When there is a joint injury like a cranial cruciate ligament (CCL) rupture, it is important for the vet to try to preserve the menisci to the greatest extent possible. Loss of all or part of a stifle’s meniscus has the potential to accelerate the breakdown of articular cartilage with resultant DJD (Degenerative Joint Disease). The more of the meniscus that is lost through injury or through surgical removal, the less stable the joint will be in future, and the greater the potential for DJD, i.e. arthritis. The risk of further damage to the menisci is minimized by greatly reducing activity after ligament injury while the dog’s body re-establishes stability in the joint.
Whether or not your dog has surgery to temporarily stabilize the joint after ligament rupture, long term joint health is best assured by careful restriction during a slow return to normal activity over a period of at least several months, and by avoiding unnecessary surgical removal of all or part of the meniscus. People are sometimes told that their dog’s meniscus is damaged and that the meniscus cannot heal on its own therefore surgery is always required for meniscal injury. This is not true. In fact, there are two basic methods used by the body to repair meniscal damage:
1) Extrinsic – When meniscal tear occurs, a fibrin clot forms within its margins. This fibrin clot contains factors that act as agents for reparative cells to migrate and develop. Further inflammatory response and angiogenesis result in healing of the lesion in about 10 weeks in the dog. It may take months or even years for the scar tissue to change into fibrocartilage, resembling that of the meniscus. Differences between the newly formed fibrocartilage and mature fibrocartilage are recognizable and include increased cellularity and, at times, increased vascularity in the repair tissue.
2) Intrinsic – The cells within the meniscus itself have an inherent capability to generate a healing response. The cells of the meniscus are assisted by the fibrin clot, which not only acts as a scaffold, but also provides stimuli to promote healing.
Why should I be wary of a veterinary surgeon removing my dog’s mensicus during ccl repair surgery?
There are many veterinary surgeons out there who are much too quick to carve off parts of a damaged meniscus when the dog would be far better off with the joint left alone to recover using its own resources. The menisci are now known to play an important role in the complex biomechanisms of the knee. But just a few decades ago doctors believed the menisci were functionless tissue that could be removed without consequence. Surgeons routinely removed the entire meniscus if there was any indication that it was even slightly damaged or for no reason simply as part of their standard procedure when doing any stifle surgery. This resulted in crippled dogs as Degenerative Joint Disease developed in the joints.
Eventually the more observant doctors woke up to the fact that the menisci were important joint components, and in recent years the more enlightened surgeons have become less aggressive in removing all or part of the meniscus. But there are still many vet surgeons who cut far too much of a meniscus away. Some of these guys just can’t stop themselves from getting in there and excising something. Their approach is often, “When In Doubt, Cut It Out” and is a rule of thumb often used in canine stifle surgery. They won’t usually tell clients that of course. The history of surgery in general is filled with examples like this of too-aggressive surgical intervention. Never be too trusting of a surgeon. They became surgeons to cut; not to tell you no cutting is needed.
About the Dog Meniscus – http://home.earthlink.net/~tiggerpoz/id16.html