Adduction

Adduction is a term used in anatomy and physiology to describe movement of a body part toward the midline of the body or toward the center of a structure. It is the opposite of abduction, which denotes movement away from the midline. The concept applies to many joints and regions, including the limbs, digits, scapulae, jaw, and vocal apparatus.

Common examples include shoulder adduction, where the arm is brought toward the trunk; hip adduction, where the thigh moves inward toward the midline; and finger adduction, where the fingers are drawn toward the middle finger. Toe adduction occurs similarly toward the second toe. Scapular adduction, or scapular retraction, pulls the shoulder blade toward the spine. Muscular contributors include the pectoralis major and latissimus dorsi for the shoulder, the adductor muscle group for the hip, and the palmar interossei for finger adduction. The great toe often adducts toward the second toe via the adductor hallucis.

In addition, adduction can refer to movements of the jaw, such as closing the mouth, and to the vocal apparatus, where adduction of the vocal folds closes the glottis during phonation. Understanding adduction alongside abduction helps describe many functional movements and informs clinical assessment and rehabilitation.

The term derives from Latin adducere, “to bring toward.”