Does arthroscopy help in osteoarthritis of the knee?

Photo of a woman with knee pain sitting on a bench (PantherMedia / Sanda Stanca)

Arthroscopy (keyhole surgery) is sometimes recommended for treating osteoarthritis of the knee. It involves rinsing the knee joint with a solution (lavage) and sometimes also smoothing the cartilage surfaces. But studies have shown that arthroscopy doesn’t have any advantages.

Osteoarthritis of the knee develops when the cartilage that covers the ends of bones in the joint wears away. This causes pain and means you can't move your knee as much. At first, the pain is felt only when the joint is moved, but later on it may also occur when the joint is resting, or at night. If osteoarthritis gets worse, the joint can become stiffer and deformed.

Some doctors recommend using knee arthroscopy to treat the condition. But this surgery can’t achieve the often-stated goal of getting rid of – or at least reducing – the symptoms. Plus, it can have side effects and lead to complications like deep vein thrombosis, bleeding, infections and pain. It also takes several weeks to recover from arthroscopy.

What happens during arthroscopy?

Arthroscopy is a surgical procedure that is done using a local or general anesthetic. After a small cut is made in the skin and in the joint capsule, an arthroscope (a special type of endoscope) is inserted into the knee joint. The arthroscope is a thin, tube-like instrument with a small camera on it that shows the inside of the knee. So arthroscopy can also be used to examine the knee joint.

Arthroscopy isn't typically used for diagnosis purposes only, though, but also for treatment. A second cut is then made to insert small instruments like scissors or shaver blades into the joint.

When arthroscopy is used for treatment purposes, two things can be done:

  • Lavage (washing out the joint): During lavage, the joint is rinsed with a salt solution. The goal is to remove any loose particles like cartilage or tissue fibers in the joint fluid, and to reduce any inflammation in the joint.
  • Debridement: Debridement involves smoothing rough cartilage surfaces and removing loose bits of cartilage using various instruments. It is followed by joint lavage.

Can arthroscopy help?

Together with researchers from the University of Bern (Switzerland), the Institute for Quality and Efficiency in Health Care (IQWiG, Germany) assessed whether treatment with arthroscopy helps in osteoarthritis of the knee. For this purpose, the group of researchers analyzed the results of eleven studies that included a total of about 1,200 women and men. These studies lasted between 6 and 36 months.

Five studies looked at whether patients who had a knee lavage were doing better than those who did not. In some studies, one group of participants had an arthroscopy while the others only had a "pretend" procedure.

The results of these studies clearly showed that treatment with arthroscopy isn’t effective: After arthroscopy, participants didn’t have less pain or fewer symptoms than those in the "no treatment" comparison group.

The other six studies looked at the effectiveness of treatment with arthroscopy compared with the effectiveness of other treatment options. They didn’t find any advantages there, either.