What Is a Flexor Muscle?

The flexor line is also known as the "finger flexor folds" and "flexor flexion." Thick and obvious grooves on a certain part of the palm joint of the fingers. It is formed during fetal development and growth, and it tends to deepen significantly with the increase of joint flexion and extension. There are two sets of flexor folds on the thumb of the human hand, and three sets of flexor folds on the other fingers. ^[1]