The cranial cruciate ligament (CCL) is one of the most important ligaments inside of the canine stifle (knee) and is critical in providing stabilization of the joint. Damage or rupture of this ligament is the most common reason for hind lameness and pain.
The most common cause of injury to the CCL is a combination of multiple factors including aging, obesity, poor physical condition, genetic pre-disposition and breed. The majority of the time with the ligament ruptures it is the result of changes and degeneration over time, rather than an acute trauma to a healthy ligament (rare occurrence). It is important to note that partial tearing of the CCL is common in dogs and progresses to full or complete tear over time, as well as 40 to 60% of dogs that develop cruciate disease or rupture will at some point develop a similar problem in the other stifle.
Cruciate disease can affect dogs of all sizes, breed and ages; however, some large breeds such as the Rottweiler, Newfoundland, Mastiff, Akita, Saint Bernard, Labrador Retriever, Staffordshire Terrier, and Chesapeake Bay Retriever have a higher rate of occurrence.
Clinical signs of CCL injury include difficulty rising from sitting, difficulty jumping, lameness, decreased range of motion, stifle swelling, pain, stiffness and/or muscle atrophy (decreased muscle mass).
Diagnosis of CCL injury is based on physical examination findings and radiographs.
There are many options for treatment of CCL injury, and vary depending on severity and size of your pet. Osteotomy-based techniques require cutting the bone which changes the way the quadriceps muscles act on the top of the shin bone. Stability of the knee joint is achieved without replacing the CCL, but by changing the biomechanics of the knee joint. This can be accomplished by either advancing the attachment of the muscle (Tibial Tuberosity Advancement (TTA)) or by rotating the plateau (slope) of the shin bone (Tibial Plateau Leveling Osteotomy (TPLO)). The advantages of osteotomy-based procedures include better outcomes in larger dogs compared to suture-based techniques with more mobility and less development of arthritis. The disadvantage would be the need to perform an osteotomy and require healing of the bone. Fortunately complications are rare, especially when performed by an experienced board-certified surgeon.
Suture based techniques can be performed either intra-articular (inside the joint) or extra-articular (outside the joint), with the majority of these techniques being performed extra-articular. The most commonly performed technique is called extra-capsular suture stabilization, which utilizes suture placed just on the outside of the stifle joint (but under the skin) to mimic the stability offered by the CCL. A variation of this technique is called Tightrope® and allows the surgeons to use bone tunnels for proper suture placement. The main advantages of these procedures are lack of an osteotomy (cutting the bone) and lower costs than a TPLO or TTA. The disadvantages would include breakdown or failure of the suture and progressive arthritis.
Non-surgical treatment would involve a combination of pain medications, exercise restriction or modification and physical rehabilitation.
It is important before making any decision that you discuss with your regular veterinarian and/or surgeon treatment options and your pet’s individual life-style and needs to determine the best course of action to achieve the best outcome.