By: Samantha Thomas DVM Candidate
In our companion animals, dogs are generally the first to come to mind when we think about orthopedic diseases. Because of their lifestyle of running, playing, swimming, and more, dogs are well acquainted with a variety of musculoskeletal injuries. But what about cats? Like dogs and people, cats can also develop a variety of orthopedic conditions that impact the musculoskeletal system. Unlike dogs however, discomfort related to these conditions often goes unnoticed as cats exhibit very subtle behavior changes and symptoms. Below we will dive further into the diagnosis and treatment for common feline orthopedic conditions.
Is your cat painful?
Historically, cats tend to exhibit signs of pain in very subtle ways. A cat experiencing discomfort from any cause can range from decreased interest in play to non-weight bearing lameness. Below are a list of clinical symptoms and behaviors that can be associated with pain.
- Anti-social behavior changes such as hiding
- Decreased interest in play and exploration
- Yowling or vocalizing
- Decreased appetite or thirst
- Reduced grooming
- Overgrooming
- Differences in litter box habits such a going outside of the box
- Aggression
- Gait abnormalities
- Tensed facial expressions
Zoetis has developed a great checklist for interpreting your cat’s mobility and signs of orthopedic pain. On the checklist there are videos to show the difference between normal cats and cats experiencing joint disease. Check out the interactive checklist here. In addition, to assess for pain, one can utilize the Feline Grimace Scale. The feline grimace scale utilizes ear position, squinting of the eyes, muzzle tension, whisker position, and head position to assess the degree of pain a cat may be experiencing. Click here to learn more about using the feline grimace scale to detect signs of pain.
What now?
If you believe that your feline friend is painful, the next step is to have them evaluated by a veterinarian. Your vet will first ask you a variety of questions to achieve a thorough history. This may include questions about your cat’s lifestyle, household, indoor/outdoor status, activity levels, bathroom habits, co-existing diseases and more. Next the cat will be allowed to walk around the room to assess his gait and mobility. Bringing a video from home is an excellent way to show mobility, habits and clinical signs, increased adrenaline when they are outside of their usual environment at the vet hospital may make pain even more difficult to interpret. A thorough physical and musculoskeletal exam will help the veterinarian to further localize the region of interest. Each limb will be thoroughly assessed for full range of motion, decreased movement, swelling, pain response, instability, or crepitus.
Diagnostics?
Once a painful limb is identified, additional diagnostics can be performed if indicated. Radiographs of the affected area are generally the first diagnostic tool utilized. Radiographs can assess for evidence of joint swelling, boney proliferations, wearing away of the bones, and fractures. For more complex conditions more advanced imaging may be warranted to come to a complete diagnosis.
So what are some common feline orthopedic conditions and how do you treat them?
Osteoarthritis (OA)
Osteoarthritis in cats is a degenerative condition in the joints where the normal cartilage breaks down over time. With continued degeneration, the bones adjacent to the joint start to rub against each other. This motion leads to pain, decreased mobility of the joint, and potentially boney proliferations such as a bone spurs. OA can be the result of a previous traumatic injury such as a cruciate ligament injury, but is usually associated with age related changes. Although this condition cannot be cured, treatment is targeted toward pain control.
Treatment for OA is generally conservative. Getting your cat to an appropriate weight for his frame is the most beneficial aspect in preventing further damage associated with OA. A consultation with your vet can help determine the appropriate amount of calories that he should eat in a day. Making changes to your cats home environment is another important modification. Treatment with non-steroidal anti-inflammatory medications (NSAIDs) has been shown to be a very effective analgesic for OA cats. NSAIDs work to decrease the amount of inflammation associated with the existing joint disease. A cat placed on NSAID therapy, should be monitored routinely to ensure efficacy of treatment as well as safety.
Another newer option for felines with osteoarthritis is to place them on monthly Solensia injections. Solensia is a monoclonal antibody that works by controlling nerve growth factor for pain control. This works to limit inflammation, control pain, and improve mobility within the joint. Many owners begin to see improvement in their cats clinical symptoms as within the first week, but it can take 3-6 months to see the full effect of the medication. We are happy to discuss Solensia with you at Dogwood Veterinary Clinic and how we can make the pets of Louisville, KY more comfortable.
Cranial Cruciate Ligament Disease
Like dogs, cats can suffer from cranial cruciate ligament (CCL) disease. The CCL is a ligament within the knee that, when intact, prevents the lower leg (tibia) from moving forward when the cat walks. Like dogs, CCL disease is a degenerative process that can be exacerbated with trauma. A tear can be partial, meaning there is a portion of the ligament remaining intact, or complete.
Treatment for CCL disease is generally conservative in cats, but there are surgical options for cases that do not resolve with conservative management. Treatment with NSAIDS as well as Gabapentin are generally the mainstay in therapy for these patients. Although difficult, attempts should be made to limit activity such as jumping or climbing while in recovery (But, cats will be cats!). Over time, the torn ligament will begin to scar over and the inflammation will subside. These cats can return to normal mobility with conservative therapy. In severe cases, procedures such as a the lateral suture, MMP and TPLO have proven to be effective corrective surgical procedures.
Immune Mediated Polyarthritis
Immune Mediate Polyarthritis (aka IMPA) is a condition where the antibodies of the cat’s immune system begin to inappropriately attack the articular cartilage of the joint spaces. This leads to a significant amount of inflammation throughout multiple joints in the body. This condition impacts overall joint function as well as the cat’s mobility. IMPA can be the result of multiple causes such as viral infections, bacterial infections, hypersensitivity to certain medications, gastrointestinal disease, cancer, heartworms and more. A more frustrating feature of this disease is that oftentimes, IMPA has no link to an identifiable cause. Symptoms include swelling of multiple joints throughout the body, lethargy, difficulty walking or stiffness, crepitus or cracking of the joints upon movement, and a low grade fever.
Diagnosis of IMPA is very different than most orthopedic diseases. Because IMPA can be the result of multiple disease processes, baseline bloodwork and urine analysis are commonly used as a rule out for many systemic causes. Radiographs of the affected joints show fluid within the joint spaces, soft tissue swelling, and in some severe cases erosive changes to the adjacent bones. A sample of joint fluid is also drawn for analysis.
Treatment for IMPA varies based on the underlying cause. If an infection is at play, treatment with an antibiotic, antifungal or antiviral may be warranted. For cases with no identifiable causes, medications to suppress the immune system in combination with anti-inflammatory medications and analgesics are used. Cats with severe infections of the joint spaces may require surgical removal of the infected tissue. It should be noted that IMPA may require lifelong treatment and recurrence may be possible throughout the animal’s lifetime. A thorough workup by your veterinarian is required to develop the most appropriate treatment for your pet.
Hip Dysplasia
Like certain purebred dogs such as the Labrador and Rottweiler, cats too can have a genetic predisposition to hip dysplasia. Hip dysplasia is a genetic developmental condition leading to a malalignment of the hip joint. At birth affected cats tend to have a normal conformation in their hip joints. Over time, the hips become increasingly lax and create a degree of separation between the ball and socket joint of the hip. This can lead to joint pain and inflammation during movement. In some cases, the degree of joint laxity can be so severe that subluxation of the femur out of the hip joint is possible. Over time, evidence of boney change consistent with osteoarthritis will be apparent with the joint spaces. This condition is bilateral and will eventually impact both hip joints over time. The Maine Coon and Siamese are two of the more commonly affected breeds to experience hip dysplasia. Clinical signs can be relatively non-specific and can include lameness, reluctance to jump or climb, and many of the symptoms related to pain described above. To diagnose hip dysplasia, radiographs of the pelvis are required.
Treatment for feline hip dysplasia is relatively conservative. A key component to therapy is maintaining an appropriate healthy weight. Obese cats with hip dysplasia tend to experience more pain as well as osteoarthritic changes compared to cats with healthy body conditions. Medical management of this condition is similar to that of osteoarthritis. A combination of anti-inflammatories and other analgesics are recommended daily for continued pain control. In severe cases, surgical options such as a femoral head osteotomy or total hip replacement may be effective options.
Fractures
Have you ever heard the phrase “curiosity killed the cat”? Well let’s face it, countless injuries that cats experience result from them doing things or getting into things that they should not have. Like dogs and people, cats can experience a variety of fractures secondary to trauma. Fractures can be seen on the antebrachium, humerus, femur, tibia, carpus, and tarsus just to name a few. After obtaining an accurate history and localizing the pain to a specific area, radiographs are performed to come to a diagnosis. If a cat sustained a big trauma, additional radiographs of the chest and abdomen are usually recommended to ensure the remainder of the internal organs and other boney structures are intact.
Based on the type of fracture and location, a variety of treatment options can be used. Splinting the affected limb, placing an intramedullary pin, utilizing internal fixators, bone plating a limb, and utilizing screws and cerclage wires are just a few options commonly used to stabilize fractures. If surgery is selected and implants are used to stabilize the fracture, radiographs are used to confirm appropriate location of the equipment and reduction of the fracture ends. Keeping the patient comfortable with analgesics and rest is critical for healing.
Hopefully this information provided some knowledge about common feline orthopedic diseases. We understand that your cats are not only pets, but part of your family. If you suspect that your pet may be experiencing orthopedic pain, we are happy to examine them and discuss options with you. It is important to us at Dogwood Veterinary Clinic to work with the veterinary patients of Louisville, KY to keep them as comfortable as possible.