Unit 1

Question 1

What are the four ROTATOR CUFF muscles?

Answer 1

“SITS”

Supraspinatus

Infraspinatous

Teres MINOR

Subscapularis

Question 2

What are the Lateral, Posterior, & Medial cords of the Brachial Plexus

named in relation to?

Answer 2

wrt the AXILLARY ARTERY

Question 3

Origin, Insertion, Innervation, Actions:

Serratus Anterior

Answer 3

Question 4

What innervates the Teres MAJOR?

What muscle group must it innervate BEFORE innervating the teres major?

Where does the Teres MAJOR insert?

Answer 4

Lower subscapular nerve (C5,C6) innervates the teres major

First, it must innervate the lower part of the subscapularis

Teres Major inserts on the medial lip of intertubercular sulcus

Question 5

What does the term “posterior triangle” refer to?

Answer 5

refers to the area of the anterolateral neck

where the ventral rami supplying the upper limb begin to form the brachial plexus

Question 6

DELTOID

What are its anterior functions?

Answer 6

Question 7

What is the Suprascapular Notch & Ligament,

and what 2 structures go underneath it, and in which direction?

Anteriorly, what is the SS Notch & Lig right next to?

Answer 7

Suprascapular nerve & Artery go through suprascapular notch & lig

from front to back

Right next to the coracoid process (anterior)

Question 8

Axilla

Name its 5 POSTERIOR boundaries

Answer 8

1. Humerus
2. Teres MAJOR
3. Latissimus Dorsi
4. Subscapularis
5. Scapula

Question 9

What INNERVATES the Deltoid?

Answer 9

The AXILLARY nerve (C5, C6), which is part of the Posterior Cord

Question 10

What muscle does Rib 1 attach to?

Answer 10

Scalene muscles

Question 11

What muscle do Ribs 3-5 attach to?

Answer 11

Pectoralis minor muscles

Question 12

Axilla

Name its 2 MEDIAL boundaries

Answer 12

1. Serratus ANTERIOR
2. Rib

Question 13

What is the medial & lateral articulations of the clavicle?

Answer 13

Medial: sternum

Lateral: acromion process of the scapula

Question 14

What part of the scapula does the humeral head articulate to?

Answer 14

glenoid fossa

Question 15

What INNERVATES the Teres Major?

Answer 15

Lower subscaspular nerve (C5, C6)

of the Posterior Cord

Question 16

The Platysma is a muscle of…

Answer 16

Facial expression

Question 17

INNERVATION: Teres MINOR

What other muscle does this nerve innervate?

Is this muscle also a rotator cuff muscle, like the Teres Minor?

Answer 17

The Axillary Nerve (C5,C6) of the Posterior Cord

This nerve also innervates the Deltoid

Unlike the Teres Minor, the deltoid is NOT a rotator cuff muscle

Question 18

Origin, Insertion, Innervation, Actions:

Pectoralis Major

Answer 18

Question 19

ORIGIN, INSERTION, FUNCTION of

SUBSCAPULARIS

Answer 19

• Origin:
  
  • Subscapular fossa of the scapula
• Insertion:
  
  • Lesser tubercle of humerus
• Function:
  
  • Medially rotates the arm at the shoulder (glenohumeral) joint
  • (i.e. INTERNAL rotation)

Question 20

Axilla

Name its 2 ANTERIOR boundaries

Answer 20

1. Pectoralis MAJOR
2. Pectoralis MINOR

Question 21

What nerves form the BRACHIAL PLEXUS?

Answer 21

Ventral rami of C5-T1

Question 22

What are the names of these parts of the sternum?

Answer 22

Question 23

Origin, Insertion, Innervation, Function:

Pectoralis Minor

Answer 23

Question 24

What is the ORIGIN, INSERTION, & FUNCTON

of the Teres MINOR?

What kind of muscle is the Teres Minor?

Answer 24

• Origin:
  
  • Middle part of the lateral border of the scapula
• Insertion:
  
  • Inferior aspect of greater tubercle (“lesser tubercle”) of humerus.
• Function:
  
  • Minor EXTERNAL rotator

The Teres MINOR is a Rotator Cuff muscle

Question 25

What are the 2 muscles in the **floor** of the posterior triangle?

Answer 25

Anterior Scalene Middle Scalene

Question 26

What INNERVATES the Subscapularis?

Answer 26

**Upper & Lower subscapular nerves (C5,C6)** of the Posterior cord (**middle** nerve is called the "thoracodorsal")

Question 27

Name these sections of the Shoulder Joint

Answer 27

Question 28

What INNERVATES the ## Footnote ****_SUPRA_**spinatus & **_INFRA_**spinatus?**

Answer 28

**Suprascapular nerve** on the Superior Trunk

Question 29

**DELTOID** What are its **posterior** functions?

Answer 29

Question 30

What big vein is superficial to the SCM muscle in the posterior triangle?

Answer 30

External jugular vein

Question 31

Posterior Triangle: What cervical nerves does the **Phrenic nerve** originate from?

Answer 31

C3, **_C4,_** C5

Question 32

What is **"scapular winging?"** What nerve is **damaged** (primarily) that results in scapular winging? What other nerve, when damaged, results in it? What muscle does this paralyze?

Answer 32

Question 33

Describe the **Shoulder** (aka "\_\_\_\_\_\_\_") **Joint**

Answer 33

**Shoulder (aka "Glenohumeral") Joint** * Synovial ball & socket joint * Relatively unstable due to: * lack of bony contact * absence of muscular support **INFERIORLY****​** * **​**Result: * **Great range** of mvmt * High incidence of **dislocation** * **​**socket is much smaller than head of humerus

Question 34

**SIX _INTRINSIC_ SHOULDER MUSCLES** * **Four** of which are *what kind* of muscles? * Describe the **innervation** of these 6 muscles

Answer 34

**SIX _INTRINSIC_ SHOULDER MUSCLES** * **Four** of which are ***ROTATOR CUFF*** muscles INNERVATION: * **4 peripheral** nerves (Of the _Brachial Plexus_) innervate **all 6** * **​**3 nerves branch from **POSTERIOR CORD** * **​**One is **terminal**, two are **pre**-terminal * One nerve branches from **SUPERIOR TRUNK** **​*****All four**carry fibers derived from**C5 & C6 ONLY!!!!!!***

Question 35

What does the shoulder (pectoral) girdle consist of? (2)

Answer 35

Clavicle Scapula

Question 36

What forms the **"cervical plexus?"**

Answer 36

**Ventral rami of C1-4**

Question 37

Where is the Shoulder Joint capsule the **WEAKEST?**

Answer 37

**INFERIORLY** almost all of the support in the shoulder joint comes from *above*

Question 38

What is the **QUADRANGULAR SPACE?** * What 2 structures go **through** this space? * What can **negatively** affect these structures? * What are the 4 borders that make up this space?

Answer 38

*_Two things go through the Quadrangular Space:_* 1. **Axillary Nerve** (innerv. delts & teres minor) 2. Posterior circumflex humeral **artery** ​*Both structures affected by _anteroinferior **shoulder dislocation**_* **Boundaries:** 1. Superior: the teres **minor** 2. Inferior: the teres **major** 3. Medially: the long head of the **triceps** brachii 4. Laterally: the surgical neck of the **humerus**

Question 39

Around how many ribs does the Axilla span?

Answer 39

~ 5 ribs

Question 40

Teres **MAJOR** is an ______ rotator and _______ of the humerus It is **NOT** *what kind of muscle?*

Answer 40

Teres major is an **internal** rotator and **adductor** of the humerus It is **NOT** a rotator cuff muscle (that's Teres MINOR)

Question 41

What does the "superficial chest" refer to?

Answer 41

‘Superficial chest’ refers to:the **anterior** group of **extrinsic** shoulder muscles: ## Footnote **• Pectoralis major and minor** **•Serratus anterior**

Question 42

What are the 3 boundaries of the Posterior Triangle?

Answer 42

1. SCM 2. Trapezius 3. Clavicle