In medicine, the term supination describes the movement of an extremity. The word supination comes from Latin and means something like "bent back position". The opposite movement to supination is pronation.
There is supination of the hand or forearm and supination of the foot. Both are presented in the following text.
In the Supination of the forearm are playing spoke (radius) and the Cubit (Ulna) a role. In the supination position, the ulna and radius become one Parallel position brought. The forearm rotates in the supination movement Arm to the "outside". With an outstretched arm with Palm down so the arm is rotated so that the Palm up shows and the Thumbs away from the body. The hand and forearm are rotated during this movement. This comes from the movement of the Forearm muscles come about that arise or start at the ulna and radius. The joints involved are called Articulatio radioulnaris proximalis and Articulatio radioulnaris distalis. The following muscles are involved in supination of the forearm:
- Brachioradialis muscle
- Biceps bracchii muscle
- Supinator muscle.
Supination of the foot
When the foot is supinated, the outer side of the foot is moved downwards and the middle side of the foot upwards. The heel is not moved. So the foot bends outwards. The muscles responsible are called:
- Gastrocnemicus muscle
- Soleus muscle
- Tibialis posterior muscle
- Flexor hallucis longus muscle
- Flexor digitorum longus muscle
- Tibialis anterior muscle.
The joints involved are called:
- Articulatio subtalaris
- Articulatio talocalcaneonavicularis
The first two are the main muscles for this movement. Malpositions of the feet can lead to over- or under-supination. This can lead to an incorrect load on the foot, which in turn can be harmful to tendons and muscles. Therefore, there are different shoes for running for the different foot positions. The causes of foot deformities are usually congenital, acquired through obesity or caused by excessive fatigue.
There are two donkey bridges to help you remember supination and pronation.
"In supination, the hand is in the form of a bowl for soup, and in pronation, the hand is like cutting bread".