Superficial Back Muscles

Question 1

Trapezius

[nerve injury= drooping of scapula]

Answer 1

o- occipital bone, ligamentum nuchae, C7-T12
i- lateral 1/3 clavicle, acromion, spine of scapula
n- CN XI motor, C3 C4 sensory
b- superficial branch of transverse cervical artery
a- holds upper limb to trunk, adducts scapula (middle), raises scapula (upper), depresses scapula (lower), rotates scapula so the inferior angle moves laterally

Question 2

Latissimus Dorsi

[nerve injury= unable to raise trunk with upper limbs during climbing]

Answer 2

o-spinous process of lower 6 thoracic vertebrae, thoracolumbar fascia, iliac crest and lower 3-4 ribs
i- intertubercular groove of humerus
n- thoracodorsal nerve [C6, C7, C8]
b- thoracodorsal artery
a- extend arm, rotates humerus medially at shoulder, adducts (powerful adductor)

Question 3

Triangle of Auscultation

Answer 3

Bounded by:
trapezius
latissimus dorsi
medial border of scapula

Question 4

Levator Scapulae

Answer 4

o-transverse process of C1-C4
i- superior angle of scapula, medial border of scapula
n- dorsal scapular n C5, and C3 C4
b- dorsal scapular artery (branch of axillary a), deep branch of transverse cervical artery
a- elevate scapula, rotate scapula to move glenoid cavity inferiorly

Question 5

Rhomboid minor

Answer 5

o- spines of lower cervical C7 and T1-T5
i- medial border of scapula
n- dorsal scapular nerve [injury= not able to adduct scapula] C5
b- dorsal scapular artery
a- adduct scapula, rotate scapula so glenoid cavity moves inferiorly

Question 6

Serratus posterior superior

Answer 6

o- ligamentum nuchae, spines of C7 to T3
i- 2nd to 4th ribs
n- T1-T3
a- elevates ribs

Question 7

Serratus Posterior Inferior

Answer 7

o- T11- L2 vertebral spines
i- lower 4 ribs
n- T9-T12
a- respiration by holding ribs steady when diaphragm moves up