Cranial cruciate ligament rupture

Cranial cruciate ligament rupture is one of the most common orthopaedic conditions seen in dogs.
The cruciate ligaments are located inside your dog’s stifles. They attach the femur to the tibia providing crucial stability to the joint. A partial or complete rupture of those ligaments is a serious and painful injury that can affect any dog or cat.

Causes

Cruciate ligament rupture can be acute or chronic. The acute injury is usually traumatic in origin and is most commonly associated with hyperextension and internal rotation of the leg. This can happen very quickly when the dog is running, playing, jumping, sliding on slippery floors or breaking suddenly. Chronic injury is usually the result of age related deterioration, obesity, conformation abnormalities or immune mediated diseases. In most cases many factors are involved.

Cruciate ligament disease can affect any dog or cat although younger, active large breed dogs seem to be at high risk. Breeds often affected by the condition include Rottweilers, Labradors and Golden Retrievers, but can happen in our cross breeds too!

Signs and symptoms

Signs and symptoms can vary greatly from a subtle chronic lameness to an acute non-weight bearing lameness where the dog is unable to put the affected leg down. The condition is painful and some dogs are also shaking, whimpering, depressed and have a loss of appetite.

Examination                                                                  

In most cases the orthopaedic examination will reveal a swollen knee with pain when the joint is flexed or extended. Most importantly, if the animal is relaxed enough an instability can be detected. This is called a positive cranial drawer movement and is diagnostic of the disease. In chronic cases it is also possible to feel some fibrosis, muscle atrophy, crepitus and reduced range of movement.

Radiographs                                                                  

Radiographs under general anaesthesia are usually taken to confirm the diagnosis and to rule out other conditions such as fractures, luxations, infection or cancer. Although the ligaments are not seen on the radiographs we typically observe joint effusion and early signs of arthritis.

Complications

Cruciate ligament disease if left untreated can lead to chronic pain and lameness, arthritis, meniscal injury, loss of movement, muscle atrophy, loss of athletic ability and loss of limb function. It is a serious debilitating disease and needs to be treated with care and attention.

Treatment

Surgical intervention remains the best option for your dog’s return to a good function and quality of life. Many surgeries are possible but the most popular ones are:

1-Extracapsular Repair

A strong synthetic suture material is placed outside the joint in a way to act like an artificial ligament. This usually works well in smaller dogs.

2-Tibial Plateau Leveling Osteotomy

The aim of this technique is to reduce the slope at the level of the tibia which results in forces that stabilise the knee. It is the technique of choice for larger dogs.

Regardless of the technique chosen the joint is always inspected carefully for any signs of meniscal damage.

Conservative medical treatment

Conservative treatment entails REST, non steroidal anti-inflammatory medication (pain relief) and a course of cartrophen injections. The recovery period is approximately 6-8 weeks. Once the majority of the pain and inflammation are resolved, a conservative regime of exercise and weight loss (if necessary) should be initiated. Conservative therapy is best tolerated in patients weighing less than 10 Kg. Results are more unpredictable in larger animals. Given enough time, the lameness and pain often resolves with small patients and they appear to function fairly normally. However the instability persists and secondary degenerative joint disease inevitably develops leading to irreversible damage and chronic pain.

Post Surgical Complications

Post surgical complications are considered rare but include implant breakdown, infection, wound healing problems, bandaging problems and failure to return to normal function. It is also important to remember that 40-60 % of dogs will experience cruciate ligament disease in the other leg within one or two years.

Aftercare

After care mainly consists of strict rest for a period of 6-8 weeks. The animal needs to be kept in a confined area and is aloud to go out on a lead for toilet needs only. A bandage is usually applied to the leg for a period of 3-5 days. Usual wound care also applies to the surgical incision. Depending on the repair technique, radiographs are recommended after 6 weeks to assess the healing process. After that period supervised exercise is slowly introduced and physiotherapy can be instituted if needed.

If your pet is suffering from cranial cruciate ligament disease do not hesitate to contact our team at King Street Veterinary Hospital. We will help you make the best decision for your dog and will address any of your concerns. Our priority is to keep you and your pet happy for a long time !