Osteoarthritis (OA) is an important factor that affects quality of life in cats, with a reported prevalence of up to 92% in older cats.1 Clinical signs in cats can differ from other species; predominant signs may be related to behavior changes (eg, decreased willingness to jump, altered grooming behavior, aggression, urination outside the litter box) rather than lameness.1-3
OA can be diagnosed via orthopedic examination and radiography of the affected joint or joints. Following diagnosis, a multimodal treatment plan that is tailored to the patient and accounts for comorbidities can be instituted. This article presents common OA treatments for geriatric cats.
1. Pain Management
Pain management is integral to treatment of discomfort in patients with OA, and NSAIDs are the mainstay treatment in many species. In cats, meloxicam and robenacoxib are commonly administered and can improve clinical signs associated with OA; however, long-term use of NSAIDs (eg, meloxicam) in cats is extra-label in the United States.4-6 Concurrent health issues (eg, chronic kidney disease) can complicate NSAID use in older cats because of increased risk for adverse effects. If necessary, low doses of meloxicam (0.01-0.03 mg/kg PO every 24 hours) may be administered safely in older cats with chronic kidney disease.4 Prior to administering NSAIDs, pet owners should be educated on the risks and benefits, and cats should be well hydrated; owners should closely monitor for signs that may indicate progression of kidney disease.7 To minimize risk for adverse effects, NSAID doses should be based on lean body weight and tapered to the lowest effective dose by lowering the mg/kg of each dose, administering the medication less frequently (eg, every 2-3 days), or administering the medication only as needed. Routine laboratory testing (eg, CBC, serum chemistry profile, urinalysis) should be performed prior to initiation of therapy and at regular intervals (at least every 6 months but more frequently if problems are identified) during therapy.5,7,8
Tramadol, gabapentin, and frunevetmab (a feline antinerve growth factor monoclonal antibody) have been investigated as analgesics for cats with OA. Study results have shown tramadol (extra label in cats) can improve activity levels,9 gabapentin (extra label in cats) can increase some activities but results in a decrease in overall activity (likely due to sedative effects),10 and frunevetmab (FDA-approved for control of pain due to OA in cats) can provide benefits identified on owner questionnaires and veterinary assessments of joint pain.11 Frunevetmab appears to be well tolerated; however, cutaneous adverse effects (eg, pruritus, alopecia, ulcerations) have been observed in small numbers of patients, and further research is warranted to help understand the long-term effects and benefits of this medication.12
2. Environmental Modification
Because behavior changes are a primary clinical sign of OA in cats, altering the environment to facilitate access to resources (eg, food, water, a safe space) can improve quality of life. Potential modifications include provision of steps (Figure 1) and ramps to reach elevated safe spaces, padded and/or warm bedding (Figure 2), easily accessible food and water bowls, large and easily accessible (eg, lowered side) litter boxes, and environmental enrichment through toys and owner interactions.8
Steps leading to an elevated space
Padded bedding
3. Weight Management
Maintenance of a lean body weight is important for managing OA pain. Excess adipose tissue can contribute to inflammation in the body that may worsen OA.13-16 Increased body weight can also lead to chronic, repetitive overloading of joints that can exacerbate clinical signs.
Weight loss can be challenging, particularly for older indoor cats with low activity levels. Strategies include feeding meals in puzzle toys, feeding low-calorie diets, limiting treats, feeding animals in multipet households separately, and increasing activity.8,17
Talking About Weight Loss
Weight loss conversations can be uncomfortable, but weight loss can be essential for patient health. Try these tips for productive discussions about body weight.
Ask the client for permission to discuss weight. The conversation should feel like a collaboration, not an accusation.
Avoid judgmental or cutesy language. Rather than using terms like chonky or phrases like He’s been getting too much food or too many treats, focus on the issue at hand, which is that excess weight can be detrimental to health, and you’d like to discuss ways to help the patient stay healthy.
Resist the temptation to equate a pet’s weight challenges with human ones. Any human who has dieted knows weight loss can be frustrating and difficult. Focus on the patient and your sincere desire to work with the client as a team to keep their pet healthy.
Create a weight-inclusive environment so clients have no reason to feel self-conscious. Make sure chairs can accommodate a range of body sizes (eg, sturdy chairs without armrests) and posters and other materials in the hospital and examination room avoid judgmental language about weight.
4. Exercise Modification
Exercise can provide many benefits, including increased muscle mass, decreased body weight, maintenance of normal joint range of motion, and reduced boredom.16 Small animal rehabilitation specialists can provide activities to help decrease body weight, build muscle, and control pain in cats with agreeable temperaments. At-home exercises may be instituted if regular travel to the clinic is not possible. Routine play with an owner may also help increase activity level, encourage weight loss, and improve quality of life.
5. Joint Supplements
Supplements are commonly administered to veterinary patients with OA and may help increase joint comfort over time. In one study, cats given a 10-week course of supplemental omega-3 fatty acids had improved activity in the home, including elevated activity levels, higher jumps, and increased interactions with owners.18 In another study, cats given a diet high in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and supplemented with green-lipped mussel extract, glucosamine, and chondroitin had significantly increased activity levels compared with cats given a control diet.19 In contrast, one study found a small but not statistically significant improvement in mobility that was generally maintained after supplementation with glucosamine and chondroitin was discontinued.20
6. Surgery
Although evidence indicates primary OA is common in cats, some cases of OA may be due to treatable orthopedic conditions (eg, cranial cruciate ligament disease, hip luxation, fracture; Figure 3).2 Cats undergoing surgical treatment (eg, tibial plateau leveling osteotomy, tibial tuberosity advancement, extracapsular repair of cranial cruciate ligament tears, femoral head ostectomy, total hip replacement) for these conditions can have excellent outcomes and may have decreased OA development over time. Return to function may be faster if these conditions are addressed promptly.21-24
Bilateral hip luxation in a cat
Conclusion
OA is prevalent in older cats and can have a significant impact on mobility and quality of interactions with owners. Recognizing potential clinical signs and using multiple treatment strategies can improve long-term pain control, mobility, and quality of life.
Listen to the Podcast
Dr. Barnes imparts more of her wisdom for treatment and management of OA in cats in this episode of Clinician's Brief: The Podcast.