2: Anatomy of clavicel, humerus and scapula

Question 1

Pectoral girdle is a bony ring, incomplete posteriorly, formed by the …………… and completed anteriorly by the …………..

Answer 1

Posterior: scapulae and clavicle
Anterior: manubrium of the sternum.

Question 2

The …(a)… surface of clavicle is smooth because it doesn’t have a lot of attachments, but the …(b)… surface is rough because it has a lot of attachments.

Answer 2

(a): anterior surface
(b): posterior surface

Question 3

When you fall on a straight arm, this bone will absorb the shocks from your arm (transmits shocks from UL to axial skeleton)

Answer 3

Clavicle

Question 4

What is the commonest area of fracture in clavicle?

Answer 4

connection between medial 2/3 & lateral 1/3

Question 5

Medial end of clavicle is pulled superiorly by …..?

Answer 5

SCM

Question 6

Lateral part of the clavicle & UL pulled inferiorly by ….?

Answer 6

Weight of arm and gravity (bcz trapezius is not strong enough to pull them superiorly)

Question 7

Lateral part of clavicle and UL pulled medially by …?

Answer 7

Pectoralis major ❓

Question 8

The scapula is overlying …..#….. ribs?

Answer 8

2nd to 7th
(So if Iam palpating the medial border and went more medial I will palpate T2 (2nd spine) Bcz it Extend from T2-T7)

Question 9

Scapula has 3 borders:
a. Lateral border is called …….
b. Medial border is called …….
c. Superior border

Answer 9

a. Axillary
b. Verterbral

Question 10

Answer 10

1. Acromial fracture
2. Coracoid fracture
3. Scapular body fracture
4. Glenoid fracture

Tafreegh: most fractures of scapula requires little treatment because it is covered on both sides by muscles, so if there is a fracture in your scapula you don’t even need to support it like other bone fractures

Question 11

A. What is the largest bone in the upper limb?
B. What does it articulate with?
C. What is the commonest sites of fracture in this bone?

Answer 11

A. Humerus
B. Articulates with the scapula at the glenohumeral joint + articulates with the radius and ulna at the elbow joints.
C. Surgical neck

Question 12

What artery + nerve are affected in case of humerus fracture at:
A. Surgical neck?
B. Midshaft?
C. Medial epicondyl?
D. Supracondylar?

Answer 12

Question 13

(Idk if it’s important): areas that you can palpate in shoulder region?

Answer 13

Question 14

The following picture shows X-ray in 1 year old child. What does it show? Fracture / normal?

Answer 14

Normal

Tafreegh: always check the age for the patient on X-rays, you may think it’s a fracture but maybe it’s a 1yrs old patient his bones are not ossified yet

Question 15

In case of fracture is in the middle of the humerus, what muscle will pull (abduct) that part of the bone superiorly and the rest weight of the hand will fall down?

Answer 15

Deltoid

Question 16

What is comminuted fracture?

Answer 16

A fracture with alot of small peices

Question 17

In case of avulsion fracture at greater tubercle of humerus, what muscles will pull this part of bone superiorly?

Answer 17

Rotator cuff (Supraspinatus & infraspinatus)

Question 18

What part of humerus is fractured?

Answer 18

Greater tubercle

Question 19

What part of humerus is fractured?

Answer 19

Surgical neck

Question 20

This part of humerus forms joint with ulna?

Answer 20

Trochlea

Question 21

This is a process that takes part w/ articulation with the radius?

Answer 21

Capitulum

Question 22

what divides the posterior aspect of the scapula into 2 parts, supraspinatus fossa & infraspunatus fossa.

Answer 22

Spine of scapula

Question 23

Which part of the clavicle is fractured in case of downward blow on shoulder?

Answer 23

Distal clavicle fracture

Question 24

What structure can be affected in case of posterior fracture or dislocation of sternoclavicular joint?

Answer 24

Trachea

Question 25

What structures are related to the clavicle?

Answer 25

Subclavian artery and vein, brachial plexus
Tafreegh: (So if the clavicle is broken you should look for hemorrhage and paralysis because of the vessels and nerves)

Question 26

What part of the clavicle is convex and which part is concave?

Answer 26

Medial end is convex (anteriorly)
and the lateral half is concave (anteriorly)

Question 27

Mcq: A 20-year-old female presented with right shoulder pain after falling from a bicycle. X-ray revealed fracture of the clavicle. Upon examination, the arm was pulled forwards and medially rotated. Which of the following muscles is responsible for this position?

Answer 27

Pectoralis major

Question 28

Mcq: When there is a posterior clavicle dislocation what will happen? (2019)

a. Abducted arm & lateral rotation
b. Adducted arm & medial rotation
c. Abducted arm & medial rotation
d. Adducted arm & lateral rotation

Answer 28

b. Adducted arm & medial rotation

Question 29

(Greys Q): While walking to his classroom building, a first year medical student slipped on the wet pavement and fell against the curb, injuring his right arm.

Radiographic images showed a midshaft fracture of the humerus. Which pair of structures was most likely injured at the fracture site?

A. Median nerve & brachial artery
B. Axillary nerve & posterior circumflex humeral artery
C. Radial nerve & deep brachial artery
D. Suprascapular nerve & artery
E. Long thoracic nerve & lateral thoracic artery

Answer 29

C. Radial nerve & deep brachial artery

Question 30

(Greys Q): An 18-year-old man is brought to the emergency department after an injury while playing rugby. Imaging reveals a transverse fracture of the humerus about 1 inch proximal to the epicondyles. Which nerve is most frequently injured by the jagged edges of the broken bone at this location?

A. Axillary
B. Median
C. Musculocutaneous
D. Radial
E. Ulnar

Answer 30

B. Median

Question 31

(Greys Q): A 31-year-old male hockey player fell on his elbow and is admitted to the emergency department. Radiographic examination reveals a fracture of the surgical neck of the humerus, producing an elevation and adduction of the distal fragment.

Which of the following muscles would most likely cause the adduction of the distal fragment?
A. Brachialis
B. Teres minor
C. Pectoralis major
D. Supraspinatus
E. Pectoralis minor

Answer 31

C. Pectoralis major

Question 32

(Greys Q): A male skier had a painful fall against a rocky ledge. Radiographic findings revealed a hairline fracture of the surgical neck of the humerus. The third-year medical student assigned to this patient was asked to determine whether there was injury to the nerve associated with the area of injury.

Which of the following tests would be best for checking the status of the nerve?

A. Have the patient abduct the limb while holding a 10 lb weight
B. Have the patient shrug the shoulders
C. Test for presence of skin sensation over the lateral side of the shoulder
D. Test for normal sensation over the medial skin of the axilla
E. Have the patient push against an immovable object like a wall and assess the position of the scapula

Answer 32

C. The axillary nerve passes dorsally around the surgical neck of the humerus (accompanied by the posterior circumflex humeral artery) and can be injured when the humerus is fractured at that location. The axillary nerve provides sensation to the skin over the upper, lateral aspect of the shoulder. There- fore, although the patient might not be able to abduct the arm because of the injury, a simple test of skin sensation can indicate whether there is associated nerve injury of the axillary nerve.

Question 33

(Greys Q): A 24-year-old female basketball player is admitted to the emergency department after an injury to her shoulder. Radiographic examination reveals a shoulder dislocation.

What is the most commonly injured nerve in shoulder dislocations?
A. Axillary
B. Radial
C. Median
D. Ulnar
E. Musculocutaneous

Answer 33

A. Axillary

(Explanation: A. The axillary nerve is a direct branch of the posterior cord and wraps around the surgical neck of the humerus to innervate the teres minor and the deltoid muscles. With this anatomic arrangement, the axillary nerve is tightly “tethered” to the proximal humerus. When the head of the humerus is dislocated, it often puts traction on the axillary nerve)

Question 34

(Greys Q): A 65-year-old man is admitted to the emergency department after falling on his outstretched hand. The patient complains of severe right shoulder pain. Upon physical examination, the patient holds his arm externally rotated and slightly abducted. There is also flattening and sensory loss over the right deltoid muscle.

Which of the following is the most likely diagnosis?
A. Anterior dislocation of the humerus
B. Acromioclavicular joint subluxation
C. Clavicular fracture
D. Spiral fracture of the humeral midshaft
E. Rotator cuff tear

Answer 34

A. Anterior dislocation of the humerus (axillary nerve affected)

Question 35

(Greys Q): An emergency department physician examines a patient who fell from a motorcycle and injured his shoulder. The clinician notices a loss of the normal contour of the shoulder and an abnormal appearing depression below the acromion.

Which of the following injuries did the patient most likely sustain?
A. Avulsion of the coronoid process
B. Dislocated shoulder joint
C. Fracture of the midshaft of the humerus
D. Fracture of the surgical neck of the humerus
E. Laceration of the axillary branch of the posterior cord

Answer 35

B. Dislocated shoulder joint

(Explanation: B. The glenohumeral joint is an extremely mobile joint with a wide range of motion. Anterior dislocation of the humerus is most common and usually associated with an isolated traumatic incident. When the head of the humerus is displaced anteriorly and inferiorly, flattening of the deltoid prominence occurs, leading to loss of the normal contour of the humerus. There is protrusion of the acromion, and the slope of the shoulder lateral to the acromion is depressed and has a “dented” appearance. )

Question 36

(Greys Q): A 67-year-old woman with osteoporosis injured her left shoulder/arm in a fall. Examination reveals bruising and dimpling of the upper part of the arm with exquisite tenderness over the affected area. The shoulder radiograph is shown in Figure 6-13. Which nerve is most likely to be injured?

A. Radial
B. Axillary
C. Ulnar
D. Median

Answer 36

B. Axillary