Part 1: Pectoral Girdle Flashcards
Bones of the pectoral girdle are
Scapula and clavicle
Joints of the pectoral girdle are
Sternoclavicular and acromioclavicular
Origin of pectoralis major
Clavicular head: medial 1/2 of clavicle
Sternocostal head: lateral manubrium and sternum, six upper costal cartilages and external oblique aponeurosis
Insertion of pectoralis major
lateral lip of bicipital groove of humerus and anterior lip of deltoid tuberosity
Action of pec major
Clavicular head: flexion
Sternal head: adducts and medially rotates arm
Nerve supply of pec major
Medial pectoral nerve (medial cord) and lateral pectoral nerve (lateral cord)
Pect Minor origin
Anterior aspect of ribs 3,4,5
Pect Minor insertion
Medial and upper surface of coracoid process of scapula
Pect Minor Action
Elevates ribs when scapular fixed or depresses point of shoulder
Pect Minor nerve supply
Medial pectoral nerve (medial cord) and lateral pectoral nerve (lateral cord)
Subclavius origin
Costochondral junction of 1st rib
Subclavius insertion
Subclavian groove on inferior surface of middle 1/3 of clavicle
Subclavius action
Depresses and steadies clavicle
Subclavius nerve supply
Nerve to subclavius ( C5,^ upper trunk)
Trapezius origin
Medial 1/3 of the superior nuchal line, ligamentum nuchae, spinous process and supraspinous ligaments to T12
Trapezius insertion
Upper fibres: lateral 1/3 of posterior border of clavicle, medial acromion and lateral spine of scapula
Lower fibres: medial end of scapula spine as far as deltoid tuberosity of spine of scapular
Trapezius action
Elevates and retracts scapula. Rotates scapula during abduction of arm. If scapula fixed - extends and laterally flexes neck
Trapezius nerve supply
Spinal root of accessory nerve (XI). Spinal nerve (C3,C4) for proprioception.
Latissimus Dorsi Origin
All thoracic spines and supraspinous ligaments from T7 down and L/S spines via lumbar fascia.
Posterior 1/3 of iliac crest and lower 4 ribs
Latissimus Dorsi insertion
Floor of bicipital groove of humerus after spiralling around teres major
Latissimus Dorsi action
Extends, adducts and medially rotates arm. Costal attachments help with deep inspiration/exp.
Latissimus Dorsi nerve supply
Thoracodorsal nerve from posterior cord
Rhomboid major origin
Spines of T2-T5 an supraspinous ligaments
Rhomboid major insertion
Lower 1/2 of posterior medial border of scapula at level of the spine
Rhomboid major action
Retracts scapula and rotates to rest position
Rhomboid major nerve supply
Dorsal scapula nerve (C5) from root
Rhomboid minor origin
Lower ligamentum nchae, spines of C7/T1
Rhomboid minor insertion
Small area of posteromedial border of scapula at level of spine
Rhomboid minor action
Retracts scapula and rotates to rest position
Rhomboid minor nerve supply
Dorsal scapula nerve (C5) from root
Levator scapulae origin
Posterior tubercle of transverse process of C1-C4
Levator scapulae insertion
upper part of medial border of scapula
Levator scapulae action
Raises medial border of scapula
Levator scapulae nerve supply
dorsal scapula nerve and anterior 1’ rami of C3/C$
Serratus anterior origin
Upper 8 ribs and anterior intercostal membranes from midclavicular line
Serratus anterior insertion
Inner medial border of scapula
1&2 - upper angle
3&4 - costal margin
5-8 - inferior angle
Serratus anterior action
laterally rotates and protracts scapula
Serratus anterior nerve supply
Long thoracic nerve with:
1-2: C5
3-4: C6
5-8: C7
