The Back Flashcards
What are intrinsic back muscles?
Also called “true” back muscles, these muscles start and end in the back. They help maintain posture and move the vertebral column.
What are extrinsic back muscles?
“Superficial” back muscles that connect the upper extremities to the trunk. They are involved in upper limb movement and respiration.
Name the landmarks of the back.
1: Spine of C7
2: Spine of T7 at the inferior angle of scapula
3: Spine of L4 to the iliac crest
Trapezius
Extrinsic
Innervation: Spinal Accessory Nerve (CN XI)
Blood Flow: Transverse Cervical Artery
Action: Elevates, retracts and rotates scapula
Levator Scapulae
Extrinsic
Innervation: Dorsal Scapular Nerve
Blood Flow: Dorsal Scapular Artery
Action: Elevates scapula medially
Rhomboideus Major
Extrinsic
Innervation: Dorsal Scapular Nerve
Blood Flow: Dorsal Scapular Artery
Action: Fixes scapula to thoracic wall and retracts and rotates it to depress glenoid cavity
Rhomboideus Minor
Extrinsic
Innervation: Dorsal Scapular Nerve
Blood Flow: Dorsal Scapular Artery
Action: Fixes scapula to thoracic wall and retracts and rotates it to depress glenoid cavity
Serratus Anterior
Not a back muscle Innervation: Long Thoracic Nerve Blood Flow: Lateral Thoracic Artery Action: Protracts and rotates scapula and holds it against thoracic wall -> Injury causes "winged scapula"
Serratus Posterior Superior
Intrinsic
Innervation: Ventral rami of upper thoracic nerves
Blood Flow: Posterior Intercostal arteries
Action: Elevates ribs
Serratus Posterior Inferior
Intrinsic
Innervation: Ventral rami of lower thoracic nerves
Blood Flow: Posterior Intercostal arteries
Action: Depresses ribs
Erector Spinae
Intrinsic
Innervation: Dorsal rami of each region
Blood Flow: Extended network throughout the spine
Action: Extends and laterally bends vertebral column and head
Splenius Capitis
Innervation: Dorsal rami of cervical nerves
Blood Flow: Descending branch of occipital artery
Action: Extends head
Splenius Cervicus
Innervation: Dorsal rami of cervical nerves
Blood Flow: Descending branch of occipital artery
Action: Extends head
Rectus Capitis Posterior Major
Innervation: Suboccipital nerve
Blood Flow: Vertebral artery
Action: Extends and rotates head to same side
Rectus Capitis Posterior Minor
Innervation: Suboccipital nerve
Blood Flow: Vertebral artery
Action: Extends head
Obliquus Capitis Superior
Innervation: Suboccipital nerve
Blood Flow: Vertebral artery
Action: Extends and bends head laterally
Obliquus Capitis Inferior
Innervation: Suboccipital nerve
Blood Flow: Vertebral artery
Action: Rotates atlas to turn face to same side
Latissimus Dorsi
Extrinsic
Innervation: Thoracodorsal nerve
Blood Flow: Thoracodorsal artery
Action: Extends, adducts, and medially rotates humerus
Triangle of Auscultation
Bounded by trapezius, latissimus dorsi, scapula
Suboccipital Triangle
Bounded by rectus capitis posterior major, obliquous capitis superior and obliquous capitis inferior.
Triangular Space
Bounded by teres major, teres minor, long head of triceps.
Quadrangular Space
Bounded by teres major, teres minor, long head of triceps, humerus.
Lumbar Triangle
Bounded by latissimus dorsi, external abdominal oblique, ilium.
Ilium
Largest bone of the pelvis
