Origins, Insertions, Actions, Innervations, Blood Supply Flashcards
Trapezius Origin
- External Occipital Protuberance
- Medial 1/3 of superior nuchal line
- Ligamentum nuchae
- Spinous processes of C7-T12
Trapezius Insertion
- Superior: Lateral 1/3 of clavicle
- Middle: Spine and acromion of scapula
- Inferior: Base of spine of scapula
Trapezius Innervation
- Spinal accessory nerve
- Ventral rami of 3rd and 4th cervical nerves
- CN XI and C3/C4 fibers form subtrapezial plexus on deep surface of muscle
Trapezius Blood Supply
Superficial branch of transverse cervical artery
Trapezius Actions
- Raises, retracts, and rotates scapula
- Bilateral contraction of superior fibers extends head
- Unilateral contraction of upper fibers laterally flexes head and cervical vertebrae
Latissimus Dorsi Origin
- Spinous processes of T7-T12
- All lumbar and sacral vertebrae (SPs)
- Posterior part of iliac crest
- From lower 3-4 ribs via muscular slips that interdigitate with external oblique muscle
Latissimus Dorsi Insertion
- Crest of lesser tubercle
- Floor of bicipital groove of humerus
Latissimus Dorsi Innervation
Thoracodorsal nerve (posterior cord of brachial plexus, C6-C8 fibers)
Latissimus Dorsi Blood Supply
Thoracodorsal artery (branch of subscapular artery)
Latissimus Dorsi Action
Extension, medial rotation, and adduction of arm
Levator Scapulae Origin
Posterior tubercles of TPs of C1-C3/C4
Levator Scapulae Insertion
Medial border of scapula from superior angle to base of spine
Levator Scapulae Innervation
- Ventral rami C3, C4 from deep branches of cervical plexus
- Twig from dorsal scapular nerve (C5)
Levator Scapulae Blood Supply
Deep branch of transverse cervical artery
Levator Scapulae Action
- Elevates and retracts scapula with trapezius
- Laterally flexes cervical vertebrae column when scapula is fixed
Rhomboid Minor Origin
- Lower part of ligamentum nuchae
- Spinous processes of C7 and T1
Rhomboid Minor Insertion
Medial border of scapula at base of spine
Rhomboid Minor Innervation
Dorsal scapular nerve (C4, C5)
Rhomboid Minor Blood Supply
Deep branch of transverse cervical artery
Rhomboid Minor Action
- Elevates medial border of scapula
- Retracts scapula
- Rotation of scapula (downwards)
Rhomboid Major Origin
Spinous processes of T2-T5
Rhomboid Major Insertion
Medial border of scapula between base of spine and inferior angle
Rhomboid Major Innervation
Dorsal scapular nerve (C4, C5)
Rhomboid Major Blood Supply
Deep branch of the transverse cervical artery
Rhomboid Major Action
- Elevates medial border of scapula
- Retracts scapula
- Rotation of scapula (downwards)
Serratus Posterior Superior Origin
- Lower end of ligamentum nuchae
- Spinous processes of C7-T2/3
Serratus Posterior Superior Insertion
Ribs 2-5 lateral to angle
Serratus Posterior Superior Innervation
First four intercostal nerves (ventral Rami of first four thoracic nerves)
Serratus Posterior Superior Blood Supply
- Highest intercostal artery
- Posterior intercostal arteries
Serratus Posterior Superior Action
Elevates upper ribs during inspiration
Serratus Posterior Inferior Origin
SPs of T10-L2
Serratus Posterior Inferior Insertion
Lower 3-4 ribs lateral angles
Serratus Posterior Inferior Innervation
Lowest 4 intercostal nerves (ventral rami of lower thoracic)
Serratus Posterior Inferior Blood Supply
Posterior intercostal arteries