Feline Osteochondrodysplasia: Symptoms, Diagnosis, and Treatment Explained in Detail by a Veterinarian

Osteochondrodysplasia is a hereditary joint disease primarily affecting Scottish Folds. In severe cases, joints can swell up like lumps, making it difficult to walk and causing pain.

This article explains in detail the symptoms, diagnosis, and treatment of osteochondrodysplasia in cats.

What is Osteochondrodysplasia?

Osteochondrodysplasia is a hereditary joint disease that causes abnormal gait, pain, and joint deformities.

About Osteochondrodysplasia

Osteochondrodysplasia is a disease in cats where abnormalities occur in the cartilage and bones. Cats with osteochondrodysplasia experience abnormal cartilage in their joints, causing the joints to swell like lumps (bone exostosis), leading to difficulty walking and pain. In addition to bone exostosis, tail deformities can also occur. This disease is progressive, and bone exostosis and deformities gradually worsen with growth.

Genetic Factors and Risk of Development

Osteochondrodysplasia is caused by a genetic abnormality. The cat breed most susceptible to this disease is the Scottish Fold, and its distinctive folded ears are linked to osteochondrodysplasia.

Let's explain genetics. Parents typically have two genes that form a pair, but in sperm and egg cells, they separate into individual genes, which then pair with the partner's genes during fertilization.

Folded ears are a "dominant trait," meaning that even if only one abnormal gene is present in the parent, it will manifest. If a parent cat has folded ears, all their kittens will have folded ears. Since osteochondrodysplasia causes cartilage abnormalities, Scottish Folds with folded ears are likely to suffer from osteochondrodysplasia, although the severity of symptoms may vary.

Especially when two folded-ear cats are bred, the resulting kittens tend to have more severe joint abnormalities. Scottish Folds without folded ears are less likely to develop osteochondrodysplasia, or if they do, the symptoms tend to be milder.

As it is a hereditary disease, it manifests at a young age and gradually progresses.

While Scottish Folds are particularly well-known, American Curls, Himalayans, Persians, and Munchkins are also said to be susceptible.

Symptoms and Diagnosis of Osteochondrodysplasia

Symptoms of Osteochondrodysplasia

A characteristic symptom of osteochondrodysplasia is the formation of bone exostosis, or lumps, in the wrist and ankle joints. This fixes the joints, leading to a clumsy gait. Bone exostosis can be felt by touch. In addition to hand and foot joints, tail deformities can occur, but other joints like the elbow, shoulder, knee, and hip are not affected.

Symptoms include a clumsy gait or dragging of the feet. If the bone exostosis is large, a clicking sound may be heard during walking. Osteochondrodysplasia is accompanied by pain, so cats may become reluctant to move, avoid jumping, and become less active. They may also strongly resist nail trims.

The sitting posture seen in Scottish Folds, where they stretch their hind legs forward, is sometimes called "Scottish sit," and is thought to be a way to avoid putting pressure on deformed ankles.

Diagnosis Method

At the veterinary hospital, the diagnosis process typically begins with a consultation, visual examination, and palpation in the examination room. This is followed by X-rays of the paws, feet, and tail for definitive diagnosis.

X-ray images of cats with osteochondrodysplasia show characteristic bone exostosis and joint deformities in the paws and feet.

Since cats may become inactive in the examination room, it is helpful for diagnosis if you can provide videos of their walking and jumping habits at home.

Treatment and Care for Osteochondrodysplasia

Osteochondrodysplasia is a hereditary disease, and there is currently no known cure in modern veterinary medicine. Therefore, pain control is the primary treatment method.

Anti-inflammatory Painkillers and Supplements

Since osteochondrodysplasia involves the progressive deformation of cartilage and joints, there is no radical cure. Symptomatic treatment primarily focuses on pain control. This involves managing pain with anti-inflammatory drugs and using supplements to protect joints and reduce pain. Most treatments are oral medications, but injectable medications for arthritis may also be used.

Radiation Therapy

In severe cases where large osteomas have formed, radiation therapy is said to show improvement. Facilities capable of performing radiation therapy are limited to specialized hospitals, such as university hospitals, referred to as secondary referral facilities, and the procedure is performed under general anesthesia. Therefore, treatment costs are high.

Surgery

Arthritis can cause the formation of bone spurs, which are sharp bony outgrowths, leading to severe pain. Surgical removal of these bone spurs may be performed, but the purpose is to provide temporary symptom relief.

Care for Osteochondrodysplasia

When a cat develops osteochondrodysplasia, not only does it become difficult for them to walk or jump, but they also suffer from pain. Therefore, early detection and early treatment are crucial to improve their quality of life.

At home, to reduce strain on their joints, it's a good idea to install ramps in areas with steps. As it becomes difficult for them to navigate high-sided litter boxes, switching to a litter box with lower sides is also important. Place water and food bowls within your cat's comfortable range of movement.

Increased weight puts greater stress on the joints. Therefore, it is important to control food intake to avoid overfeeding.

Tips for Early Detection

As osteochondrodysplasia is a hereditary disease, there is no prevention method. Currently, Scottish Folds are advised not to be bred if both parents have folded ears, but any folded-ear Scottish Fold has a high probability of developing the condition. It is important to keep in mind that susceptible breeds such as Scottish Folds, Munchkins, Persians, and Chinchillas may develop osteochondrodysplasia.

Since there is no cure for osteochondrodysplasia, the main treatment focuses on controlling pain once symptoms appear. By the time symptoms are noticeable, the pain may already be severe, so early detection and prompt pain relief can significantly improve the cat's quality of life.

To achieve this, it's important to take your cat to the vet regularly from kittenhood, having their weight checked and joint movement examined. Additionally, getting X-rays of their paw and leg joints after one year of age is crucial for diagnosing any joint abnormalities at the earliest possible stage.

Summary

Osteochondrodysplasia is a hereditary disease with no known prevention or cure. It causes pain and difficulty in movement, which can be very stressful for cats. If you own a susceptible breed like a Scottish Fold, regular veterinary check-ups are essential to alleviate their pain as early as possible.