Posterior Shoulder and Posterior Compartment of Arm

Question 1

Deltoid (Anterior, Lateral, Posterior)
Blood supply:
Nerve Supply:
Action:

Answer 1

Deltoid (Anterior, Lateral, Posterior)
Blood supply: Posterior circumflex humoral artery
Nerve Supply: Axillary nerve (c5-c6)
Action: Anterior (medially rotate, adduct arm), Lateral (Abduct arm), Posterior (Laterally rotate, extend, adduct arm)

Question 2

Teres major
Blood supply:
Nerve Supply:
Action:

Answer 2

Teres major
Blood supply: Circumflex scapular artery
Nerve Supply: Lower subscapular (c5-c7)
Action: Medially rotate, extend, adduct arm

Question 3

Teres minor
Blood supply:
Nerve Supply:
Action:

Answer 3

Teres minor
Blood supply: Circumflex scapular artery + posterior circumflex humeral artery
Nerve Supply: Axillary nerve
Action: Laterally adduct (weak), rotate arm)

Question 4

Infraspinatus
Blood supply:
Nerve Supply:
Action:

Answer 4

Infraspinatus
Blood supply: Circumflex scapular artery + suprascapular artery
Nerve Supply: Suprascapular nerve (c4-c6)
Action: Laterally rotate arm

Question 5

Supraspinatus
Blood supply:
Nerve Supply:
Action:

Answer 5

Supraspinatus
Blood supply: Suprascapular artery
Nerve Supply: Suprascapular nerve (c4-c6)
Action: Abduct the arm

Question 6

Triceps (long head, lateral head, medial head)
Blood supply:
Nerve Supply:
Action:

Answer 6

Triceps (long head, lateral head, medial head)
Blood supply: Deep brachial artery
Nerve Supply: Radial nerve
Action: Long head –> extend, adduct arm + extend forearem
Lateral and medial heads –> extend forearm