Shoulder Complex Flashcards
Origin of Pectoralis Major
Clavicle,
sternum
upper six costal cartilages
Insertion of Pectoralis Major
Lateral lip of the bicipital groove of humerus
Innervation of Pectoralis Major
Medial and lateral pectoral nerves form brachial plexus
Action of Pectoralis Major
Adducts arm and rotates it medially;
clavicular fibers also flex arm
Origin of Pectoralis Minor
3rd, 4th and 5th ribs
Insertion of Pectoralis Minor
Coracoid process of scapula
Innervation of Pectoralis Minor
Medial pectoral nerve from the brachial plexus
Action of Pectoralis Minor
Depresses point of shoulder;
if the scapula is fixed, it elevates the ribs of origin
Origin of Subclavius
First costal cartilage
Insertion of Subclavius
Clavicle
Innervation of Subclavius
Nerve to subclavius from upper trunk of brachial plexus
Action of Subclavius
Depresses the clavicle and steadies
this bone during movements of the shoulder girdle
Origin of Serratus Anterior
Upper eight ribs
Insertion of Serratus Anterior
Medial border and
inferior angle of the scapula
Innervation of Serratus Anterior
Long thoracic nerve
Action of Serratus Anterior
Draws the scapula forward around the
thoracic wall; rotates the scapula
Origin of Trapezius
Occipital bone,
ligamentum nuchae,
spine of 7th cervical
vertebra, spines of all
thoracic vertebra
Insertion of Trapezius
Upper fibers into
lateral third of
clavicle; middle and
lower fibers into
acromion and spine
of the scapula
Innervation Trapezius
Spinal part of accessory nerve (motor) and C3 and C4 (sensory)
Action of Trapezius
Upper fibers elevate the scapula;
middle fibers pull the scapula medially;
lower fibers pull medial border of the scapula downward
Origin of Latissimus Dorsi
Iliac crest, lumbar fascia, spines of
lower six thoracic vertebrae, lower three or four ribs, and inferior angle of the scapula
Insertion of Latissimus Dorsi
Floor of bicipital
groove of humerus
Innervation of Latissimus Dorsi
Thoracodorsal nerve
Action of Latissimus Dorsi
Extends, adducts
and medially rotates
the arm