One of the Most Common Knee Surgeries May Be Doing More Harm Than Good

What the 10-Year Study Found

Researchers in Finland studied 146 adults, ages 35 to 65, who had ongoing knee pain from a degenerative (worn, not traumatically injured) meniscus tear and no arthritis yet. Half received the real surgery — arthroscopic partial meniscectomy, in which the damaged tissue is trimmed away. The other half received a sham procedure: identical incisions, the same time under anesthesia, the same instruments moving inside the joint — but nothing was removed. Neither the patients nor the people scoring the results knew who received which treatment. This placebo-controlled design is one of the most rigorous ways to test whether a surgery itself actually works, or whether people simply feel better because they had an operation.

• Pain and function scores remained nearly identical between the two groups at every follow-up — out to 10 years.
• Arthritis on X-ray progressed in 81% of the real-surgery group versus 70% of the sham-surgery group.
• Roughly 1 in 8 patients who had real surgery later needed a knee replacement or realignment procedure, compared with about 1 in 25 in the sham group.

One detail makes the finding especially striking. For the first five years the two groups looked almost identical. Only in the second half of the decade did the real-surgery group’s knees begin to pull away — more pain, more functional loss, and faster joint degeneration.

One of the lead researchers put it bluntly: the idea that this kind of pain is caused by the tear and fixed by removing it “does not withstand critical examination.”

A tear on the scan.
Not always the reason for the pain.

Why a Torn Meniscus Isn’t Always the Problem

The meniscus is a C-shaped piece of cartilage that cushions and stabilizes the knee. Like skin or hair, it naturally wears with age. That wear frequently shows up on an MRI as a “tear” — even in a completely pain-free knee.

In studies of adults over 40 who have no knee symptoms at all, roughly 1 in 5 still show a meniscus tear on their scan.

So when an MRI reveals a worn meniscus in a knee that also hurts, the tear is not automatically the source of the pain. (A knee that is truly locking or catching is a different situation and deserves a surgical opinion.) For everyone else, simply seeing a tear on the scan does not answer the question of what is actually causing the symptoms.

So What Is Causing the Pain?

Is there a common, well-researched answer? Often, yes.

Many people with a “torn” meniscus on their MRI actually have a different problem: pain around or behind the kneecap. Doctors call this patellofemoral pain.

Here is how it usually develops.

When the muscles around the hips are weak, the whole leg moves a little differently with every step. That change in movement puts extra stress through the knee. At the same time, tight muscles in the front of the thigh, at the front of the hip, or along the outer side of the thigh can pull the kneecap slightly off its normal path.

Over months or years, that small shift in how the kneecap moves creates irritation and pain — even when the meniscus and the rest of the joint look fine.

The good news is that this kind of pain responds well to the right kind of exercise. Strengthening the hip muscles and the knee muscles together works better than focusing only on the knee. Hands-on treatment and careful stretching can also help, but they work best when they are chosen for the specific problems found during a thorough exam — not applied the same way to every patient.

Diagnosis First, Then Rebuild

At Performance Sport Care in Walnut Creek, this is the kind of case we see often. Dr. Douglas Cancel is a sports chiropractor and former national-level competitive bodybuilder who built the practice around one idea: find out what is actually driving the knee pain before deciding how to treat it, then rebuild strength and function around that answer through a combination of chiropractic care and supervised strength rehabilitation.

Many patients we see have already tried physical therapy that did not help. That is not surprising when you look at how the diagnosis is often made. A short conversation and a quick exam are followed by an MRI. Treatment then gets built around whatever the scan shows — frequently the meniscus.

If no one first checks the strength of the hip muscles, the tightness of the thigh muscles, or how the kneecap moves in its groove, even a carefully run physical therapy program is aimed at the wrong problem. Failing that kind of program does not mean nothing will help. It means the plan was never built around the real diagnosis.

One patient had been told for nearly a year that her meniscus was the reason surgery kept being recommended. Our exam showed something different. There was no locking and no catching. What we did find was clear weakness in the hip muscles and a kneecap that was not tracking properly. Those findings pointed straight to pain around the kneecap.

Working on that combination, step by step, produced more improvement in four to six weeks than a year of focusing on the wrong diagnosis.

No single technique is a cure-all. The research does not support that claim for any type of provider. What the research does support is matching the right approach to the right diagnosis — and that process starts with an exam designed to find it.