Hello and welcome. My name is ***** ***** I'm a biologist with a special interest in canine health. I'm sorry to hear of your dog's injury.
Veterinary orthopedic surgeons estimate the success rate of this surgery to be about 85% to 95%. When the surgery does fail, it's often due to the owner being unable or unwilling to restrict the dog's exercise following surgery. Sometimes a dog will tear the ligament in the other leg because he/she will put too much weight on it while trying to run or jump while favoring the injured leg. A dog that is overweight is also more likely to experience a surgical failure.
There are several different types of ligament repair that can be done. Each vet will have their preferences. Tibial plateau leveling osteotomy (TPLO) is often recommended for very active or large dogs. There are two other types, which are very similar to each other that are often used on smaller, less active dogs. If you want to read more about the different types, the following site has diagrams:
One of my collies had this same injury at age 9 - chasing a squirrel. I opted for surgery, and until age 13, had no additional problems with the knee. Then she stretched the ligament severely. The orthopedic surgeon didn't want to do surgery on a dog that age, and he recommended something called conservative management.
If you decide against surgery, you may have to consider it. If your dog is overweight, weight loss is one part of it. Exercise restriction is a very important step. (That's important regardless of the approach you take, including surgery). Use of anti-inflammatories, such as Rimadyl, is also included. You can read more about conservative management here:
A brace for the knee can be very useful. The braces cost $200 to $350, depending on the dog’s size. The brace allows the dog to be a bit more active while protecting the stifle so healing can take place. Here is a source for braces:
I found the company to be helpful, and my dog adjusted to the brace within a week.
One of the big risks associated with a ligament tear in the knee is that the other knee will suffer the same fate. That's why exercise restriction is so important, regardless of the treatment method. Also, the knee where the tear occurred is more prone to developing arthritis as time passes. You may want to consider giving a glucosamine/chondroiten supplement to help prevent that. An injected compound called Adequan is even more effective, but it's only available through your vet and is expensive.
Here is a link to an article on the subject of torn knee ligaments from the respected holistic magazine, The Whole Dog Journal. It gives the pros and cons of each method.
For conservative management to work, the owner has to be diligent about exercise restriction for about 6 months. Surgery has similar restrictions, but sometimes for a shorter amount of time.
If you have more questions, let me know in a REPLY. I hope that whatever you decide to do, it will work out well.
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