In this anatomy lesson, I’m going to demonstration abduction and adduction, which are angular body movement terms that have a structure moving either toward or away from a midline reference point on the body.
Unlike flexion and extension movements, which mostly take place within the sagittal plane, you’ll notice that abduction and adduction motions mostly take place within the frontal, or coronal, plane. However, the thumb is a notable exception to this rule, as it moves within the sagittal plane during abduction and adduction when in the anatomical position.
What is Abduction?
Abduction (think: ABDUCTion) is the movement of a structure away from its midline reference point. Let the name help you out. What does “abduct” mean? When you hear on the news that a man was abducted, you know it means that someone took him away. That’s exactly what’s going on with this movement. The structure is being moved away from its midline reference point.
What is Adduction?
Adduction (think: ADDuction) occurs as the structure is ADDED back toward its midline reference point.
Let’s take a look at examples of abduction and adduction on the body.
Arm Abduction and Adduction
During arm abduction (also called shoulder abduction), the arms move away from the body’s midline. During arm adduction (or shoulder adduction), you ADD them right back toward the midline.
Finger Abduction and Adduction
Finger abduction occurs when the fingers move away from the midline reference of the hand, whereas finger adduction occurs when you add them back toward the hand’s midline reference.
When the middle finger (3rd digit), which serves as the midline reference of the hand, deviates to the away from the body, it’s called lateral abduction. When it deviates toward the body, it’s called medial abduction.
Thumb Abduction and Adduction
The thumb (pollex) is different from the fingers. Abduction of the thumb has it moving within the sagittal plane, in an anterior motion. Adduction of the thumb has it added back to the hand.
Wrist Abduction and Adduction (Ulnar Deviation & Radial Deviation)
When determining abduction and adduction of the wrist, I find that it helps to stand in the anatomical position. Abduction of the wrist has it moving away from the body’s midline, in the same direction as arm abduction. Adduction of the wrist has it going in the opposite direction, toward the body’s midline.
These movements are also referred to as radial deviation and ulnar deviation. Remember, the radius is on the thumb side, which where you check the radial pulse. So radial deviation is movement on the radial side, whereas ulnar deviation occurs on the opposite side.
Thigh Abduction and Adduction
During thigh abduction (also called hip abduction or leg abduction), the lower limb moves away from the body’s midline. During adduction of the thigh, you ADD the lower limb right back toward the body’s midline.
Toes Abduction and Adduction
When the toes move away from the midline of the foot, toe abduction occurs. Toe adduction adds them right back together.
Just like with the hand, devation of the 2nd toe away from the body’s midline is called lateral abduction, whereas movement toward the midline is called medial abduction.
Free Quiz and More Anatomy Videos
Take a free abduction and adduction quiz to test your knowledge, or review our quick abduction vs adduction video. In addition, you might want to watch our anatomy and physiology lectures on YouTube, or check our anatomy and physiology notes.