A cruciate ligament tear: Is a knee brace right for your dog?
We receive a lot of questions from dog owners about knee braces. This is an area where it is especially important to understand when a brace may help—and when it should not replace standard veterinary treatment.
The most common reason owners look for a knee brace is a cranial cruciate ligament tear.
And this is where we want to be absolutely clear:
If a dog is a suitable candidate for surgery to treat a cranial cruciate ligament tear, we do not consider a knee brace an equivalent alternative to surgery!
Why?
What Happens When the Cranial Cruciate Ligament Tears?
The cranial cruciate ligament is one of the key structures that keep the knee joint stable. It helps maintain the correct alignment of the thigh bone (femur) and shin bone (tibia), limiting unwanted movement and rotation between them.
When the ligament is partially or completely torn, the joint loses this stability.
As the dog puts weight on the leg, the tibia shifts abnormally relative to the femur, disrupting the knee's normal biomechanics. This can lead to pain, limping, progressive degenerative changes and further damage to structures within the joint, including the menisci.
This is why treating a cranial cruciate ligament tear requires more than simply "supporting the knee from the outside".
Why Is Surgery the Preferred Option?
A dog's knee works differently from a human knee. The forces generated when the dog puts weight on the leg, together with the anatomy of the upper tibia and the slope of the tibial plateau, play an important role.
When the cranial cruciate ligament can no longer do its job, the knee becomes abnormally unstable.
Modern surgical techniques can stabilise the knee's biomechanics in ways that an external brace simply cannot.
For this reason, a dog with a suspected cranial cruciate ligament tear should first be examined by a veterinarian, ideally one specialising in orthopaedics, who can confirm the diagnosis and recommend appropriate treatment.
Deciding whether a patient is a suitable candidate for surgery is not the brace manufacturer's role.
Can a knee brace replace a torn ligament?
NO!
We believe it is essential to be open about this.
An external knee brace cannot restore the function of a torn cranial cruciate ligament, return the knee to its original biomechanics or provide 100% stability.
It can help control the range of motion, guide the limb and provide some external support. However, it cannot correct the underlying cause of instability within the knee joint.
That is why we will not present a knee brace as a substitute for surgery in a dog who is a suitable surgical candidate.
Does this mean knee braces have no role?
The answer here is less straightforward.
In practice, there is a difference between an owner deciding "surgery or a brace?" and a situation where a decision has already been made that surgery will not go ahead.
This might involve a very elderly dog, a dog with other health complications, a dog with cancer or one who cannot undergo surgery for other reasons.
In these cases, a brace is no longer competing with surgery.
Instead, it becomes one possible form of support within conservative or palliative care. Whether it could help needs to be assessed individually.
Even in this situation, a brace will not "fix" the knee. Its role may be to provide external support, offer some control over limb movement and, depending on the dog's condition, help them use the leg more easily.
This is why we would never say that every dog with a cranial cruciate ligament tear who does not undergo surgery needs a knee brace. They do not.
Each dog needs to be assessed individually.
Why might a knee brace extend across the hock?
When designing a brace for a dog with a cranial cruciate ligament tear who will not undergo surgery, our aim may extend beyond supporting the knee alone.
The knee and hock (tarsal joint) are biomechanically linked during hind limb movement. By controlling and limiting movement at the hock, we can therefore also indirectly influence movement at the knee.
For some dogs, we would prefer a brace that spans both the knee and hock rather than a shorter knee brace. This design allows us greater control over the movement of the entire limb.
However, the same limitation applies: even this type of brace cannot replace the function of the torn ligament or restore the knee's original biomechanics.
Sometimes, supporting the other leg makes more sense
There is another area where orthotics may have a role.
A dog with a painful or unstable hind leg will naturally shift more weight onto the other leg.
This places extra strain on that leg. In some dogs, we may therefore consider a custom-made brace to help support the healthy limb.
The aim here is not to treat the ligament tear in the affected leg, but to provide additional support to the leg bearing the extra load.
A knee brace for a cruciate ligament tear—Yes or No?
As manufacturers of custom-made braces, you might have expected us to give a clear YES.
But our answer is: it depends on whether a brace is appropriate for the individual case.
If a knee brace is intended to replace surgery for a cranial cruciate ligament tear in a dog who is a suitable surgical candidate, we do not consider that an appropriate use.
However, if surgery will not go ahead, or we want to support the other leg because it is bearing extra weight, we can discuss whether a custom-made brace could form part of the dog's ongoing care.
Our aim is to work alongside veterinary orthopaedic specialists.
The best results come when a veterinarian establishes the diagnosis and treatment plan, and we build on that by designing a custom-made device where its use truly makes sense.
Because getting a brace right starts long before it is made—with the right clinical indication.
Written by: Stephanie Mach, CCBW, CCRP (Veterinary Physiotherapist, CEO of Animal Prosthetics)