Shoulder Complex

Question 1

Pectoralis Major

Answer 1

Attachments:
Clavicular head —> medial 1/2 of clavicle.
Sternocostal head —> ant. sternum, CC 1-6.
Intertubercular sulcus.

Actions: adducts & medially rotates humerus, draws scapula anteriorly and inferiorly. C head flexes and SC head extends from flexed.

Innervation: lat. med. pec nerves.

Question 2

Pectoralis Minor

Answer 2

Attachments:
Ribs 3-5 near CC.
Coracoid process.

Actions: stabilises scap (draw ant. & inf.).

Innervation: med. pec. nerve.

Question 3

Subclavius

Answer 3

Attachments:
Junction of rib 1 & CC 1.
Inferior surface of middle 1/3 of clavicle.

Actions: anchors and depresses.

Innervation: nerve to SC.

Question 4

Serratus Anterior

Answer 4

Attachments:
Lateral aspect of ribs 1-8.
Medial border of scap.

Action: protract scap. and rotate superiority, hood scap. to thorax.

Innervation: LT nerve.

Question 5

Trapezius

Answer 5

Attachments:
Superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12.

Action: lower depress, upper elevate & middle retract scap. Upper/lower together rotate the glenoid cavity superiorly.

Innervation: CN XI & C3-4.

Question 6

Latissimus Dorsi

Answer 6

Attachments:
Spinous processes of T7-12, TL fascia, iliac crest, ribs 9-12.
Intertubercular sulcus.

Action: extends, adducts & medially rotates humerus.

Innervation: thoracodorsal nerve.

Question 7

Levator Scapulae

Answer 7

Attachments:
TP of C1-4.
Med. border of scap.

Actions: elevate scap and rotate inferiorly.

Innervation: dorsal scapular nerve, C3-4.

Question 8

Rhomboids

Answer 8

Attachments:
C7 & T1 (minor), T2-5 (major).
Medial border of scap.

Actions: retract scapula and rotate superiorly.

Innervation: dorsal scapula nerve

Question 9

Deltoid

Answer 9

Attachments:
Lat. 1/3 of clavicle, AC, spine of scap.
Deltoid tuberosity.

Action: ant. fibres flex & medially rotate arm, post. fibres extend and laterally rotate. All fibres active in abduction.

Innervation: axillary nerve.

Question 10

Supraspinatus

Answer 10

Attachments:
SP fossa.
GT of humerus.

Actions: initiates abduction, apposition.

Innervation: suprascapular nerve.

Question 11

Infraspinatus & Teres m

Answer 11

Attachments:
Infraspinous fossa (infra)
Lateral border of scap (m)
GT of humerus.

Actions: lat. rotation of humerus. Apposition.

Innervation:
Suprascapular nerve (infra)
Axillary nerve (m)

Question 12

Subscapularis

Answer 12

Attachments:
Sub scap. fossa.
LT is humerus.

Action: medial rotation of humerus, apposition.

Innervation: U&L subscap. nerves.

Question 13

Teres M

Answer 13

Attachments:
Inf. angle of scap.
Intertubercular sulcus.

Action: adducts and medially rotates.

Innervation: L subscap. nerve