Week 8 Muscles of the Back PALP edit

  1. Latissimus Dorsi  
    (superficial muscle of the back)
    • O: Iliac crest, Thoraco-lumbar (T/L) fascia, SP's of last 6 thoracic vertebrae and last 3-4 ribs 
    • F.D: superior lateral
    • Insertion: Floor of the intertubercular groove
    • Action: Extension, adduction and medial rotation of the humerus
    • Nerve: Thoracodorsal nerve
    • Special: Broadest muscle of the back

    O and I switch then the action is that the body raises towards the arms (chin up).Thin, superficial and ascends the side of the trunk.Image Upload 1
  2. Trapezius
    (Superficial muscle of the back)
    • O: EOP, medial 1/3rd superior nuchal
    • line, nuchal ligament and SP’s of C7 to T12 

    • F.D:  upper - inferior lateral . middle - lateral
    • lower - superior lateral

    • I: Lateral 1/3 of clavicle, acromion
    • and spine of scapula

    • A: Upper fibers elevate, middle
    • fibers retract and inferior fibers depress the scapula

    N: Spinal accessory nerve (CN 11)

    Image Upload 2
  3. Rhomboid Minor
    (superficial muscle of the back)
    O: nuchal ligament and SP’s of C7-T1                                               

    F.D: inferior lateral

    • I: Medial border of scapula at the
    • spine of the scapula

    • A: Adducts (retracts scapula), fixes
    • scapula to thoracic wall (assists serratus anterior)

    N: Dorsal scapular nerve 

    Image Upload 3
  4. Rhomboid Major
    (superficial muscle of the back)
    O: SP of T2-T5 

    FD:inferior lateral

    • I: Medial border of scapula between
    • spine and inferior angle

    • A: Adducts (retracts scapula), fixes
    • scapula to thoracic wall (assists serratus anterior)

    N : Dorsal Scapular nerve

    • Image Upload 4
  5. Levator Scapulae
    (superficial muscle of the back)
    • O: Posterior tubercle tubercles of TVP’s 
    • C1-C4

    F.D: inferior posterior                

    • I: Medial border of scapula superior
    • to the root of spine of scapula

    • A: Elevates scapula and performs
    • downward rotation of the scapula

    N: Dorsal scapular nerve

    S: deep to upper fibers of trapezius

    Image Upload 5
  6. Pectoralis Major
    (anterior trunk muscle)
    • O:  
    • Clavicular Head:Anterior surface of                                                           
    • the medial ½ of the clavicle                                                  

    • Sternal Head: Anterior sternum, superior                                                  
    • 6 costal cartilages and aponeurosis of                                                          
    • the external oblique abdominal muscles

    F.D: lateral

    • I: Lateral lip of the
    • inter-tubercular groove                                                  
    • of the humerus

    • A: Adduct, internal rotation of
    • the humerus and extends the arm from 90                                             
    • degrees of flexion (The clavicular head                                                
    • alone will also aid in flexion of the arm)

    • N: Lateral and medial pectoral nerve
    • Image Upload 6
  7. Pectoralis Minor
    (Anterior trunk muscles)
    • O: Ribs 3-5 close to their costal
    • cartilage

    F.D: superior lateral

    I: Coracoid process of the scapula

    • A: Stabilize the scapula by drawing
    • it inferiorly and anteriorly against the thoracic wall

    N: Medial pectoral nerve

    • Image Upload 7
  8. Subclavius
    • O: Junction of first rib and it’s
    • cartilage

    F.D: superior lateral

    • I: Inferior aspect of clavicle (middle
    • third)

    • A: Draws clavicle medially and
    • anteriorly

    N: Nerve to Subclavius

    • Image Upload 8
  9. Serratus Anterior
    (superfical trunk muscle)
    • O: External surfaces of the lateral
    • part of the ribs 1-8

    F.D: posterior superior

    • I: Anterior surface of the medial
    • border of scapula

    • A: Protracts the scapula and holds it
    • against the thoracic wall, upward rotation of scapula

    N: Long thoracic nerve

    • Image Upload 9
  10. External Intercostal Muscle
    • O: Inferior border of the superior
    • ribs

    F.D:Anterior inferior

    • I: Superior border of the inferior
    • ribs

    • A: Elevates the ribs during
    • inspiration

    N: Intercostal nerves 

    Image Upload 10

    •This muscle has an anteroinferior fiber direction (“hands in my pocket”)

    •Medial to the costochondral junction, this muscle becomes the external intercostal membrane
  11. Internal Intercostal
    • O: Superior border of the inferior
    • rib

    F.D: anterior superior

    • I: Inferior border of the superior
    • rib

    • A: Depress the ribs during forced
    • expiration

    N: Intercostal nerves

    Image Upload 11

    • •This muscle lies deep to the
    • external intercostal muscle

    • •This muscle has a anterior-superior
    • direction

    • •Posteriorly from the angle of the
    • rib (to the tubercle) this muscle becomes the internal intercostal membrane
  12. Thoracic Diaphragm
    • O:
    • Sternal attachments: internal aspect of the xiphoid process

    • Costal attachments: Costal
    • cartilages of ribs 6 – 10 and ribs 10-12

    Lumbar attachment: lumbar vertebral bodies of L1-L3(4) on the right and L1-L2(3) on the left

    F.D: central

    I: Central tendon

    A: Primary muscle of inspiration

    I: C3,C4,C5 ventral/anterior primary rami

    SS: Its the only muscle that inserts onto itself

    • Image Upload 12
Card Set
Week 8 Muscles of the Back PALP edit
Intro ( week 8)