The oath hand

Definition

In the typical position of the oath hand, thumb, index and middle finger are stretched and the ring finger and little finger are bent. In medicine, the hand of oath refers to a symptom that occurs due to paralysis of the median nerve. The hand can no longer be clenched into a fist. If the patient is asked to make a fist, the thumb, index and middle finger remain stretched out, as with the hand to the oath.

Accompanying symptoms of a swearing hand

The loss of the flexor muscles of thumb, index and middle finger leads to the oath hand. This is caused by damage to the median nerve. In addition to the flexor muscles of the hand, the median nerve also supplies other muscles with motor power.

These are also affected by the damage. A failure of the other thumb muscles is particularly noticeable clinically. Patients can no longer hold a bottle tightly.

The opposition between thumb and little finger, i.e. the opposition of the thumb to the other fingers, is also limited. There are also sensitivity disorders. The median nerve supplies the skin on the inner side of the hand of the thumb, index and middle finger as well as the fingertips of these fingers also on the outer side of the hand with sensitive information.

Damage to the median nerve, which leads to the formation of a swearing hand, is always associated with pain. Nerve pain is not necessarily comparable with other pain such as neck or toothache. They are often described as burning and shooting.

Especially in the area of the hand that is sensitively supplied by the median nerve, painful sensations and numbness occur. In addition to the innervation of the muscles of the hand, which is required for the flexion of the thumb, index and middle finger, the median nerve also sensitively supplies parts of the hand. As already described, this also affects the thumb, index and middle finger on the inside of the hand, as well as the fingertips of these fingers on the outside of the hand. These areas require the median nerve in order to transmit their sensitive information to the brain. If the median nerve is damaged, these areas are perceived as numb.