Thessaly test

What you are asked to do

You stand on the painful leg, holding the surgeon's hands so you cannot fall. With the knee bent about 20 degrees, you turn your body and knee inwards and outwards three times. The healthy leg is usually tested first so you know what normal feels like.

If the meniscus is torn, you may feel discomfort along the inner or outer side of the knee, a catch, or a sense that the knee might lock. Stop and tell the surgeon if the pain is sharp.

What it tells the surgeon

Standing loads the knee with body weight, much as happens when you turn on a football pitch or padel court. That makes the test good at reproducing the twisting pain that patients with meniscus tears describe.

Like every meniscus test, it is not perfect on its own. Kneecap pain, arthritis or a fresh ligament injury can also hurt when twisting. The surgeon combines it with the McMurray test, joint line tenderness and your history before deciding whether an MRI is needed.

When it is not done

The test is skipped if you cannot bear weight safely, if the knee is very swollen or unstable after a fresh injury, or if balance is a concern.