What is it?
• The cranial cruciate ligament (CCL) is the main structure that stabilizes the knee joint
• CCL disease results when the CCL itself begins to degenerate, causing a chronic condition leading to pain and instability
• This may eventually cause the ligament to rupture, or tear, which increases the amount of pain and instability in the joint

What causes it?
• CCL disease usually occurs in one knee initially, but a rupture in the other leg is common within 6-12 months
• It most commonly affects middle-aged and older dogs, although sometimes occurs in younger dogs and occasionally cats
• The actual cause of CCL disease is debated
• It is thought that the shape of the tibia (the large bone just below the knee) may have a role in this condition in combination with other factors
• In many cases, the onset of clinical signs will only result after the rupture
• Typical symptoms of arthritis such as lameness are seen and worsen with time

What tests are needed?
• Orthopedic examination will determine the degree of stiffness, fluid, and pain in the joint
• X-rays may reveal signs of osteoarthritis and misalignment of the bones involved with the CCL
• Sometimes diagnosis can only be made through arthroscopy, or the passing of a viewing scope into the knee

How is it treated?
• Medium and larger dogs typically improve with surgery, to facilitate the stability of the joint
• Smaller dogs and cats are typically treated with medical therapy
• However, there are several techniques for improving the stability of the knee overall, including various forms of surgery and physical therapy with restricted exercise

What follow up care is needed?
• Strict exercise restrictions must be implemented for at least 8-10 weeks after surgery
• The incision will be regularly checked for redness, discharge, or swelling
• Physical rehabilitation at home prior to recovery has often proved beneficial
• Dogs with a torn meniscus accompanied with CCL disease must be treated appropriately