PALMARIS LONGUS :
The palmaris longus is a muscle visible as a small tendon between the flexor carpi radialis and the flexor carpi ulnaris,
although it is not always present. It is absent in about 14 percent of the population;
however, this number varies greatly in African, Asian, and American population.
Absence of the palmaris longus does not have an effect on grip strength.
The palmaris longus muscle can be seen by touching the pads of the fourth finger and thumb and flexing the wrist.
The tendon, if present, will be visible in the midline of the anterior wrist.
Origin : medial epicondyle of humerus
Insertion : palmer apponurosis & flexor retinaculor of the hand
Nerve Supply : medial nerve
Action/Exercise : wrist flexion
CLINICAL IMPORTANCE : The palmaris longus muscle is the most popular for
use in tendon grafts for the wrist due to the length and diameter of the palmaris longus tendon,
and the fact that it can be used without producing any functional deformities.
When a tendon becomes ruptured in the wrist, the palmaris longus tendon may be removed from the flexor retinaculum and grafted to take the place of the ruptured tendon.