Arthritis in Cats

What is Arthritis in Cats?

Arthritis (also called degenerative joint disease or osteoarthritis) is a chronic, painful, progressive condition involving the joints of cats. As in people, this is commonly associated with aging, and likely impacts between 70% and 90% of cats over 12 years old.

Arthritis usually takes years to develop, with many changes occurring in the joints. The cartilage that normally lines and cushions the joint breaks down, allowing bones to rub together abnormally. Nearby bone may splinter and form sharp, bony projections into the joint. These leads to swelling, inflammation, and pain in the joints.

Most affected joints include the spine, hip, knees, and elbows—although any joint can develop arthritis. It is a progressive disease, meaning it continues to worsen over time. Because these joint changes cause pain, cats can show decreased mobility and lameness when they have arthritis.

While there is no breed or sex predilection for arthritis in cats, it is typically viewed as an aging disease.

Symptoms of Arthritis in Cats

Some cats with arthritis may not show any obvious signs—they can be very good at hiding their pain! Some obvious signs of arthritis include limping, swollen joints, and muscle wasting.

However, cats may display arthritis differently, and make it difficult for owners to recognize. Some cats may become hesitant to jump or play like when they were younger. They may have decreased energy or agility falling when they attempt to jump up or down on surfaces.

It may be difficult for them to move their body without pain to groom, so cats may be more unkempt. Some pet parents note changes in posture, such as not sleeping or sitting normally. If arthritis causes pain when they use the litter box, they may associate the litter box as the cause of the pain and start eliminating outside it. It is important to note that these changes do not occur overnight and usually happen gradually.

Causes of Arthritis in Cats

Arthritis can occur without known reasons, although genetics may play a role. This type is most associated with aging. Arthritis can also occur after an injury to the joint. These injuries can be minor in nature, and could be caused by:

• Ligament injury (such as ACL tear)

• Immune-mediated diseases, such as immune-mediated non-erosive polyarthritis

• Tick-borne diseases, like Lyme disease

• Direct trauma (such as a car accidents or a fall)

• Infection

• Congenital defect

Arthritis progresses due to the nature of the joint itself. After an injury, the cartilage releases enzymes within the joint that cause further breakdown of the cartilage and collagen, resulting in more inflammation.

How Veterinarians Diagnose Arthritis in Cats

Veterinarians may suspect arthritis in cats based on their physical exam, but it requires further testing for a definitive diagnosis. However, some cats are stoic and asymptomatic. These cats are most often diagnosed with arthritis incidentally—after feeling abnormalities on an exam or during an X-ray.

During a physical exam, veterinarians may find the following in a cat with arthritis:

• Lameness

• Changes in gait, posture, or sitting position

• Difficulties sitting or getting up

• Swollen or thickened joints

• Crepitus, or clicks in joints when moving

• Pain on palpation of joints

• Decreased range of motion of joints

While a veterinarian may strongly suspect arthritis, they need further diagnostics to confirm. X-rays are the standard diagnostic test to easily view bones and joints for changes. X-ray abnormalities include:

• Joint distention

• Bony outgrowths

• Soft-tissue thickening

• Narrowed joint spaces

• Calcified free-floating bony lesions (called joint mice)

Veterinarians may suggest a trial of pain medications to determine the degree of pain.

Treatment of Arthritis in Cats

Arthritis is extremely common with our feline companions, but there are many options to help them feel better and remain active. With appropriate management, we can slow the progression and allow them to lead very full lives. A multi-modal approach typically works best — multiple therapies used together for a better outcome.

Obesity is one of the most concerning factors for arthritis. Overweight cats put more strain on their joints. Lowering the weight of a heavy cat with arthritis is the first step to take in easing the strain on their joints. Weight reduction diets can be started. Talk to your veterinarian to discuss the right food and caloric intake for your pet.

Other treatment options include medicines, supplements, therapies, and surgery. Here is an overview of treatment possibilities for arthritic cats:

Pain Medications:

• Non-steroidal anti-inflammatories (like meloxicam and Onsior) are great at relieving pain and inflammation. However, they can have a significant strain on internal organ function and can have restrictions on the length of treatment.

• Gabapentin is used for many purposes, and its pain-reliving properties make it a good option for painful, arthritic cats.

• Opioids can be used, but they require additional precautions and may cause sedation.

• Polysulfated glycosaminoglycan (Adequan): This is an injectable prescription medication that supports joint health by stopping destructive enzymes within the joint. This medication is not labeled for use in cats, so talk to your veterinarian about using it off-label.

• Amantadine may also provide pain relief in some cats.

• Frunevetmab (Solensia) is a newer drug using monoclonal antibodies developed specifically for cats with arthritis. There are few studies in cats, but may be a beneficial drug for this treatment.

Supplements:

• Glucosamine/chondroitin: over-the-counter supplement to support cartilage and bones. Use caution with brands – most veterinarians recommend Dasuquin or Cosequin because they have a strong history of safety and effectiveness.

• Omega-3 fatty acids may decrease the inflammation in joints.

• In recent years, CBD (cannabidiol, an active ingredient in cannabis) has received attention for its pain-relief qualities. However, there is limited data in pets to know the effectiveness of CBD and similar products. In addition, legal issues surrounding CBD make it difficult to acquire, prescribe, and obtain quality and safe products. Talk to your veterinarian about all pain management options before starting treatments.

Medical/Supportive Care:

• Laser therapy (also known as a cold laser) can dramatically decrease inflammation and pain. Laser treatment typically starts with multiple treatments within a week and then tapers to the lowest effective dose.

• Acupuncture may help in some cases, although not all cats are agreeable to the process.

• Stem cell therapy has shown promising work in dogs, horses, and humans, but requires more research in cats.

• Warm/cold compresses for temporary pain relief, increasing blood flow and decreasing inflammation.

• Physical therapy can help with weight loss and joint mobility.

• Surgery is not always the first step, but it may ease the pain from some forms of arthritis. It is important to note that most surgeries involving joints will not guarantee that arthritis will not return over time, but such a procedure may allow a better quality of life. Surgical options include joint fusions, joint replacement, and amputation.

Recovery and Management of Arthritis in Cats

Arthritis is not reversible, so cats will never fully recover. But treatments can slow its progression and lead to an increased quality of life. Many cats with arthritis show few clinical signs, so diligent monitoring is essential.

Unless a previous disease or trauma occurred, most cats with arthritis are over age 10 when diagnosed—although arthritis may have started years earlier. New studies show around 60% of cats 6 years old have signs of arthritis.

As your cat ages, you may notice decreased ability to jump, play, and groom. They may start using the bathroom outside the litter box due to pain. Without treatment, arthritis can progress to debilitating and painful diseases. Talk to your veterinarian about the appropriate steps to treat your cat with arthritis.

Prevention of Arthritis in Cats

Because obesity is linked to arthritis, it is best to keep your cat lean. If your cat is already overweight, institute a weight loss program, following your veterinarian’s advice. Ask about arthritis in cats and start using cartilage protectant medications and supplements early. By doing so, you protect the cartilage that is there before it is too late.