The most common orthopedic condition that is seen in small animal veterinary medicine is trauma to the Cranial Cruciate Ligament of the stifle of the rear leg. This is the knee. Please see Figure 1. The Cranial Cruciate Ligament is comparable to the Anterior Cruciate Ligament (ACL) in people.
What Causes Stifle Injuries in Dogs?
In people, acute injury to the ACL occurs most often when playing soccer, basketball, football, skiing, or even jumping on a trampoline. However, injury to the Cranial Cruciate Ligament in dogs is usually not associated with a single, traumatic, athletic event. Cranial Cruciate Ligament injuries in dogs are the result of multiple factors including:
- Leg Conformation
- Poor Physical Condition
What Are the Symptoms?
Often an owner who has a dog with a Cranial Cruciate Ligament injury will notice their dog is ‘off’ on one leg. This is more visible after the dog has been lying down and then stands up. They will be ‘toe touching’ on one of their rear legs. Many times the dogs will warm-out of the subtle lameness and will seem to improve.
Unfortunately, in most cases this is not the end of the problem. Subsequently, dog owners will notice that their dog will be lame when walking or running and their dogs are taking longer and longer to warm-out of the lameness. The lameness worsens and progresses to non-weight bearing.
How Is a Cranial Cruciate Ligament Injury Treated Initially?
Early in this process many dogs will be placed on a pain medication/anti-inflammatory and they will seem to improve. In most cases, once the lameness begins it will not resolve if the Cranial Cruciate Ligament is injured.
How Does This Injury Progress?
Most injuries start off as a partial tear of the Cranial Cruciate Ligament. This ligament is like a rope comprised of many small ligaments woven together. Over time all partial tears turn into a full tear of this ligament. As is the case with people—once a ligament tears in dogs it will not heal.
What Happens If a Cranial Cruciate Ligament Injury Is Left Untreated?
The job of the Cranial Cruciate Ligament in dogs is to prevent the tibia from sliding forward when the leg engages during weight bearing. Please see Figure 2. If the Cranial Cruciate Ligament is partially or completely injured, the Tibia will slide forward when walking, running, and jumping. This is called a Cranial Drawer Motion or a Tibial Thrust. This motion causes pain in the joint and leads to inflammation in the joint. The inflammation in the joint eventually causes damage to the cartilage that leads to arthritis.
What Is the Recommended Solution?
We recommend surgery to re-stabilize the joint to eliminate the Cranial Drawer Motion so that dogs can return to running, jumping, and rough play without pain. There are many different types of surgeries done to stabilize the joint. However, one surgery seems to be most beneficial to dogs with the fastest recovery and best overall long-term function. We recommend a Tibial Plateau Leveling Osteotomy (TPLO) to stabilize the stifle joint. This procedure, developed by Dr. Barclay Slocum more than 25 years ago, has improved the quality of life of hundreds of thousands of dogs since it was introduced.
The TPLO surgery entails:
- A night in the hospital where the dog is monitored very closely by 24-hour veterinary nursing staff.
- Only short leash walks to the bathroom and confining your dog to one floor of the house are required for the first four weeks after surgery.
- At week four dogs are encouraged to start walking therapy and moderate stairs.
- Most dogs can begin off-leash activity at eight weeks post operatively.
If your dog is showing any signs of rear leg lameness, it is important to have a thorough exam done by your regular veterinarian. If your veterinarian suspects an injury to the Cranial Cruciate Ligament, we would be glad to evaluate your dog at the Surgery Service of the Veterinary Referral Center of Northern Virginia located in Manassas. This surgical procedure is the most common surgery we do. During the past 15 years, the Surgery Service of the Veterinary Referral Center of Northern Virginia has performed more than 300 TPLOs each year.