Upper Extremity: Shoulder Region

Question 1

Scapulohumeral (intrinsic shoulder) muscles function

Answer 1

• Function directly on glenohumeral joint

Question 2

Scapulohumeral (intrinsic shoulder) muscles

Answer 2

• Deltoid
• Teres major
• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis
• Coracobrachialis can be part of this group

Question 3

Rotator cuff muscles

Answer 3

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

Question 4

Deltoid

Answer 4

• Forms the round contour of the shoulder
• Named based on shape (Greek Δ)
• 3 separate fiber groups that can act separately

Question 5

Deltoid proximal attachment

Answer 5

• Lateral 1/3 of clavicle

- Acromion and spine of the scapula

Question 6

Deltoid distal attachment

Answer 6

• Deltoid tuberosity of humerus

Question 7

Deltoid innervation

Answer 7

• Axillary nerve (C5,6)

Question 8

Deltoid function (shoulder joint)

Answer 8

• Flexion and medial rotation
• Extension and lateral rotation
• Abduction (after 15⁰)

Question 9

Rotator cuff muscles (SITS muscles)

Answer 9

• Form a musculotendinous cuff around the glenohumeral joint
• Important stabilizers of the GH joint
• Reinforce joint capsule
• Help keep the humeral head approximated to the glenoid fossa

Question 10

Supraspinatus proximal attachment

Answer 10

• Supraspinous fossa of scapula

Question 11

Supraspinatus distal attachment

Answer 11

• Greater tubercle of humerus

Question 12

Supraspinatus innervation

Answer 12

• Suprascapular nerve (C5,6)

Question 13

Supraspinatus function

Answer 13

• Ontiates/assists with arm abduction

- GH stabilizer

Question 14

Infraspinatus proximal attachment

Answer 14

• Infraspinous fossa of scapula

Question 15

Infraspinatus distal attachment

Answer 15

• Greater tubercle of humerus

Question 16

Infraspinatus innervation

Answer 16

• Suprascapular nerve (C5,6)

Question 17

Infraspinatus function

Answer 17

• Lateral rotator of arm

- GH stabilizer

Question 18

Teres minor proximal attachment

Answer 18

• Posterior surface of inferior angle

Question 19

Teres minor distal attachment

Answer 19

• Greater tubercle of humerus

Question 20

Teres minor innervation

Answer 20

• Axillary nerve (C5,6)

Question 21

Teres minor function

Answer 21

• Lateral rotator of arm

- GH stabilizer

Question 22

Subscapularis proximal attachment

Answer 22

• Subscapular fossa

Question 23

Subscapularis distal attachment

Answer 23

• Lesser tubercle of humerus

Question 24

Subscapularis innervation

Answer 24

• Upper and lower subscapular nerve (C5-7)

Question 25

Subscapularis function

Answer 25

- Medial rotation of arm | - GH stabilizer

Question 26

Rotator cuff injuries

Answer 26

- Trauma can rupture/tear one or more of the tendons - Supraspinatus is most commonly injured - Difficulty initiating abduction

Question 27

Repetitive rotator cuff use can cause

Answer 27

- Recurrent inflammation leading to degenerative tendonitis - Overhead sports - Impingement on the coracoacromial arch - Limited blood supply: susceptible to degeneration

Question 28

Rotator cuff degeneration

Answer 28

- Increases susceptibility to tendon rupture

Question 29

Teres major

Answer 29

- Along with latissimus dorsi, forms posterior axillary fold

Question 30

Teres major proximal attachment

Answer 30

- Posterior aspect of inferior angle of scapula

Question 31

Teres major distal attachment

Answer 31

- Medial lip of intertubercular sulcus

Question 32

Teres major innervation

Answer 32

- Lower subscapular nerve (C5-7)

Question 33

Teres major function

Answer 33

- Adducts and medially rotates arm

Question 34

Quadrangular space boundaries

Answer 34

- Superior: inferior margin teres minor - Inferior: superior margin teres major - Medial: lateral margin of long head of triceps brachii - Lateral: surgical neck of humerus

Question 35

Quadrangular space content

Answer 35

- Axillary nerve | - Posterior humeral circumflex artery and vein

Question 36

Triangular space boundaries

Answer 36

- Superior: inferior margin teres minor - Inferior: superior margin teres major - Lateral: medial margin of long head of triceps brachii

Question 37

Triangular space content

Answer 37

- Circumflex scapular artery and vein

Question 38

Triangular interval (triceps hiatus) boundaries

Answer 38

- Superior: inferior margin of teres major - Medial: lateral margin of long head of triceps brachii - Lateral: shaft of humerus

Question 39

Triangular interval (triceps hiatus) content

Answer 39

- Radial nerve | - Deep artery and vein of the arm (profunda brachii artery and vein)

Question 40

Subscapular foramen

Answer 40

- Formed by suprascapular notch and superior transverse scapular ligament - The suprascapular nerve passes through the foramen - The suprascapular artery and vein pass above the ligament, NOT through the foramen

Question 41

Suprascapular nerve location

Answer 41

- Passes through subscapular foramen

Question 42

Suprascapular artery and vein location

Answer 42

- Pass above the transverse scapular ligament, NOT through the foramen

Question 43

Base of scapular spine level

Answer 43

- T3 vertebral level

Question 44

Inferior angle of scapula level

Answer 44

- T7 vertebral level