Diagnosis

After an inner meniscus rupture, the affected joint space is clearly painful under pressure. There are several diagnostic meniscus tests to check whether it is actually an inner meniscus tear:

Steinmann 1 – Test The examiner rotates the knee joint bent by 90 degrees. If the patient reports increased pain in the inner knee joint when rotating it outwards, damage to the inner meniscus is likely.
On the other hand, if the outer meniscus is torn, the pain will be more pronounced in the outer knee joint when the patient rotates inwards.

The distinction between a tear of the inner meniscus and an outer meniscus is then made by means of the exact localization of the pain, whereby increased pain in the inner joint space is more likely to indicate a tear of the inner meniscus. An X-ray image is usually taken to rule out bony damage (e.g. in the form of a fracture), but a torn inner meniscus cannot be seen in an X-ray image. An MRI (magnetic resonance tomography or synonymously magnetic resonance imaging) image would be necessary for this.

Even an MRI scan of a torn meniscus cannot diagnose it with 100% certainty. Especially the small and degenerative tears, so-called age tears, are sometimes difficult to see in an MRI.

Steinmann 2 – Test The examiner slowly bends the knee joint from the stretched position further and further towards 90 degrees of flexion.
If the patient reports a pain in the knee joint that moves from front to back, this indicates meniscus damage.
Payr sign Is tested on the patient who remains in a cross-legged position. The examiner presses the affected knee towards the floor. If the patient reports pain in the inner joint space, this indicates an inner meniscus lesion.
Other meniscus tests indicating a meniscus lesion are the Apley sign, the McMurray sign, the Böhler sign and the Merke sign.