Pronation
Encyclopedia
In anatomy
, pronation is a rotational movement of the forearm
at the radioulnar joint, or of the foot
at the subtalar
and talocalcaneonavicular joints. For the forearm, when standing in the anatomical position, pronation will move the palm of the hand from an anterior-facing position to a posterior-facing position without an associated movement at the shoulder
(glenohumeral joint
). This corresponds to a counterclockwise twist for the right forearm and a clockwise
twist for the left (when viewed superiorly). For the foot, pronation will cause the sole of the foot to face more laterally than when standing in the anatomical position. Pronation is the opposite of supination
.
This action is performed by pronator quadratus
and pronator teres muscle
. Brachioradialis
puts the forearm into a midpronated/supinated position from either full pronation or supination.
Pronation of the forearm should not be confused with medial rotation of the shoulder. When standing in the anatomical position, medial rotation of the shoulder can perform part of the movement to change the palm from facing ventrally to dorsally. Pronation of the forearm occurs at the radioulnar joint so such a movement does not constitute it. To isolate medial rotation in the shoulder from pronation of the forearm one can stand with one's elbows tucked against the trunk, with the elbows flexed to 90 degrees with the forearms pointing directly in front of the body with the palms of the hands facing upwards. Keeping one's elbows tucked at the sides, the act of moving one's forearms so that the palms are facing downwards is pronation of the forearm.
, achilles tendinitis, posterior tibial tendinitis, Piriformis syndrome
, and plantar fasciitis
.
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
, pronation is a rotational movement of the forearm
Forearm
-See also:*Forearm flexors*Forearm muscles...
at the radioulnar joint, or of the foot
Foot
The foot is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws...
at the subtalar
Subtalar joint
In human anatomy, the subtalar joint, also known as thetalocalcaneal joint, is a joint of the foot. It occurs at the meeting point of the talus and the calcaneus.-Motion:...
and talocalcaneonavicular joints. For the forearm, when standing in the anatomical position, pronation will move the palm of the hand from an anterior-facing position to a posterior-facing position without an associated movement at the shoulder
Shoulder
The human shoulder is made up of three bones: the clavicle , the scapula , and the humerus as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder make up the shoulder joints. The major joint of the shoulder is the glenohumeral joint, which...
(glenohumeral joint
Glenohumeral joint
The glenohumeral joint, or shoulder joint, is a multiaxial synovial ball and socket joint and involves articulation between the glenoid fossa of the scapula and the head of the humerus...
). This corresponds to a counterclockwise twist for the right forearm and a clockwise
Clockwise
Circular motion can occur in two possible directions. A clockwise motion is one that proceeds in the same direction as a clock's hands: from the top to the right, then down and then to the left, and back to the top...
twist for the left (when viewed superiorly). For the foot, pronation will cause the sole of the foot to face more laterally than when standing in the anatomical position. Pronation is the opposite of supination
Supination
Supination is a position of either the forearm or foot; in the forearm when the palm faces anteriorly, or faces up . Supination in the foot occurs when a person appears "bow-legged" with their weight supported primarily on the anterior of their feet.The hand is supine in the anatomical position...
.
Pronation of the forearm
This action is performed by pronator quadratus
Pronator quadratus
Pronator quadratus is a square shaped muscle on the distal forearm that acts to pronate the hand.As it is on the anterior side of the arm, it is innervated by a branch of the median nerve, the anterior interosseous nerve...
and pronator teres muscle
Pronator teres muscle
The pronator teres is a muscle of the human body that, along with the pronator quadratus muscle, serves to pronate the forearm .-Structure:...
. Brachioradialis
Brachioradialis
Brachioradialis is a muscle of the forearm that acts to flex the forearm at the elbow. It is also capable of both pronation and supination, depending on the position of the forearm...
puts the forearm into a midpronated/supinated position from either full pronation or supination.
Pronation of the forearm should not be confused with medial rotation of the shoulder. When standing in the anatomical position, medial rotation of the shoulder can perform part of the movement to change the palm from facing ventrally to dorsally. Pronation of the forearm occurs at the radioulnar joint so such a movement does not constitute it. To isolate medial rotation in the shoulder from pronation of the forearm one can stand with one's elbows tucked against the trunk, with the elbows flexed to 90 degrees with the forearms pointing directly in front of the body with the palms of the hands facing upwards. Keeping one's elbows tucked at the sides, the act of moving one's forearms so that the palms are facing downwards is pronation of the forearm.
Pronation of the foot
The pronated foot is one in which the heel bone angles inward and the arch tends to collapse. (A "knock-kneed" person has overly pronated feet.) It flattens the arch as the foot strikes the ground in order to absorb shock when the heel hits the ground, and to assist in balance during mid-stance. If habits develop, this action can lead to foot pain as well as knee pain, shin splintsShin splints
Shin splints or medial tibial stress syndrome refers to pain along or just behind the shins with sports that apply extreme pressure to the legs, such as gymnastics...
, achilles tendinitis, posterior tibial tendinitis, Piriformis syndrome
Piriformis syndrome
Piriformis syndrome is a neuromuscular disorder that occurs when the sciatic nerve is compressed or otherwise irritated by the piriformis muscle causing pain, tingling and numbness in the buttocks and along the path of the sciatic nerve descending down the lower thigh and into the leg...
, and plantar fasciitis
Plantar fasciitis
Plantar fasciitis is a painful inflammatory process of the plantar fascia, the connective tissue on the sole of the foot.Longstanding cases of plantar fasciitis often demonstrate more degenerative changes than inflammatory changes, in which case they are termed plantar fasciosis. The suffix...
.
See also
- capitulum of the humerusCapitulum of the humerusIn human anatomy of the arm, the lateral portion of the articular surface of the humerus consists of a smooth, rounded eminence, named the capitulum of the humerus....
- radial notchRadial notchThe radial notch of the ulna is a narrow, oblong, articular depression on the lateral side of the coronoid process; it receives the circumferential articular surface of the head of the radius....
- proximal radioulnar articulationProximal radioulnar articulationThe proximal radioulnar articulation is a trochoid or pivot joint between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament.-See also:...
- distal radioulnar articulationDistal radioulnar articulationThe distal radioulnar articulation is a pivot-joint formed between the head of the ulna and the ulnar notch on the distal radius.-Ligaments:The articular surfaces are connected together by the following ligaments:...
- annular ligamentAnnular ligamentThe anular ligament is a strong band of fibers, which encircles the head of the radius , and retains it in contact with the radial notch of the ulna....
- nursemaid's elbowNursemaid's elbowNursemaid's elbow, Babysitter's elbow or Pulled elbow is a dislocation of the elbow joint caused by a sudden pull on the extended pronated arm, such as by an adult tugging on an uncooperative child, or swinging the child by the arms during play...