If your dog is favoring a hind limb, they may have a condition affecting their knee. Cranial cruciate ligament (CCL) injury is one of the most common causes of dogs’ hind limb lameness. Our Scripps Ranch Veterinary Hospital team is committed to getting your dog back on all four paws as soon as possible. Learn about this condition and the preferred treatment.

Normal dog knee anatomy

The knee joint connects the femur and the tibia. Numerous ligaments and tendons help connect the bones and stabilize the joint. Two cruciate ligaments cross inside the knee joint as part of the stabilization apparatus. The CCL runs from the back of the femur to attach to the front part of the tibia, and the caudal cruciate ligament runs from the front of the femur to attach to the back part of the tibia. The CCL’s primary function is to prevent the tibia from moving forward in relation to the femur. 

Cranial cruciate ligament injury in dogs

Different scenarios can cause CCL injury. Learn three common causes for this condition:

  • Trauma — Traumatic injury can occur when a dog missteps, tearing or rupturing the CCL. This occurs most commonly in young, large-breed dogs. Affected dogs typically are acutely lame.
  • Degeneration — More commonly, gradual joint degeneration causes CCL injury. Factors such as obesity, poor physical condition, and conformation contribute to the condition. Breeds at increased CCL risk include Labrador retrievers, golden retrievers, rottweilers, and Chesapeake Bay retrievers. These dogs can experience acute lameness or develop chronic onset. 
  • Luxating patella — While CCL injury is most common in large-breed dogs, small-breed dogs with luxating patellas can also experience these injuries. 

A dog who has a CCL injury in one knee frequently experiences a problem in the other knee. Partial CCL tearing that progresses to a full tear is a common occurrence. 

Cranial cruciate ligament injury signs in dogs

CCL injury causes many signs. If your dog has a CCL injury, their signs may include:

  • Favoring a hind limb
  • Difficulty rising from a resting position
  • Trouble jumping onto high surfaces
  • Decreased activity level
  • Stiffness, especially after resting
  • Swelling on the inside of the back limb
  • Muscle atrophy on the affected side

Cranial cruciate ligament injury diagnosis in dogs

If our Scripps Ranch Veterinary Hospital team members suspect your dog has a CCL injury, they will perform a complete examination. CCL injury diagnosis involves the following:

  • History — Our team takes a thorough history about when your dog’s signs began and if they have improved or worsened since the issue first started.
  • Gait observation — We watch your dog walk, sit, and rise from a sitting position.
  • Palpation — We palpate your dog’s limb, checking for pain, range of motion, and swelling. 
  • Drawer sign — If the CCL is completely ruptured, a dog’s tibia will move forward in relation to the femur, exhibiting the drawer sign. Your dog may need sedation for this examination.
  • X-rays — X-rays allow our team to visualize joint effusion, rule out other issues, determine if arthritis is present, and take measurements for surgical planning.

Cranial cruciate ligament injury repercussions for dogs

When the CCL is injured, a dog’s knee joint is unstable. This results in significant pathologic changes for the joint, including:

  • Meniscal injury — The lateral and medial menisci are spongy, fibrocartilaginous structures made of collagen that sit between the femur and tibia. When the CCL is injured, the tibia is displaced, allowing the femur to damage the medial meniscus. 
  • Arthritis — The joint instability causes constant friction that results in degenerative changes, leading to chronic joint pain and joint function loss.

Cranial cruciate ligament injury treatment for dogs

The treatment of choice for CCL injury in most dogs is tibial plateau leveling osteotomy (TPLO). This procedure has the lowest reported postoperative meniscal tear rate and stabilizes the joint better to help slow arthritis development. Before surgery, our team X-rays the dog’s knee and measures the angle at the top of the shin bone (i.e., tibial plateau angle). The goal is to reduce this angle so that the tibia can’t move forward in relation to the femur. This is accomplished by cutting the top of the tibia and rotating the bone to create the desired tibial plateau angle. We then use a stainless steel plate to hold the bone in the new alignment. During the procedure, our team also evaluates your dog’s meniscus and repairs any of the structure’s damage. After surgery, our team X-rays your dog’s knee to evaluate joint function and help guide postoperative care. 

Tibial plateau leveling osteotomy postoperative care for dogs

Each dog is unique, and we base your dog’s TPLO aftercare on the work we have performed. Postoperative care is important to ensure successful healing. After surgery, your dog’s care strategy may include:

  • Exercise restriction — Your dog’s activity will be restricted for about 8 to 12 weeks. Jumping or running too soon after surgery can delay healing and damage their joint.
  • Weight management — If your dog is overweight, we devise a weight-loss strategy to help them safely lose the excess pounds.
  • Rehabilitation — Rehabilitation exercises help strengthen your dog’s muscles and improve their joint range of motion.
  • Joint supplements — We may recommend joint supplements such as glucosamine, chondroitin, and omega-3 fatty acids.
  • Monitoring — Follow-up X-rays at various stages are necessary to assess your dog’s healing process. 

Our Scripps Ranch Veterinary Hospital team is experienced in the TPLO procedure. Contact us if your dog has a hind limb lameness, and we will provide them with the best possible care.