knee injuries in dogs: signs + treatment options
Knee injuries in dogs are a common problem many pet owners face over the course of their pet's life. One of the most common orthopedic injuries to the knee that veterinarians see in the clinic is damage to the cranial cruciate ligament (CCL).
Where is the CCL in dogs?
The anterior cruciate ligament (ACL) is one of the supportive ligaments in the knee joint. Complete or partial tears of the ACL cause pain, swelling and often instability of the joint. In animals, because of a difference in anatomical terminology, we tend to use the term cranial cruciate ligament (CCL) more commonly, but the two terms are often used interchangeably.
Knee injuries in dogs
So, how do these injuries occur in pets? Well, it usually takes a severe twisting or jarring motion to cause the knee ligament to rupture, but studies suggest that around 75% of pets that suffer cruciate tears have a degree of predisposition due to genetics, obesity, age or concurrent disease.
Additionally, when one knee has suffered an injury, there’s a much increased chance of the other knee also suffering a tear within the next 12-28 months.
Signs + Symptoms
The clinical signs of a cranial cruciate ligament or disease can be vague and often overlooked by pet parents – especially since both legs may be affected.
Below is a list of the most common clinical signs noted; however, it is not an all-inclusive list. Many pet parents think their pets have painful hips or hurt their foot.
Other times, they may not realize their pet is experiencing discomfort until the ligament fully ruptures.
Common signs include:
- Sitting with legs to one side instead of sitting square
- Difficulty rising
- Difficulty jumping- into the car, onto the couch, etc.
- Decreased activity level
- Muscle atrophy of the affected leg(s)
- Thickening of the stifle (referred to as a medial buttress)
- Decreased stifle range of motion
- Stifle “popping”
- Three legged lameness
How are knee injuries in dogs diagnosed?
First and foremost, your veterinarian will do a thorough physical and orthopedic exam to try and localize where your dog is experiencing pain. This is not always easy to do, as dogs will get very excited and tense at the veterinary office and may not react to the manipulations that we use to try and localize the pain.
If the ligament is only partially damaged, this can really make the diagnosis difficult, because part of the ligament is still intact and may prevent abnormalities on physical examination.
Veterinarians also use radiographs and advanced imaging such as MRI’s to diagnose this disease. It should be noted that these are soft tissue structures we are discussing, so radiographs are not always useful in diagnosing this particular disease.
Treatment options for pets
Treatment recommendations in dogs are typically based on your pet’s age, weight and other complicating factors. With a cruciate rupture, the size of your dog does play a large role in deciding which treatment option may have the best chance of success.
Small dogs, those under 16 pounds, have a much greater chance of a good recovery without surgical intervention. About a quarter of these little dogs will do well with anti-inflammatory medication, STRICT rest and any necessary weight loss. In these small dogs, it is perfectly reasonable to try this conservative approach for four to six weeks. If your petite pooch’s comfort hasn’t vastly improved by the end of this time period, then surgery may need to be pursued.
Dogs over 16 pounds generally require surgical intervention to have a good outcome. Conservative management has not been found to be very effective for these larger pets. There are several surgical procedures that can be used to repair a ruptured cruciate ligament, including suture techniques that stabilize the joint from the outside. There are several different suture techniques, and together they have about an 85% success rate.
There are four popular options for cruciate ligament repair:
- extracapsular repair
- tibial plateau leveling osteotomy (TPLO)
- tibial tuberosity advancement (TTA)
Each has its benefits, and your veterinarian will recommend the surgery that is best for your dog. Here’s what you can expect in your post-operative pooch.
Also called lateral suture, lateral fabellar suture stabilization, or fishing line technique. With this procedure, the surgeon does not have to cut any bones or go into the dog’s joint. Instead, the surgeon uses a thick suture material on the outside of the joint to serve as a “replacement” to the torn ligament. This technique is most frequently used in smaller dogs, less active dogs, or older dogs. The main disadvantage is that the suture can fail (break) requiring further intervention.
Exercise restriction will be required for at least 8 weeks. Leash walks only—no running or jumping.
Your dog might be toe touching within a day or two after returning home, but it may take up to two weeks. A gradual return to function will happen over two months.
Tibial plateau leveling osteotomy (TPLO)
Tibial plateau leveling osteotomy (TPLO) involves cutting the back of the tibia (shin bone), rotating the cut portion, and implanting a specialized plate to hold the cut portion of the bone in this new position. It creates a new angle within the stifle (knee) joint so that when your furry family member steps down, the femur (thigh bone) doesn’t slide. In short, the procedure changes the angle of the bones so that the joint becomes more stable.
- Your dog will probably come home with a bandage over the entire leg.
- Strict exercise restriction will be required for 8 to 12 weeks.
- Your dog will likely be toe touching within a week, with a return to normal function expected two to three months post-operatively.
Tibial tuberosity advancement (TTA)
Tibial tuberosity advancement (TTA) involves cutting the front of the tibia (called the tibial tuberosity and the place where the quadriceps muscles attach to the tibia), rotating the cut portion, and placing an implant (different from the one used in a TPLO) to hold the cut portion of the bone in this new position. Similar to TPLO, this technique stabilizes the stifle by changing the angle of forces within the joint.
- Your dog will probably come home with a bandage over the entire leg.
- Strict exercise restriction and confinement will be required for at least 12 weeks.
- Your dog will likely return to normal function within three to four months.
This technique uses a specialized toggle-suture implant that allows for more accurate placement of the suture material and a stronger fixation (as compared to the extra-capsular suture). Tightrope® can be used in larger and more active dogs than extra-capsular suture and does not require any bones to be cut (although it does involve holes drilled into the femur and tibia).
The main disadvantages are implant failure and proximity to a surgeon that can perform the procedure.
Does pet insurance cover knee surgery?
Medical advances and better post-operative care mean that there’s never been a better chance of getting your dog back on all four feet in record time. However, advanced surgical techniques like tibial tuberosity advancement (TTA) and then after-care like hydrotherapy can come with a hefty price tag – surgery alone can top $5,000.
When you consider that Americans spend over $1.2 billion dollars per year on CCL repairs alone, you can see why more pet owners are looking to dog insurance to help manage the financial trauma.