Isolated and Integrated muscle functions

Terms	Definitions
Transverse abdominis	Lies deep to the internal and external abdominal and works with them to compress the abdomen.
Diaphragm	Large, flat muscle at the bottom of the chest cavity that helps with breathing
Superficial Erector Spinae; Illiocostalis, longissimus, and spinalis	The erector group which lies lateral and superficial to the multifidus allow for extension and posterior translation when the muscles are contracted bilaterally.
Quadratus Lumborum	Arises from the iliac crest which extends between the transverse processes of the 5th lumbar vertebra
Multifidus	Acts primarily as a sagital rotator
Latissimus dorsi	A strong extensor, internal rotator, and adductor of the glenohumeral joint
Serratus Anterior	Protracts the scapula and is active in reaching and pulling
Rhomboids	Adduct the scapula and rotate downward
Lower Trapezius	Causes scapula depression
Middle Trapezius	Causes scapula retraction
Upper Trapezius	Cause upward motion of the scapula
Pectoralis Major	The anterior muscles of the shoulder joint. A prime mover inadduction, horizontal adduction, and internat rotation of the humerus.
Pectoralis Minor	Causes protraction, downward rotation, and depression of the scapula
Anterior Deltoid	Responsible for shoulder flexion, horizontal adduction, and internal rotation of the glenohumeral
Middle Deltoid	A powerful abductor of the glenohumeral joint
Posterior Deltoid	Glenohumeral extension, horizontal abduction, and external rotation oppose those of the anterior deltoid.
Teres Major	Extends, adducts and medially rotate the humerus at the shoulder joint.
Teres Minor	Inserts on the humerus and extends the humerus.
Infraspinatus	Rotates the shoulder laterally
Subscapularis	Acts to rotate the humerus medialy and stabilizes the shoulder joint
Supraspinatus	Inserts on the humerus and abducts the shoulder
Biceps Brachii	Affects the shoulder, elbow and radioulnar joints
Triceps Brachii	The chief extensor of the elbow; in addition the long head stabilizes the shoulder joint
Brachioradialis	Flexes the forearm at the elbow
Brachialis	The strongest flexor of the elbow.
Levator Scapulae	Produces elevation and downward rotation of scapula and also act on the neck
Sternocleidomastoid	Contraction of one side: laterally flexes neck, rotates head to opposite side; Contraction of both sides together: flexes neck
Scalenes	flex neck (when 1st rib is fixed); elevate 1st and 2nd ribs during forced inhalation when neck is fixed
Longus Colli	Acts to flex and rotate the neck
Longus Capitis	Inserts on the occipital bone to flex the atlanto-occipital joint