

With such a large conformation comes some health problems as well as particular orthopedic issues.

Types Of Patella Luxation In Maine Coons

There are two types of patella luxation based on the direction or side to which the patella has dislocated:

1. Medial Patellar Luxation (MPL)

If the patella has dislocated towards the inner side of the knee or toward the body then this condition is known as medial patellar luxation (MPL).

Medial patellar luxation occurs more frequently than lateral patellar luxation.

2. Lateral Patellar Luxation

If the patella gets dislocated towards the outside of the knee or away from the body then this condition is termed lateral patellar luxation.

This is less common than MPL.

Grades Of Patella Luxation In Maine Coons

The severity of the patellar luxation in Maine Coons can be determined by different grades of luxation.

In total, there are four grades of patellar luxation in cats, as follows:

1. Grade I

During Grade I, the patella or kneecap is slightly loose.

It moves normally within the trochlear groove the majority of the time but with slight manipulation or pressure, it can get dislocated out of the groove.

As soon as pressure is removed the patella will move back to its normal position.

Usually, there are no signs of pain or discomfort associated with grade I patellar luxation in Maine Coons. 

2. Grade II

During Grade II, the patella will dislocate in and out of the groove on its own quite frequently.

Sometimes the patella will not go back into the groove until the cat’s leg is fully extended or rotated in a way that allows the patella to move to its normal location inside the groove.

Most cats can move the patella back into its normal position by stretching and twisting their paws.

There can be signs of pain or discomfort associated with grade II in cats.

3. Grade III

During Grade III, the patella stays out of the groove the majority of the time. The patella can be moved to its normal position by applying manual digital pressure. 

However, when the pressure is released and there is slight movement in the joint, the patella or kneecap will pop out of the groove again.

Along with signs of pain and discomfort grade III patella dislocation can be accompanied by lameness.

4. Grade IV

During Grade IV, the patella always stays out of the groove and cannot be pushed back to its normal location manually even by applying pressure.

Generally, grade IV luxation is associated with congenital defects such as:

• Absence of the trochlear groove
• Wrong adhesion of the quadriceps on the tibia
• Hyper-rotation of the lower leg

For grade IV patellar luxation surgery is the best possible treatment option.

Along with pain and discomfort, the cat may also exhibit persistent lameness in the affected leg along with changes in posture (source 1,2,3,4,5,6).

12 Symptoms Of Luxating Patella In Cats

Signs of patella luxation in cats can vary depending on the:

• Age
• Breed
• Health Status
• The severity of the condition

Some cats with a lower grade luxation ( I and II ) may not show any symptoms of the condition.

However, cats that suffer from high-grade patellar luxation will exhibit a variety of signs and symptoms, some of which are mentioned below (source 1,2,3,4):

1. Pain And Discomfort In Knee Joint

There are usually no signs of pain and discomfort associated with the grade I and II patella luxation in Maine Coons.

But as the age of the cat increases and the grade of luxation progresses towards III and IV, the cat will exhibit signs of pain and this can also be due to the development of arthritis in the affected joint.

These are the 9 Signs Of Maine Coon Arthritis.

Due to the constant movement of the knee cap (patella) in and out of the groove, cartilage of the joint gets damaged and arthritis develops leading to excruciating pain.

2. Stifle Or Knee Joint Locking

When the patella of a cat has dislocated, it can sometimes get trapped or stuck in the wrong position resulting in the locking of the stifle or knee joint.

In such a case, the cat’s leg will stay extended and it will not bend until the patella comes back in the trochlear groove.

The patella can sometimes return to its normal position on its own, but it may also require manual manipulation by a person and, in severe situations, surgery.

3. Difficulty Jumping And Climbing Objects

Patellar luxation can reduce the range of motion of the knee joint in cats hindering their ability to do the following, effectively:

• Jump
• Run
• Climb Objects

4. Skipping

A common sign that is associated with patellar luxation in cats is skipping.

Skipping refers to intermittent lameness when the cat will regularly skip a step while walking or running.

If your Maine Coon does this, you must see a vet asap.

5. Bunny Hopping

In severe cases, when patellar luxation is present in both limbs of a cat, it will simultaneously move both of its rear limbs at the same time while:

• Walking
• Running

This movement resembles a bunny hop and is a very serious sign. It is more common in dogs but can occur in cats as well.

6. Lameness

Lameness can be present in one or both rear limbs of a cat due to patellar luxation and is usually associated with grades III and IV.

Lameness due to patella dislocation can be either intermittent (occurring now and then) or persistent in Maine Coons.

7. Crouch Stance In Hind Limbs

Some cats with severe patella luxation will be unable to walk properly and their posture will be highly abnormal.

They will appear to be crouching on one or both of their rear legs.

8. Popping Or Clicking Sound

If you’re wondering, what does luxating patella look like, unfortunately there are not many physical or visible signs of a luxating patella.

Except for a movable bulge around the knee joint, which can be felt by an experienced medical specialist.

However, you can HEAR a luxating patella as the vet manipulates the knee joint of a cat or when a cat walks and the patella gets luxated you will hear a pop or click sound indicating dislocation.

9. Side Kicking

When the patella gets dislocated out of the groove most cats will start to sidekick in an attempt to hyper-extend their limb and slide back the patella to its normal spot.

If you observe your Maine Coon side kicking too often it can be a sign of patella luxation.

10. Swelling Around The Knee Joint

Dislocation of the patella in and out of the trochlear groove for long periods can result in the thickening of the tissue around the joint, resulting in swelling.

11. Holding One Leg In The Air

Most cats with patellar luxation will hold one of their rear legs in the air for some time and will be reluctant to put weight on it or walk on it.

12. Chewing Or Excessive Licking Around The Knee Joint

If the cat has developed arthritis in the knee joint or is in constant pain due to a luxating patella, it will constantly lick and bite the affected knee joint

What Causes Luxating Patella In Cats?

In general, luxating patella in cats occurs due to either trauma or congenital defects, and the following are the main causes of luxating patella in cats:

Shallow Trochelar Groove

The foremost reason for patellar luxation in cats is the shallow trochlear groove.

If you do not know, the trochlear groove is a depression present at the distal end of the femur bone in which the kneecap sits.

If this groove is shallow and not deep enough, during movement the patella will dislocate.

Absence Of Trochlear Groove

In rare cases due to congenital defects there might be no groove at the end of the femur or the whole trochlea might be absent or deformed resulting in patella luxation.

Bow-Legged Or Cow-Hocked Bones

The patella will luxate if the bones, particularly the long bones (such as the tibia or femur), are excessively curved.

Abnormal Tibial Tuberosity

The tibial tuberosity is of great orthopedic importance because it is the point where thigh muscles and several ligaments such as the patellar and crucial cruciate ligament attach.

If the tibial tuberosity is off-center this can lead to patellar luxation in cats.

Abnormal Ligaments

Any abnormalities in the ligaments can result in patellar luxation in cats, including:

• The patellar ligament (which connects the patella to the tibia)
• The cranial cruciate ligament (which connects the femur to the tibia)
• The ligaments overlying the patella are off-center

Quadriceps Abnormal Attachment

If the quadriceps are attached obliquely to the tibial tuberosity this can increase the chances of patellar dislocation in cats.

Trauma To The Ligaments, Tendons, Bone, Joint, Or Muscle

Blunt trauma or injury to the knee joint or surrounding muscles, ligaments, tendons, or bones can lead to patellar luxation in cats (source 1,2,3).

How Common Is Luxating Patella In Cats?

A study performed on pedigree cats in the Czech Republic in September 2021 revealed that 32.7% of the cats had patellar luxation.

Out of this 32.7% of cats, 91.4% had bilateral patellar luxation (in both hind limbs). This study also revealed that most of the cats had Grade I and II patellar luxation.

When it comes to types, Medial Patellar Luxation (MPL) is more common in cats than Lateral Patellar Luxation (LPL).

So considering the results of this study we can conclude that patellar luxation is a very prevalent and common condition in cats worldwide.

The cat breeds that are more predisposed to patella luxation are (sources 1,2):

• Maine Coons
• Devon Rex
• Abyssinians
• Domestic Shorthair Cats

How To Treat Luxating Patella In Cats?

The treatment options for luxating patella in cats vary and depend on the severity of the condition and several other factors.

Generally, there are two main treatment categories:

• Supportive
• Surgical

For low-grade luxation ( I and II ) supportive treatments are preferred and for high-grade luxation ( III and IV ) surgical options are preferred by veterinarians.

Is luxating patella curable in cats? Keep reading to find out!

Supportive Treatments

Supportive treatments provide temporary relief to the cat and are preferred for grade I and II patellar luxations.

These treatments do not permanently cure the condition and only reduce the intensity of pain and discomfort.

1. Medications and pain management

Veterinarians will often prescribe painkillers and anti-inflammation drugs to cats that show the following signs and symptoms of patella luxation:

• Pain
• Discomfort
• Intermittent Lameness
• Swelling In The Knee Joint

2. Bandaging or slings

Different types of bandages, slings, or harnesses can be used to restrict the movements of the affected knee joint and stop the patella from dislocating.

3. Rest and restricted playtime

Cats with patella luxation will need to be restricted to reduce stress on the patella.

Vets may recommend reducing the time and intensity of play and exercise for the cat.

The veterinarian will only allow certain exercises that put less strain on the knee joint for a Maine Coon with patellar luxation.

4. Changes in the diet

Most veterinarians will recommend a diet change for a Maine Coon suffering from patellar luxation to make the joints healthy and strong while also reducing the progress of arthritis.

Surgical Treatments

Surgical treatment methods are preferred for cats with Grades III and IV to prevent the problem from recurring.

Surgery also successfully reduces pain and discomfort while recovering joint stability.

Luxating patella surgery success rate is high if arthritis has not developed and the age of the cat is between 2 to 5 years.

Below are some common surgical techniques employed to treat patellar luxation in cats, including Maine Coons:

1. Block Recession

If the patellar luxation is occurring due to the shallow trochlear groove this surgical technique is used to correct the problem.

This surgical procedure, known medically as trochleoplasty, involves removing a block of cartilage and bone to deepen the trochlear groove and prevent the patella from sliding out in the future.

Bone and cartilage are cut with the help of osteotome.

2. Retinacular Release And Tightening

If the trochlear groove is normal and the patella dislocates due to loose joint tissue and ligaments, vets use this surgical technique.

It involves tightening the joint tissue and ligaments surrounding the patella so it cannot slide out of the groove and stays fixed with the help of sutures and wires.

3. Tibial Tuberosity Transposition

If the patella of a Maine Coon luxates due to the abnormal position of the tibial tuberosity, or if the attachment of the patellar ligament is not at the spot this surgical method is preferred.

This involves moving the attachment point of the patellar ligament either:

• Medically (towards the body)
• Laterally (away from the body)

On the tibial tuberosity to stabilize the patella so it does not luxate out of the groove (source 1,2,3).

How Much Does Luxating Patella Surgery Cost

Surgery to fix luxating patella in cats can be very costly.

The cost of surgery varies and depends on several factors, including:

• Location of the clinic
• Expertise level of the veterinarian
• Materials available at the clinic
• Tax laws in the area
• The severity of the condition
• Age of the pet
• Weight of the pet

In the USA and Canada, the cost of surgery for treating luxating patella in cats ranges from $1000 to $2000 (for one knee). The price can be even higher if cases are complex.

In Australia, surgery for Luxating patella in cats can cost you between $1,600 – $2,050. If the condition is severe and complex the price may go up.

In the UK, the cost of patellar luxation surgery for cats is between £950 – £1260. However, the price might vary depending on the location, tax laws, and condition of the cat (source 1,2,3).

How To Help A Cat With Luxating Patella?

Below are some of the ways to help a cat with luxating patella:

Weight Reduction

If your cat is obese you can apply weight reduction methods by changing its diet and providing regular exercise.

Less body weight will put less strain on the luxating patella certainly improving the knee joint health.

Physiotherapy

You can take your cat to a professional veterinary physiotherapist to help with the knee pain.

They may also move the patella to its normal location if it has popped out of place with manual manipulation.

Laser Therapy

If your cat has excessive joint pain and is unable to move or walk, laser therapy can be a good option for pain management and improving joint health.

Joint Supplements

Vets can prescribe joint supplements for cats suffering from patellar luxation, such as:

• Glucosamine
• Chondroitin
• Omega 3/6 fatty acids

These supplements will not only improve joint health and reduce the incidence of patellar luxation but will also slow down the progression of arthritis in the affected joint.  

Joint Care Diets

Switching to diets that have joint-friendly ingredients can be beneficial for some cats with patellar luxation.

However, always consult a veterinarian before switching the diet of your cat.

Pain Medications

If your cat remains in constant discomfort and agony due to a dislocated patella you can ask your vet to prescribe painkillers such as gabapentin.

Massage

Massage may not stop the patella from luxating but it will surely increase the blood supply to the affected joint decreasing pain and swelling.

Restricted Exercise

Reduce the intensity and time of exercise and playtime for your cat and do not engage in serious physical activities with your cat.

Restrict Indoors

If your Maine Coon has patellar luxation restrict it indoors and do not allow it to go outside for extended periods (source 1,2).

How Long Does Luxating Patella Take To Heal?

If a Maine Coon is suffering from Grade I or II patellar luxation, medication will not cure the problem. The issue will also reoccur if the medications are stopped.

However, if the veterinarian has performed surgery then you must be wondering what is the recovery time for luxating patella surgery.

Normally, when patellar luxation surgery is performed on a cat, it is discharged from the hospital on the very next day.

If the surgery was not a major one the cat may resume normal physical activities within 2 weeks. If it is major surgery, it can take up to 8 weeks for the cat to begin activity again.

Post-operative examinations are performed at 2, 6, and 12 weeks ensuring proper recovery and healing of the surgical site (source 1,2).

Conclusion

Maine Coon patella luxation is one of the most prevalent orthopedic issues.

It refers to a condition in which a small oval bone known as the patella present in the knee joint of the Maine Coon pops out of place and gets dislocated causing:

• Pain
• Discomfort
• Lameness
• Other problems

Patellar luxation can be divided into 4 grades depending on the severity of the condition.

Generally, there are two types of Patellar luxation in Maine Coons either Medical Patellar Luxation (MPL) or Lateral Patellar Luxation (LPL). MPL is the most common one Maine Coons suffer from.

Causes of patellar luxation in Maine Coons can be either traumatic or congenital.

Treatment options for patellar luxation in Maine Coons include supportive and surgical options.