The most common knee injury in the dog is rupture of the Cranial Cruciate Ligament (CCL), also frequently referred to as the Anterior Cruciate Ligament (ACL). This injury can occur at any age and in any breed, but most frequently occurs in middle aged, overweight, medium to large breed dogs. This ligament frequently can suffer a partial tear, leading to slight instability of the knee. If this damage goes untreated, it most commonly leads to complete rupture and possibly damage to the medial meniscus of the knee. The meniscus acts as a cushion in the knee.
When the ACL is weakened or torn, the most significant long-term change in the joint is the development of arthritis. All joints with instability will develop arthritis; however the severity and the effect of the arthritis will vary from dog to dog.
Most dogs with a complete ACL tear show an immediate onset of lameness. While there may be some initial improvement over several days, there usually is a dramatic decline in limb function over time. There is no benefit gained from taking a "wait and see" approach. Stabilization of the joint soon after the injury has occurred is recommended.
A completely degenerated Cruciate Ligament can only be corrected by surgery. There are numerous surgical corrections currently being performed. A Tibial Tuberosity Advancement (TTA), which is the newest procedure, is often the best repair for bigger dogs.
Tibial Tuberosity Advancement is a somewhat less invasive surgery and dogs that receive the procedure will recover quicker initially. Your dog's surgeon will make a decision which procedure is the best option for your companion.
The TTA procedure involves making a cut in the front part of the tibia bone (tibial tuberosity) and advancing this portion of bone forward in order to realign the patellar ligament so that the abnormal sliding movement within the knee joint is eliminated. A special titanium bone wedge, pin, and staple are used to secure the bone in place.
After surgery, you can continue to give your pet a prescribed pain reliever to minimize discomfort. It's also extremely important to limit your dog's activity and exercise level during this post-operative period. Rehabilitation exercises can be done in your home. Rehabilitation therapy should be continued until your dog is bearing weight well on the operated limb (typically eight weeks after surgery). Detailed instructions will be given to you after the surgery.
The healing process will be monitored by the surgeon with follow-up exams scheduled approximately two weeks and eight weeks after the surgery. By eight weeks after surgery, the bone will be healed together. By 16 weeks after surgery, most dogs are fully weight-bearing on the operated limb and exercise restriction can be lifted at this time.