If your dog has torn its cruciate ligament or continues to limp despite treatment, the problem may not be the ligament itself—it could be the meniscus.
The meniscus is one of the most important structures inside the knee and one of the most common sources of ongoing pain following a cruciate ligament injury. At Sandringham Veterinary Hospital, we carefully examine the meniscus during every cruciate surgery because identifying and treating a torn meniscus is essential for a successful recovery.
So, what is the meniscus, how does it become damaged, and why does it cause so much pain?
What Is the Meniscus?
The meniscus is a tough, rubbery pad of cartilage that sits between the femur (thigh bone) and the tibia (shin bone) inside the knee (stifle joint).
Dogs have two menisci in each knee:
- The medial meniscus – located on the inside of the knee.
- The lateral meniscus – located on the outside of the knee.
The meniscus has several important functions:
- Acts as a shock absorber.
- Distributes weight evenly across the joint.
- Helps stabilise the knee.
- Protects the smooth cartilage covering the bones.
Without a healthy meniscus, the knee experiences increased wear and tear, leading to pain and arthritis.
How Does the Meniscus Tear?
The vast majority of meniscal tears occur after a cranial cruciate ligament (CCL) rupture.
When the cruciate ligament tears, the knee becomes unstable. Instead of moving smoothly, the femur slides abnormally on the tibia every time your dog takes a step.
The meniscus becomes trapped between the two bones and is repeatedly crushed.
The medial meniscus is injured far more commonly because it is firmly attached to the tibia and cannot move out of the way.
Some tears occur at the time of the cruciate injury, while others develop days or weeks later as the unstable knee continues to damage the cartilage.
Why Does a Torn Meniscus Cause So Much Pain?
Imagine having a small pebble inside your shoe.
Every step reminds you it’s there.
You could wear the strongest, most supportive shoes available, but until the pebble is removed, every step remains painful. A torn meniscus causes pain in much the same way.
- Every time your dog bends the knee, the torn piece of cartilage becomes trapped between the bones.
- This causes pain with every step.
- The joint becomes inflamed and uncomfortable.
- Even after TPLO surgery has stabilised the knee, the torn meniscus can continue causing pain if it is left untreated.
Why Doesn’t the Meniscus Heal on Its Own?
Unlike many other tissues in the body, most of the meniscus has a very poor blood supply.
Blood carries the oxygen and healing cells needed for damaged tissue to repair itself.
Because the inner part of the meniscus receives very little blood, most tears have little ability to heal naturally.
Instead, the damaged fragment continues to move within the joint, causing ongoing pain and irritation.
What Are the Signs of a Torn Meniscus?
Dogs with a torn meniscus commonly show:
- Persistent limping after a cruciate ligament injury.
- Sudden worsening after initially improving.
- Difficulty getting up after resting.
- Reluctance to run, jump or climb stairs.
- Pain when the knee is bent.
- Occasionally, a clicking or popping sound from the knee.
If your dog develops these signs, a meniscal injury should be considered.
How Is a Torn Meniscus Diagnosed?
A thorough orthopaedic examination is the first step.
While X-rays are essential for assessing the bones and planning cruciate surgery, they cannot directly show a torn meniscus.
In many dogs, the diagnosis is confirmed during surgery when the meniscus can be carefully inspected.
Not every tear is obvious.
Some tears are large and easy to identify, while others are small, hidden or only visible after a meticulous examination.
This is why surgical experience is so important.
How Is a Torn Meniscus Treated?
The damaged portion of the meniscus is carefully removed while preserving as much healthy cartilage as possible.
This procedure is called a partial meniscectomy.
If a cruciate ligament rupture is also present, both problems are usually treated during the same surgery, often with a TPLO.
Once the painful torn fragment has been removed, many dogs become noticeably more comfortable within just a few days.
Why Experience Matters
At Sandringham Veterinary Hospital, we know that missing a meniscal tear is one of the most common reasons dogs continue to limp after cruciate surgery.
That’s why we carefully inspect the entire meniscus during every cruciate procedure.
Our goal is not simply to stabilise the knee but to identify and treat every source of pain, giving your dog the best possible chance of a full recovery.
Is Your Dog Limping After a Cruciate Injury?
If your dog has a cruciate ligament injury, ongoing knee pain or persistent lameness after TPLO surgery, a torn meniscus may be the cause.
At Sandringham Veterinary Hospital, we provide comprehensive orthopaedic assessment and advanced surgical treatment for cruciate ligament and meniscal injuries.
Call Sandringham Veterinary Hospital today to book an orthopaedic consultation and help your dog get back to a comfortable, active life.