Osteochondrosis in Cats: A Hidden Cause of Stifle Lameness

When it comes to feline orthopedic conditions, stifle lameness is often a sign of something more serious. While it might be easy to overlook, one potential culprit that veterinarians should be aware of is osteochondrosis (OC) or osteochondritis dissecans (OCD). These conditions, which are often associated with the knee joint in dogs, have been increasingly identified in cats as well. A new case series and literature review sheds light on this often-overlooked condition in cats, helping veterinary professionals recognize and treat stifle lameness in their feline patients.

A Closer Look at Osteochondrosis in Cats

Osteochondrosis in cats, particularly affecting the stifle (knee) joint, is rare but serious. A recent study reviewed the cases of six new cats diagnosed with stifle osteochondrosis, bringing the total number of documented cases to 10. This study is groundbreaking because, prior to this, there were only four single case reports in the veterinary literature. These findings provide a much-needed look into the presentation, treatment, and prognosis of this condition in cats.

The condition is most commonly seen in young cats, with the average age at presentation being just 10.5 months. This points to a potential developmental issue, as osteochondrosis typically affects rapidly growing bones. Interestingly, of the 10 cats in the study, the majority (seven) were male, with six of those cats being castrated. The other three cats were female and spayed. In terms of breed, domestic shorthairs were the most affected, though Maine Coons, Bengals, Devon Rex, and Scottish Folds also showed signs of the condition.

The Symptoms: What Should Veterinarians Be Looking For?

Cats with osteochondrosis in the stifle joint typically present with lameness, stiffness, and difficulty jumping. A telltale sign often includes stifle joint effusions, or swelling in the knee area. The condition can be unilateral or bilateral. In the study, seven of the cats had the condition in only one knee, while three had it in both. Interestingly, the cats with bilateral lesions all had osteochondrosis in the lateral aspect of the femoral condyle, while those with unilateral lesions often had damage to the medial femoral condyle.

In two of the cats with lesions on the medial femoral condyle, there was also concurrent patellar luxation, which occurs when the kneecap moves out of its normal position, further complicating the diagnosis and treatment plan.

Diagnosis and Treatment Options

For veterinarians, recognizing osteochondrosis in cats can be challenging, but it should always be considered as a differential diagnosis in cats presenting with stifle lameness or joint effusions, especially in younger patients. The condition is particularly notable in immature cats that are still growing, making it crucial for vets to catch it early to prevent long-term joint damage.

Once diagnosed, there are a couple of different approaches to treatment. The most effective method for treating osteochondrosis in cats is surgical debridement of the osteochondritis dissecans (OCD) lesion. In the study, six of the cats who underwent this surgery showed significant improvement or complete resolution of lameness. For cats where surgery isn’t an option or for those with less severe cases, conservative management, including rest and anti-inflammatory medications, was successful in two of the cases.

Follow-up care is crucial, with the study reporting a minimum of four weeks of observation after treatment. In all the cats who received follow-up, their lameness resolved or improved significantly, highlighting the importance of early intervention.

What Does This Mean for Your Feline Patients?

As veterinarians, it’s important to keep osteochondrosis in mind when diagnosing stifle lameness, especially in young, growing cats. While this condition is still rare, the increasing number of documented cases suggests that it may be more common than previously thought. By recognizing the symptoms and diagnosing it early, veterinarians can provide appropriate treatment, which can lead to better outcomes for these affected cats.

This study highlights the importance of considering developmental orthopedic conditions like osteochondrosis when faced with a feline patient presenting with unexplained lameness. In many cases, the condition can be effectively managed with either surgery or conservative treatment, allowing cats to regain full mobility and continue enjoying an active, healthy life.

Veterinarians should also be aware that patellar luxation may often be a concurrent diagnosis, adding an additional layer of complexity to the treatment plan. With this new insight into the diagnosis and treatment of stifle osteochondrosis, vets can better address this challenging condition and improve the lives of their feline patients.

Read full article here: Osteochondrosis in the feline stifle: a case series and literature review