Lecture 3.3

Question 1

What causes bicipital tendonitis?

Answer 1

Long head of biceps can cut through the bicipital groove causing pain This results in bicipital tendonitis.

Question 2

Where does each head of the biceps originate?

Answer 2

Short head of biceps originates from the coracoid process of the scapula.
Long head of the biceps originates at the supraglenoid tubercle of the scapula it then passes through the intertubercular groove.

Question 3

What causes popeye syndrome?

Answer 3

Proximal or distal insertion can get avulsed this causes popeye syndrome. In this case tendon needs to be surgically fixed.

Question 4

What are the muscles of the posterior compartment of the arm?

Answer 4

Triceps and anconeus.

Question 5

What nerve supplies posterior comparment of the arm?

Answer 5

Radial nerve

Question 6

Where does the long head of the triceps originate?

Answer 6

Long head: infraglenoid tubercle of scapula.

Question 7

Where do the lateral and medial heads of the triceps originate?

Answer 7

Lateral head: above the radial sulcus.
Medial head: below the radial sulcus

Both of these points are on the shaft of the humerus.

Question 8

Where do the triceps insert?

Answer 8

all 3 bellies of the heads of the triceps converge and insert onto the olecranon process of the ulna.

Question 9

What is the function of the triceps?

Answer 9

The triceps can work on extinding at shoulder joint and on the elbow joint.
Long head can also assist in adduction.

Question 10

What is the origin and insertion of the anconeus?

Answer 10

Anconeus is small muscle that starts at supracondylar ridge and inserts onto the ulna.

Question 11

What is the function of the anconeus?

Answer 11

It assists the triceps in extension.

Question 12

Which nerve roots form the radial nerve?

Answer 12

C5 - T1

Question 13

In which fracture is the radial nerve endangered?

Answer 13

Midshaft fracture.

Question 14

Where do the suprascapular nerve and artery travel relative to the suprascapular foramen and the transverse ligament of the scapula?

Answer 14

Suprascapular nerve goes through suprascapular foramen.

Suprascapular artery travels superior to the transverse ligament of scapula.

Question 15

What are the boundaries of the quadrangular space?

Answer 15

Teres minor
Teres major
Long head of the triceps
Humerus

Question 16

What structures travel through the quadrangular space

Answer 16

Axillary nerve

Posterior humeral circumflex artery.

Question 17

What are the boundaries of the triangular space?

Answer 17

Teres major
Long head of the triceps
Supscapularis superiorly and teres minor superiorly

Question 18

Where do the axillary nerve and the posterior humeral circumflex artery go after passing through the quadrangular space? What is the problem with this passage?

Answer 18

Posterior humeral circumflex artery and the axillary nerve go around the surgical neck of the humerus and are susceptible to damage from breaking of the surgical neck.

Question 19

What structures pass through the triangular space?

Answer 19

Circumflex scapular artery (goes to posterior side and supplies posterior side of the scapula.)

Question 20

What are the boundaries of the triangular interval?

Answer 20

Humerus

Long head of the triceps

Question 21

What is the function of the circumflex scapular artery?

Answer 21

Major blood supply for the posterior muscles of the scapula.

Question 22

What structures pass through the triangular interval?

Answer 22

Radial nerve

Profunda brachii (deep brachial artery)

Question 23

What structure of the humerus does the ulna hold onto?

Answer 23

Trochlea takes semilunar notch of the ulna.

Question 24

Where does the semilunar notch sit in flexion?

Answer 24

Coranoid fossa is the hole in which the ulna’s coranoid fossa sits.

Question 25

Where does the radial notch sit while in flexion?

Answer 25

Radial fossa.

Question 26

Where does the ulna sit on the humerus when in extension?

Answer 26

The olecranon fossa.

Question 27

Which of the radius and the ulna is wide proximally and narrow distally?

Answer 27

Ulna. Head is distal

Question 28

What is the name of the projection of the ulna and the radius that incorporates the carpal bones?

Answer 28

The styloid processes.

Question 29

What is the notch that holds the radius to the ulna proximally?

Answer 29

Radial notch of ulna

Question 30

What is the notch that holds the ulna to the radius distally?

Answer 30

The ulnar notch of radius.

Question 31

What type of joint does the interosseus membrane form and what is the function of this?

Answer 31

Interosseus membrane forms a syndesmosis joint between radius and ulnar this transfers force from one bone to the other bone.

Question 32

What kind of fracture happens to the radius and ulna in a FOOSH?

Answer 32

Colles fracture of radius causes hand to move posteriorly and flex slightly. This fracture often transfers to the ulna.

Question 33

What kind of injury can happen to the ulnar from falling on a flexed elbow?

Answer 33

falling on flexed elbow can cause olecranon process to break away and this endangers the structures of the cubital fossa. Most importantly the median nerve and the brachial artery. This in turn can cause volkmann’s ischaemia and contracture.

Question 34

What is the sequence of structures affected by compartment syndrome?

Answer 34

Veins/lymphatics -> Superficial nerves -> Arteries -> deep nerves

Question 35

What are the boundaries of the cubital fossa.

Answer 35

Roof: bicipital aponeurosis
Pronator teres on the medial side.
Brachioradialis on the lateral side.
Floor: Brachialis

Question 36

What are the contents of the cubtal fossa?

Answer 36

Median cubital vein

Lateral cutaneous nerve of the forearm and medial cutaneous nerve of the forearm.

Ulnar and radial arteries.

Median and radial nerves.

Question 37

What are the main principles regarding the difference between anterior and posterior compartments?

Answer 37

Skin overlying flexor muscles is more sensitive than over extensors.

Flexor muscles are stronger than extensor muscles

Question 38

What nerves supply the forearm?

Answer 38

Forearm supplied by median, ulnar, and radial nerve.

Question 39

How many flexor muscles are there in the anterior compartment of the forearm? How many in each layer?

Answer 39

8;

4 superficial

1 intermediate

3 deep

Question 40

What are the origin and insertion of the pronator teres?

Answer 40

Pronator teres starts from ulnar and goes to radius and does not cross the wrist.

Question 41

Where doe the superficial forearm muscles originate?

Answer 41

The common flexor origin at the medial epicondyle.

Question 42

Where does Flexor carpi radialis insert?

Answer 42

Bases of second and third metacarpal bones

Question 43

Where is palmaris longus located? Where does it insert? What is the clinical significance of it being absent in 15% of the population?

Answer 43

Palmaris Longus inserts onto the palmar aponeurosis. Palmaris longus sits right on top of the median nerve and protects it in its absense the median nerve is exposed and prone to injury.

Question 44

What nerve innervates flexor carpi ulnaris and where does this muscle insert?

Answer 44

Flexor carpi ulnaris is innvervated by the ulnar nerve and inserts onto the pisiform and the 5th metacarpal.

Question 45

What is the muscle of the intermediate layer?

Answer 45

Flexor digitorum superficialis.

Question 46

Where does the muscle of the intermediate layer originate and where does it insert?

Answer 46

Origin: Common Flexor Origin + shaft of the radius + shaft of the ulna.

this muscle goes deep to the flexor retinaculum.

Insertion: Base of the middle phalanges after splitting. Each split end inserts onto the medial and lateral sides of the phalanges.

Question 47

What are the deep layer muscles of the flexor compartment?

Answer 47

Flexor Pollicis Longus

Flexor Digitorum Profundus

Pronator Quadratus

Question 48

What is the origin of the deep muscles of the flexor compartment of the forearm?

Answer 48

Radius + Ulna +/- IO membrane

Question 49

Where does flexor pollicis longus insert?

Answer 49

Flexor pollicis longus inserts onto the distal phallanx of the thumb.

Question 50

What structures do the tendons of flexor digitorum profundus pass through when inserting at the distal phallanges?

Answer 50

Flexor digitorum profundus goes through the space formed by split tendons of the flexor digitorum superficialis and inserts onto the distal phallanges.

Question 51

What is the function of pronator quadratus?

Answer 51

Pronator Quadratus goes from ulna to radius and assists pronator teres in pronation.

Question 52

Which muscles are responsible for supination of the forearm?

Answer 52

Supinator is a muscle in the posterior compartment that allows supination along with the biceps

Question 53

Which bone moves during pronation and supination?

Answer 53

Pronation and supination is movement of the radius relative to ulna. ( i remember this by the hooking of the ulna at the elbow preventing the ulna from twisting.)

Question 54

Where do superficial muscles of the extonsor compartment originate? What is the exception to this rule?

Answer 54

Superficial extensor compartment start at common extensor origin on the lateral epicondyles. Brachioradialis is an exception and start from the lateral supracondylar ridge.

Question 55

What is the function and innervation of brachioradialis?

Answer 55

Brachioradialis is innervated by radial nerve but functionally it works with anterior compartment and is found at the border between compartments. It assists with flexion of the elbow.

Question 56

Where do extensor carpi radialis longus and brevis insert (respectively)?

Answer 56

2nd and 3rd metacarpals

Question 57

Where does extensor digiti minimi insert and what is the advantage of this muscle?

Answer 57

At the extensor expansion at the base of the proximal phallanx.

The advantage of this muscle is that the small digit can be extended independantly of the other digits.

Question 58

Where does extensor carpi ulnaris insert?

Answer 58

The 5th metacarpal

Question 59

What happens when both flexor carpi ulnaris and extensor carpi ulnaris work together? What about on the radial side?

Answer 59

If flexor and extensor carpi ulnaris work together this allows ulnar deviation. Opposite is true for radialis muscles.

Question 60

What nerve crosses the 2 heads of the pronator teres?

Answer 60

The median nerve

Question 61

What artery lies laterally to the flexor carpi radialis?

Answer 61

The radial artery.

Question 62

Where does the extensor digitorum communis insert?

Answer 62

Superficial to the extensor carpi radialis longus and brevis is the extensor digitorum communis which inserts onto the medial 4 digits. Tendons of this muscle form extensor expansion hoods.

Question 63

Is the ulnar artery palpable?

Answer 63

Ulnar artery’s pulse can be felt but it is hard to because it is pretty deep.