Frequency distribution

Male patients are more likely to be affected (four times more frequently than women), the age peak being between 20-40 years.

Complaints

It is sometimes difficult to distinguish lunatum malacia from tendosynovitis, especially because tendosynovitis is much more common than lunatum malacia. How can one be sure of this? In contrast to tendosynovitis, where the pain usually affects several points and also occurs on the palm of the hand, lunatum malactia causes pain in the hand, especially at the beginning of the disease, in a strictly defined manner on the lunate bone, i.e. centrally on the side of the back of the hand.

A further factor is of course also whether they carry out activities that are associated with a risk to the lunate bone. For example, if they do not perform any activities involving strong vibrations in their hands, this makes lunatum malacia much less likely.

Ulna (ulna)
Spoke (radius)
Wrist
Stylus process (Processus styloideus ulnae)
Moon leg (Os lunatum)
Scaphoid (Os naviculare)

Diagnostics

The diagnosis is often made using a combination of manual tests and wrist imaging. In the so-called ballottement test of the wrist, the moon bone is moved back and forth by the examiner against its neighbor, the scaphoid. If the stability between these two carpal bones is reduced, this is called a positive ballottement test.

This shearing movement is often painful for the patient, as is manual pressure directly on the lunar bone. If you suspect lunatum malacia, an X-ray of the hand should be taken first. The x-ray is relatively inexpensive and most practices have an x-ray machine, so the distance and waiting times are usually short.

The disadvantage, however, is that the X-ray only shows quite advanced stages of lunatum malacia, which have already caused considerable damage to the bone. A lunatum malacia can therefore only be confirmed by X-ray, but never excluded. In the following, the stages that can be distinguished in an x-ray image are listed: Stage 1: In some cases no changes are visible here.

If necessary, a slight compression of the lunar bone can be seen. The outer contour is not interrupted. Stage 2: Circular bright spots are visible in the x-ray image and the outer edge becomes shapeless.

Stage 3: At this stage the moon bone has already disintegrated, the wrist structure becomes unstable. Stage 4: In addition to the disintegrated moon bone and unstable wrist, arthrosis of the wrist now occurs. If no changes are visible in the x-ray image, but the clinical signs are consistent with lunatum malacia and there is still a strong suspicion, a magnetic resonance tomography (MRI) of the wrist is also performed.

Here, bone decay is already visible in stage 1.

Stage 1: Partially no changes are visible here yet. If necessary a slight compression of the lunar bone can be seen. The outer contour is not interrupted.
Stage 2: Circular bright spots are visible in the X-ray image and the outer edge becomes misshapen.
Stage 3: At this stage, the lunar bone has already disintegrated and the wrist structure becomes unstable.
Stage 4: In addition to the decayed lunar bone and unstable wrist, arthrosis of the wrist now occurs.