Understanding Cruciate Disease and TPLO Surgery in Dogs

What is Cruciate Disease?

Inside your dog’s knee is a ligament called the cranial cruciate ligament (CrCL) — similar to the ACL in humans. It helps keep the knee stable when your dog walks, runs, or jumps.

Over time, this ligament can weaken and tear — either partially or completely — leading to pain, limping, and difficulty using the leg. This is known as cranial cruciate ligament disease (CrCLD).

Why Do Dogs Get It?

Unlike in humans, where ACL injuries are often caused by sudden trauma (like a sports injury), in dogs it usually happens gradually. The ligament weakens over time due to factors like:

• Age and wear

• Obesity

• Poor physical condition

• Genetics

• Breed and body structure

Some breeds are more prone to it (e.g., Labradors, Rottweilers, Mastiffs), while others are less commonly affected.

Also, if a dog tears one cruciate ligament, there's a 40–60% chance the same thing will happen in the other leg eventually.

Common Signs Your Dog May Have Cruciate Disease

• Limping or favouring one back leg

• Trouble standing up or jumping

• Swollen or stiff knee

• Decreased activity

• Muscle loss in one leg

• Clicking or popping sounds from the knee

• Reluctance to play

If your dog is showing any of these signs, it's time for a vet visit.

How is It Diagnosed?

Your vet will look at your dog’s walk, check the leg by hand, and likely take X-rays. In some cases, the ligament is only partially torn, which can make diagnosis a bit trickier. Two common tests vets use are:

• The drawer test

• The tibial compression test

These check how loose the knee joint is.

Treatment Options for Cruciate Disease

There are surgical and non-surgical options, and the best choice depends on your dog’s age, size, activity level, and how unstable the knee is.

1. Surgical Options (Most Common)

Surgery is usually the most effective treatment — especially for large or active dogs — because it restores stability in the joint and helps reduce pain and long-term arthritis.

TPLO (Tibial Plateau Leveling Osteotomy)

This is one of the most common surgeries for cruciate tears. Here’s how it works:

• A curved cut is made in the shin bone (tibia).

• The top of the bone is rotated to change how the knee moves.

• A metal plate and screws are used to hold it in place while it heals.

This surgery doesn’t “fix” the ligament itself — instead, it changes the way the knee works so the ligament is no longer needed for stability.

Benefits of TPLO:

• Strong, reliable outcomes in large or athletic dogs

• Faster return to normal activity

• Less arthritis progression over time

Downsides:

• Involves cutting bone (requires healing time)

• Rare risk of complications (like implant issues)

Other Surgical Options:

• TTA (Tibial Tuberosity Advancement): Similar to TPLO, changes the knee's mechanics but uses a different technique.

• Suture-based techniques: A strong suture is placed around the knee to mimic the ligament. Usually used in small or older dogs. Lower cost, but not as durable for active pets.

2. Non-Surgical Management

Not all dogs are candidates for surgery. In these cases, treatment may include:

• Strict rest and reduced activity

• Anti-inflammatory medications

• Physical therapy

• Joint supplements (like glucosamine)

• Braces (though there’s limited proof they help dogs)

This approach is usually best for smaller, older dogs or when surgery isn’t possible due to medical or financial reasons. However, it doesn’t fix the instability in the knee, so arthritis may progress faster.

What to Expect After Surgery

Post-op care is just as important as the surgery itself. For the best results:

• Limit activity strictly as advised by your vet

• Use rehabilitation exercises to help your dog recover faster

• Follow all medication and check-up instructions

Most dogs recover very well from TPLO and return to near-normal function. Around 85–90% of dogs show significant improvement. However, ongoing arthritis care and maintaining a healthy weight are essential for long-term success.

Final Thoughts

Cruciate disease is common — but very treatable. With the right care and guidance, most dogs go on to live happy, active lives.

If you think your dog might have a knee injury, or you have questions about TPLO surgery, contact our team. We’re here to help your pet get back on their feet.