Pectoral And Shoulder Muslces Flashcards
(17 cards)
Definition of origin
Attachment site of muscle that does not move during contraction
Definition of insertion
Attachment site of muscle that does move during contraction
Definition of innervation
Nerve distribution
Definition of action
Motion produced by muscle contraction
Definition of agonist
Muscle or group most directly related to the movement
Definition of antagonist
Muscle or group whose action is opposite to the agonist’s action.
Definition of synergist
Two or more muscles that work together to execute a motion
Fusifrom
Parallel
Unipennate
One side
Bipennate
Two sides
Multipennate
Many angles
Trapezius
N: Accessory ( cranial nerve 11)
A: upward rotation of the lateral scapular border ( upper and lower), scapular elevation (upper), scapular retraction ( middle), scapular depression ( lower)
Latissimus Dorsi
N: Thoracodorsal Nerve ( C6, C7, C8)
A: extends, adducts, internally rotates the humerus
Levator scapulae
N: anterior rami spinal nerves ( C3-C4) dorsal scapular nerve C5
A: scapular elevation, inferiorly rotates scapular
Rhomboid minor
Superior to the rhomboid major
N: Dorsa scapular nerve (C4-C5)
A: Retracts and elevates scapula
Rhomboid Major
Inferior to the rhomboid minor
N: Dorsal Scapular ( C4-C5)
A: retracts and elevates the scapula, plays a role in downward rotation of the scapula.
Pectoralis Major
O: Clavicular head / Sternocostal end
N: lateral and medial pectoral nerves. Clavicular head (C5, C6), Sternocostal (C6,C7,C8,T1)
A: flexion, adduction,
medially rotates the glenohumeral joint.
Clavicular head flexes the extended arm,
Sternocostal head extends the flexed arm
