Can a Dog Tear the Other Cruciate Ligament After TPLO Surgery?
One of the most common concerns owners have after TPLO surgery is:
"Will my dog tear the other cruciate ligament too?"
Unfortunately, the answer is sometimes yes.
Dogs that rupture one cruciate ligament often place increased strain on the opposite hind leg — and many dogs also have underlying joint and biomechanical factors that affect both knees over time.
The good news is that this does not happen to every dog, and there are ways to support strength, movement quality, weight management, and recovery that may help reduce overload on the opposite limb.
At Balance Vet Rehab, we regularly help dogs from Brisbane, Gold Coast, and Scenic Rim recovering from cruciate injuries and supporting long-term mobility after TPLO surgery.
Why Do Dogs Tear the Other Cruciate Ligament?
Cruciate ligament disease in dogs is usually not caused by a single traumatic accident.
In many dogs, the ligament gradually weakens over time due to a combination of:
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joint instability
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inflammation
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conformation
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genetics
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muscle weakness
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body weight
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biomechanics
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and long-term wear within the knee joint
This means that even when one knee is repaired surgically, the opposite knee may already have early degeneration developing.
Many owners are surprised to learn that the “good leg” is often not completely normal — it may simply not have ruptured yet.
How Common Is It?
Studies suggest a significant number of dogs that rupture one cruciate ligament will eventually injure the other knee as well.
For some dogs, this happens:
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within months
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during rehabilitation
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or several years later
For others, it may never occur.
The risk varies depending on:
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breed
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body condition
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age
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muscle strength
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activity levels
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existing arthritis
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and overall biomechanics
Large breed dogs and overweight dogs may carry a higher risk because of the increased forces placed through the knees.
Not sure whether gait analysis may help your dog? We’re happy to talk through your concerns first.
Why the Opposite Leg Is Vulnerable During Recovery
After TPLO surgery, dogs naturally shift more weight onto the opposite hind leg during healing.
Even when recovery is progressing normally, this can temporarily overload the “good” limb.
If the opposite cruciate ligament is already weakened, increased compensation may contribute to:
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inflammation
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partial tearing
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or eventual rupture
This is one reason rehabilitation focuses heavily on restoring safe, symmetrical movement patterns rather than simply encouraging activity.
Signs the Other Cruciate Ligament May Be Struggling
Owners sometimes notice subtle changes before a full rupture occurs.
Possible warning signs include:
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intermittent limping on the opposite leg
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stiffness after rest
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difficulty rising
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bunny hopping
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sitting crookedly
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reduced willingness to jump
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slowing down on walks
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shifting weight between hind legs
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or occasional “off” days after activity
Some dogs develop only mild signs initially, especially with partial cruciate tears.
We also have related information on:
Signs of TPLO Failure or Complications
which may help owners distinguish between recovery-related limping and issues involving the opposite leg.
Can Rehabilitation Help Reduce the Risk?
No rehabilitation program can guarantee prevention of future cruciate injury.
However, rehabilitation may help reduce unnecessary overload and improve how dogs use both hind limbs during recovery.
Rehabilitation commonly focuses on:
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rebuilding muscle mass
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improving balance and coordination
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reducing compensation patterns
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controlled strengthening
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weight management support
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improving gait quality
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gradual return to activity
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and identifying early asymmetries
Dogs recovering too quickly or returning to unrestricted activity too early may overload healing tissues or compensate heavily onto the opposite limb.
This is why controlled progression matters.
Just gathering information? We’re happy to explain how rehabilitation may support recovery and long-term mobility with no obligation.
Does TPLO Surgery Cause the Other Cruciate Ligament to Tear?
This is a common misunderstanding.
TPLO surgery itself does not directly damage the opposite knee.
However, dogs recovering from one cruciate injury often:
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compensate heavily
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redistribute weight
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change movement patterns
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and reveal underlying disease already present in the second knee
In many cases, the opposite ligament was already vulnerable before the first surgery even occurred.
Which Dogs Are Most at Risk?
While any dog can potentially injure the opposite cruciate ligament, risk may be higher in:
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Labrador Retrievers
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Golden Retrievers
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Rottweilers
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Boxers
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Staffordshire Bull Terriers
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overweight dogs
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highly active dogs
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dogs with poor muscle mass
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and dogs with existing arthritis
Older dogs may also face additional challenges because reduced muscle strength and arthritis can increase joint loading.
We’ll soon also cover:
Can Older Dogs Have TPLO Surgery?
including when conservative rehabilitation-focused management may be a reasonable option.
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How Long After TPLO Can the Other Cruciate Tear?
There is no exact timeline.
Some dogs rupture the opposite ligament:
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within weeks
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within months
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or years later
Others never rupture the second knee at all.
Owners should remember that recovery is not just about the operated leg — protecting the whole dog’s movement and strength matters too.
Returning to Running Too Soon
One of the biggest risks during recovery is progressing activity too quickly.
Owners often feel encouraged when their dog suddenly seems energetic again. However, dogs commonly feel better before tissues, strength, and coordination are fully restored.
Sudden high-intensity activity may increase overload through:
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the healing limb
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the opposite hindlimb
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and the spine and hips
We’ll soon also have a dedicated page on:
When Can My Dog Run After TPLO Surgery?
because safe return-to-exercise progression is one of the most important parts of recovery.
Supporting Both Hind Legs After TPLO
Long-term success after cruciate surgery is about more than bone healing alone.
Many dogs benefit from:
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progressive strengthening
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careful weight control
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low-impact exercise
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hydrotherapy
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gait assessment
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home exercise programs
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and monitoring for early signs of overload
At Balance Vet Rehab, we regularly assess movement patterns in dogs recovering from TPLO surgery across Brisbane, Gold Coast, and Scenic Rim, helping owners better understand recovery progression and long-term mobility support.
You may also find these pages helpful:
Reassurance for Owners
Hearing that the opposite cruciate ligament could rupture can feel discouraging.
But it’s important to remember:
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not every dog tears the second ligament
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early management may help reduce overload
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and many dogs still do extremely well long term after cruciate surgery
The goal is not simply getting through surgery — it is supporting the whole dog’s movement, comfort, and long-term function.
Concerned About Your Dog’s Recovery or the Opposite Leg?
If your dog is showing signs of compensation, weakness, stiffness, or limping after TPLO surgery, a rehabilitation-focused assessment may help identify movement issues early and support safer long-term recovery.
Balance Vet Rehab works with post-TPLO dogs across Brisbane, Gold Coast, and Scenic Rim with a strong focus on practical mobility, strength rebuilding, and reducing compensation patterns.