1: anatomy of deltoid, pectoral and scapular regions

Question 1

What’s the blood supply to glenohumeral joint?

Answer 1

Anterior and posterior circumflex humeral arteries

Question 2

Fascia at pectoral region attaches to what bones?

Answer 2

Clavicle & sternum

Question 3

What ligament is responsible of holding the skin when adducting the arm

Answer 3

Suspensory ligament (which is thickening of pectoral fascia)

Question 4

The muscle works from insertion to origin. Which is proximal and which is distal?

Answer 4

Origin (proximal)
Insertion (distal)

Question 5

Pectoralis major (origin, insertion, action, innervation)

Answer 5

• Origin (proximal attachment): clavicle, superior six costal cartilages.
• Insertion (distal attachment): Intertubercular groove of humerus.
• Function : adduct and medially rotates humerus.
• Innervation : lateral & medial pectoral nerves.

Question 6

Pectoralis minor (origin, insertion, action, innervation)

Answer 6

• Origin : 3rd-5th ribs
• Insertion : coracoid process of scapula
• Function : stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall
• Innervation : medial pectoral nerve

Question 7

This muscle helps you raise the scapula slightly when trying to reach something upward

Answer 7

Pectoralis minor

Question 8

Subclavius (origin, insertion, action, innervation)

Answer 8

• Origin : 1st rib
• Insertion : inferior surface of the clavicle
• Action : anchors and depresses clavicle
• Innervation : nerve to subclavius

Question 9

Serratus anterior (origin, insertion, action, innervation)

Answer 9

• Origin: lateral parts of 1st-8th ribs.
• Insertion: anterior surface of the medial border of scapula.
• Action: protracts scapula and holds it against thoracic wall, rotates scapula.
• Innervation: long thoracic nerve.

Question 10

Trapezius (origin, insertion, action, innervation)

Answer 10

• Origin: external occipital protuberance, superior nuchal line of occipital bone, ligamentum nuchae, spinous processes C7 & T1-T12.
• Insertion: posterior border of the lateral third of clavicle, acromion and scapular spine.
• Action: rotate the scapula for full abduction, elevate the shoulder, retract the shoulder and draw scapula downward.
• Innervation: accessory nerve.

Question 11

Lattisimus dorsi (origin, insertion, action, innervation)

Answer 11

• Origin: aponeurosis of thoracolumber fascia, spinous processes of lower 6 thoracic vertebrae, iliac crest
• Insertion: intertubercular groove of humerus
• Action: extend, adduct, and medially rotates the humerus
• Innervation: thoracodorsal nerve

Question 12

Rhomboids (origin, insertion, action, innervation)

Answer 12

• Origin : spinous processes of C7 –T5
• Insertion : medial border of scapula
• Function : retract scapula and rotate it to depress glenoid cavity, fix scapula to thoracic wall
• Innervation : dorsal scapular nerve

Question 13

Levator scapulae (origin, insertion, action, innervation)

Answer 13

• Origin : posterior tubercles of transverse processes of C1-C4 vertebrae
• Insertion : medial border of scapula superior to root of spine.
• Action : elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula.
• Innervation : dorsal scapular and cervical nerves.

Question 14

Deltoid (origin, insertion, action, innervation)

Answer 14

• Origin: lateral third of clavicle, superior surface of the acromion, and spine of the scapula
• Insertion: deltoid tuberosity
• Action: abduct the arm with supraspinatus, medial and lateral rotation + (slight flexion & extension at walking)
• Innervation: axillary nerve

Question 15

Subscapularis

Answer 15

• Origin: subscapular fossa
• Insertion: lesser tubercle
• Action: medially rotate and adduct arm
• Innervation: upper and lower subscapular

Question 16

Supraspinatus

Answer 16

• Origin: supraspinatus fossa
• Insertion: greater tubercle
• Action: initiates abduction, lateral rotator of humerus
• Innervation: suprascapular nerve

Question 17

Infraspinatus & teres minor

Answer 17

• Origin: Infraspinatus fossa (infraspinatus), posterolateral surface of scapula scapula (teres minor)
• Insertion: greater tubercle
• Action: laterally rotate arm
• Innervation: axillary (teres minor), suprascapular (infraspinatus)

Question 18

Teres Major

Answer 18

• Origin: scapula
• Insertion: intertubercular groove of humerus
• Action: adduct and medially rotates
• Innervation: lower subscapular

Question 19

What muscle holds scapula in place?

Answer 19

Pectoralis minor

Question 20

Boxer’s muscle

Answer 20

Serratus anterior

Question 21

A patient presented with winging of scapula, what’s the problem?

Answer 21

Question 22

Answer 22

A. Pectoralis major

Question 23

What’s this muscle?

Answer 23

Subclavius

Question 24

When you’re hanging, this muscle will bring your body towards your arms so it’s the muscle that pulls the body/

Answer 24

Lattisimus Dorsi

Question 25

Main medial rotator ?

Answer 25

Subscapularis

Question 26

Initiates abduction?

Answer 26

Supraspinatus

Question 27

The triangle of auscultation is a good spot to ascultate the lungs. Where is this triangle located?

Answer 27

Between border of scapula and trapezius

Question 28

muscle that elevate the medial fragment of fractured clavicle?

Answer 28

SCM (sternocleidomastoid)

Question 29

Which muscle is attached proximally to the coracoid process?

a. Pectoralis major
b. Pectoralis minor
c. Subclavius
d. Coracobrachialis

Answer 29

D. Coracobrachialis

Question 30

Which muscle is responsible for shrugging off against resistance?

a. Trapezius
b. Subclavius
c. Biceps
d. Rhomboids

Answer 30

A. Trapezius ( shrugging off against resistance = elevate the shoulder)

Question 31

Which muscle is used for pushing the trunk up while climbing a tree?

Answer 31

Latissimus Dorsi

(from google , pushing the trunk up = need powerful adductor muscles [ pectorals major + latissimus dosri + teres major )

Question 32

First 15 degrees of abduction is by this muscle

Answer 32

Answer: Supraspinatus

(Note: Beyond that deltoid abducts)

Question 33

What muscle swings the arm back and forth while walking?

Answer 33

Deltoid

Question 34

What is a consequence of rotator cuff muscle injury?
a. Painful arc
b. Bursitis
c. Tendinitis
d. Sprain

Answer 34

A. Painful arc

Question 35

Which nerve damage causes winging of scapula?

Answer 35

Long thoracic nerve

Question 36

Which rotator cuff muscle is easily impinged?

Answer 36

Supraspinatus

Question 37

What action is lost if Subscapular nerve is affected?

Answer 37

Medial shoulder rotation

Question 38

Injury to spinal accessory nerve lead to paralysis of which muscle?

Answer 38

Trapezius

Question 39

Which two muscles are the chief lateral rotators?

Answer 39

Infraspinatus + Teres minor

Question 40

Injury to which nerve results in the inability to initiate abduction?

Answer 40

Suprascapular nerve

Question 41

Injury to which nerve results in the inability to retract the scapula?

Answer 41

Dorsal scapular nerve

Question 42

Boxer said: “Ow, I can’t punch!”. Which nerve is injured?

Answer 42

Long thoracic nerve

Question 43

In fracture of the middle part of the clavicle, the proximal side is elevated while the lateral part is stationary. What keeps the lateral side in such position?

Answer 43

Coracoclavicular ligament

Question 44

What structure depresses the clavicle and is associated with the subclavian groove of the clavicle?

Answer 44

Subclavius

Question 45

Scapular winging occurs in:
a. Roots injury
b. Superior trunk injury
c. Inferior trunk injury
d. Divisions injury
e. Medial cord injury

Answer 45

a. Roots injury

Question 46

(Greys Qs): A
27-year-old man was admitted to the emergency department after an automobile collision in which he suffered a fracture of the lateral border of the scapula. Six weeks after the accident, physical examination reveals weakness in medial rotation and adduction of the humerus. Which nerve was most likely injured?

A. Lower subscapular
B. axillary
C. radial
D. spinal accessory
E.ulnar

Answer 46

A. Lower subscapular
(Teres major affected)

Question 47

(Greys Qs): A
55-year-old man is examined in a neighborhood clinic after receiving blunt trauma to his right axilla in a fall. He has difficulty elevating the right arm above the level of his shoulder. Physical examination shows that the inferior angle of his right scapula protrudes more than the lower part of the left scapula. The right scapula protrudes far more when the patient pushes against the examiner’s hand with resistance. Which of the following neural structures has most likely been injured?

A. The posterior cord of the brachial plexus
B. The long thoracic nerve
C. The upper trunk of the brachial plexus
D. The site of origin of the middle and lower
subscapular nerves
E. Spinal nerve ventral rami C7, C8, and T1

Answer 47

B. The long thoracic nerve

Question 48

(Greys Qs): A 19-year-old man is brought to the emergency
department after dislocating his shoulder while playing
soccer. Following reduction of the dislocation, he has pain over the dorsal region of the shoulder and cannot abduct the arm normally. An MRI of the shoulder shows a torn muscle. Which of the following muscles is most likely to have been damaged by this injury?

A. Coracobrachialis
B. Long head of the triceps brachii
C. Pectoralis minor
D. Supraspinatus
E. Teres major

Answer 48

D. Supraspinatus

Question 49

(Greys Q): A 35-year-old male wrestler is admitted to the
emergency department with excruciating pain in his right shoulder and proximal arm. During physical examination, the patient clutches the arm at the elbow with his contralateral hand and is unable to move the injured limb. Radiographic studies show that the patient has a dislocation of the humerus at the glenohumeral joint. Which of the following conditions is the most likely?

A. Head of humerus is displaced anteriorly
B. Head of humerus is displaced Posteriorly
C. Head of humerus is displaced inferiorly
D. Head of humerus is displaced medially

Answer 49

C. The head of humerus is displaced inferiorly because in that location it is not supported by the rotator cuff muscles tendons or the coracoacromial arch.

Question 50

(Greys Q): During a fight in a tavern, a 45-year-old male construction worker received a shallow stab wound from a broken beer bottle at a point near the middle of the left posterior triangle of his neck. Upon physical examination, it is observed that the left shoulder is drooping lower than the right shoulder, and the superior angle of the scapula juts out slightly. Strength in turning the head to the right or left appears to be symmetric.

Which of the following nerves is most likely injured?
A. Suprascapular nerve in the supraspinous fossa
B. The terminal segment of the dorsal scapular nerve
C. The upper trunk of the brachial plexus
D. The spinal accessory nerve in the posterior cervical triangle
E. The thoracodorsal nerve in the axilla

Answer 50

D. The spinal accessory nerve in the posterior cervical triangle

Question 51

(Greys Q): A
45-year-old woman is admitted to the hospital with neck pain. A computed tomography (CT) scan reveals a tumor on the left side of her oral cavity. The tumor and related tissues are removed and a radical neck surgical procedure is performed. Two months
postoperatively the patient’s left shoulder droops quite noticeably. Physical examination reveals distinct weakness in turning her head to the right and impairment of abduction of her left upper limb to the level of the shoulder.

Which of the following structures was most likely injured during the radical neck surgery?
A. Suprascapular nerve
B. Long thoracic nerve
C. Spinal accessory nerve
D. The junction of spinal nerves C5 and C6 of the brachial plexus
E. Radial nerve

Answer 51

C. Spinal accessory nerve

Question 52

Shoulder droops what nerve and muscle affected?

Answer 52

Spinal accessory nerve
Trapezius muscle

Question 53

(Greys Q): A 43-year-old man visits the outpatient clinic with a painful shoulder. Physical examination reveals a painful arc syndrome due to supraspinatus tendinopathy. Which of the following conditions are expected to be present during physical examination as the patient abducts his arm?

A. Painful abduction 0 to 15
B. Painful abduction 0 to 140
C. Painful abduction 70 to 140
D. Painful abduction 15 to 140
E. Painful abduction 40 to 140

Answer 53

A. Painful abduction 0 to 15 degrees

Question 54

(Greys Q): A 36 year old woman is admitted to the emergency department after an athletic injury that has caused weakness in both lateral rotation and the initial 15 to 20° of abduction of the arm which nerve was most probably injured?

Answer 54

Suprascapular nerve

Question 55

What’s the nerve supply for glenohumeral joint?

Answer 55

Nerve supply by suprascapular, axillary, and lateral pectoral pectoral nerves.

Question 56

What are axioappendicular muscles (anterior)?

Answer 56

Question 57

What are axioappendicular muscles (posterior)?

Answer 57

Question 58

Clinical relevance of fascia (good + bad)?

Answer 58

Question 59

(Greys Q): After an orthopedic surgeon examined the MRI of the shoulder of a 42-year-old woman he informed her that the supraspinatus tendon was injured and needed to be repaired surgically. Which of the following is true of the supraspinatus muscle?

A. It inserts onto the lesser tubercle of the humerus.
B. It initiates adduction of the shoulder.
C. It is innervated chiefly by the C5 spinal nerve.
D. It is supplied by the upper subscapular nerve.
E. It originates from the lateral border of the scapula.

Answer 59

C. The supraspinatus muscle inserts on the greater tubercle of the humerus and is said to initiate abduction of the arm at the shoulder. It is supplied principally by spinal nerve C5. The subscapularis muscle is the only muscle that inserts on the lesser tubercle. The subscapularis muscle is innervated by the upper and lower subscapular nerves. The teres minor muscle takes origin from the lateral border of the scapula; the teres major muscle takes origin from. the region of the inferior angle and the lateral border of the scapula.

Question 60

(Greys Q): A 21-year-old woman who is an athlete dislocated her glenohumeral joint while playing soccer and the shoulder was reduced in the emergency department. However, after 1 week the physician noted that the woman had lost strength when she attempted internal rotation of her arm at the shoulder.

This finding was most likely caused by a tear in which of the following muscles?
A. Infraspinatus
B. Pectoralis minor
C. Subscapularis
D. Supraspinatus
E. Teres minor

Answer 60

C. Subscapularis

(Explanation: Anterior dislocation of the humerus may damage the nerves located in the axilla or cause tears in the rotator cuff muscles. Internal rotation is the primary function of subscapularis muscle; with this being the only action impaired it is the most likely damaged muscle, probably as a result of injury to the upper and/or lower subscapular nerves that innervate this muscle.)

Question 61

Shoulder joint movements

Answer 61