Upper limb anatomy

Question 1

What is the clavicopectoral triangle

Answer 1

The last passageway is the clavipectoral triangle, which is an opening in the anterior wall of the axilla. It is bounded by the pectoralis major, deltoid, and clavicle. The cephalic vein enters the axilla via this triangle, while the medial and lateral pectoral nerves leave.

Question 2

What are the boundaries of the antecubital fossa

Answer 2

Anticubital fossa
Borders
The cubital fossa is triangular in shape and consists of three borders, a roof, and a floor:
* Lateral border – medial border of the brachioradialis muscle.
* Medial border – lateral border of the pronator teres muscle.
* Superior border – horizontal line drawn between the epicondyles of the humerus.
* Roof – bicipital aponeurosis, fascia, subcutaneous fat and skin.
* Floor – brachialis (proximally) and supinator (distally).

Question 3

What are the boundaries of the cubital tunnel

Answer 3

• Medial wall – medial epicondyle of the humerus.
• Lateral wall – olecranon of the ulna.
• Floor – elbow joint capsule and medial collateral ligament of the elbow.
• Roof – ligament spanning between the medial epicondyle and olecranon

The ligament forming the roof of the cubital tunnel is also known as the cubital tunnel retinaculum or the arcuate ligament of Osbourne. It is a band of fascia which runs between the ulnar and humeral heads of the flexor carpi ulnaris.

Question 4

How many tendons does the carpal tunnel have

Answer 4

The carpal tunnel has 9 tendons
* The tendon of flexor pollicis longus
* Four tendons of flexor digitorum profundus
* Four tendons of flexor digitorum superficialis

Question 5

Describe the anatomy of the extensor compartment

Answer 5

Compartment 1 tendon inflammation results in deQ Tenosynovitis
Compartment 2 contains Lister’s tubercle – a bony prominence of the distal aspect of the radius.
Compartment 3 forms the medial border of the anatomical snuffbox

Question 6

What are the boundaries of the anatomical snuff box

Answer 6

As the snuffbox is triangularly shaped, it has three borders, a floor, and a roof:
* Ulnar (medial) border: Tendon of the extensor pollicis longus.
* Radial (lateral) border: Tendons of the extensor pollicis brevis and abductor pollicis longus.
* Proximal border: Styloid process of the radius.
* Floor: Carpal bones; scaphoid and trapezium.
* Roof: Skin.

The main contents of the anatomical snuffbox are the radial artery, a branch of the radial nerve, and the cephalic vein:
* Radial artery – crosses the floor of the anatomical snuffbox, then turns medially and travels between the heads of the adductor pollicis muscle.
o The radial pulse can be palpated in some individuals by placing two fingers on the proximal portion of the anatomical snuffbox.
* Superficial branch of the radial nerve
* Cephalic vein

Question 7

2 heads rule

Answer 7

Median nerve passes through the 2 heads of the pronator teres as well as flex dig sup
ulnar artery apssess between 2 heads of flexor carpi ulnaris

Question 8

How is the axillary artery divided

Answer 8

The main branches of the axillary artery include:
First Part
Superior thoracic artery

Second Part
Thoracoacromial artery
Lateral thoracic artery

Third Part
Subscapular artery
Anterior and posterior circumflex arteries

Question 9

When does the axillary artery become the brachial artery

Answer 9

At the lower border of the teres major muscle. Immediately distal to the teres major, the brachial artery gives rise to the profunda brachii (deep artery),

Question 10

Where are the parts of the brachial plexus found

Answer 10

Roots: Exit the intervertebral foramen between the anterior and middle scalene muscle
Trunks - Base of the post triangle of the neck. They lie over the 1st Rib behind the 3rd part of the subclavian artery
Divisions: Post to the middle third of the clavicle
Cords: related to the second part of Ax nerve
Terminal branches: Related to 3rd part of Ax nerve

Question 11

Median cutaneous nerve roots

Answer 11

C8, T1

Question 12

Thoracodorsal nerve roots

Answer 12

Posterior cord C6,C8

Question 13

What is the ulnar paradox

Answer 13

The closer to the paw, the worse the claw. Injury at the wrist will spare the ulnar branch to the flex dig profundus and cause worsened clawing of the hand

Question 14

Where dose the flexor retinaculum of the wrist attach

Answer 14

Proximally to the pisi and the tubercle of the scaphoid
Distally hook of hamate and trapezium

Question 15

What prevents bow stringing of the flexor retinaculum tendons

Answer 15

Intricate fascial pulley system and the flexor retinaculum

Question 16

What are the muscles that attach to the greater tuberosity

Answer 16

Supraspinatus, infraspinatus and teres minor GT
subscapularis LT

Question 17

Where does the long head of the biceps brachii originate

Answer 17

Supraglenoid tubercle

Question 18

Where do the pec major, lat dorsi and teres major attach

Answer 18

Question 19

Surgical vs anatomical neck of humerus

Answer 19

Question 20

What muscles attach to the coracoid process

Answer 20

Short head of biceps brachii, coracobrachialis and the pec minor

Question 21

Where does the biceps tendon insert

Answer 21

Radial tuberosity, fans into the bicipital aponeurosis in the antecubital fossa

Question 22

Under what ligament does the supraspinatus muscle commonly get impinged

Answer 22

Coracoacromial ligament

Question 23

Triangular space vs triangular interval

Answer 23

Triangular interval - Radial nerve and profunda brachii
Triangular space - Circumflex scapular vessels

Question 24

WHat nerve supplies the rhomboid muscles and where does it originate

Answer 24

Dorsal scapular nerve C5 brachial plexus

Question 25

Action of the serratus anterior on the scapula

Answer 25

lateral rotation and protraction Long thoracic nerve C5, C5 and C7

Question 26

What is the surface anatomy of the coracoid process

Answer 26

Palpable guide to the deltopectoral groove. Glenohumeral tube is one finger breadth lateral to the coracoid process

Question 27

The blood supply to the rotor cuff

Answer 27

Ant and post circumflex arteries, thoracoacromial as well as subscapular artery

Question 28

What is the painful arc

Answer 28

Painful abduction between 60-120 degrees and is caused by supraspinatus tendonitis

Question 29

Name the branches of the lateral cord of the brachial plexus

Answer 29

Lateral pec and lateral root of median nerve and musculocutaneous nerve

Question 30

Branches of the medial cord

Answer 30

Median pec nerve, medial cutaneous nerve of the arm and forearm, median root of the median nerve and ulnar nerve

Question 31

Branches of the posterior cord

Answer 31

Axillary and radial nerve Upper subscapular nerve Lower scapular nerve THoracodorsal nerve

Question 32

Name the boundaries of the axilla

Answer 32

Apex – also known as the axillary inlet, it is formed by lateral border of the first rib, superior border of scapula, and the posterior border of the clavicle. Lateral wall – formed by intertubercular groove of the humerus. Medial wall – consists of the serratus anterior and the thoracic wall (ribs and intercostal muscles). Anterior wall – contains the pectoralis major and the underlying pectoralis minor and the subclavius muscles. Posterior wall – formed by the subscapularis, teres major and latissimus dorsi.

Question 33

What are the levels of the axillary lymph nodes

Answer 33

Level 1: Below pec minor Level 2: Behind pec minor Level 3: Above the pec minor

Question 34

What are the structures that can be affected in an axillary node clearance

Answer 34

Axillary vein, Long thoracic Thoracodorsal Intercostobranchial - innervated the skin of the upper arm medial and posterior

Question 35

What is the clavicopectoral fascia and what goes through it

Answer 35

It extends from the axillary fascia and encloses the pec min and maj as well as the subclavius. Lat pec nerve, thoracodorsal trunk, cephalic vein and lymphatics pass through it

Question 36

What are the boundaries of the cubital tunnel

Answer 36

Medial wall – medial epicondyle of the humerus. Lateral wall – olecranon of the ulna. Floor – elbow joint capsule and medial collateral ligament of the elbow. Roof – ligament spanning between the medial epicondyle and olecranonz

Question 37

What to do if there is a suspected scaphoid fracture

Answer 37

Immobilise for 6 weeks. if it is a distal pole fracture, for proximal pole, consider internal fixation.

Question 38

What is the guyon's canal

Answer 38

It is a space between the pisiform bone and the hamate

Question 39

What are the points of attachment of the flexor retinaculum

Answer 39

Hook of hamate and pisiform bone on the ulnar side Scaphoid and trapezium on the radial side

Question 40

What structures pass OVER the carpal tunnel

Answer 40

Palmaris longus tendon, Cutaneous branch of the median nerve and superficial branch of the radial artery

Question 41

WHat is the significance of the kaplans cardinal line

Answer 41

Superficial palmar arch lies distal to this lone and can be injured by incisions that cross this line.

Question 42

Describe the palmar fascia

Answer 42

Superficial layer with long fibers Intermediate with transverse fibers Deep layer with vertical fibers

Question 43

What is a trigger finger?

Answer 43

Unknown aetiology and disruption of the pulley system causes the flexor tendons to get stuck

Question 44

What is a mallet finger

Answer 44

Disruption of the distal extensor tendons of the finger, there is pain and swelling in the fingers as well as an inability to extend the DIPJ Splint for 6-8 weeks. Surgery may be required if there is a large bone fragment or poor alignment

Question 45

What are some causes of EPL tendon rupture

Answer 45

RH, Fractures of the wrist, Gout, Systemic or local steroids

Question 46

What are the radiological features of RA

Answer 46

Joint space narrowing, joint erosions, periarticular cysts, soft tissue swelling

Question 47

Name some more deformities of the hand in RH

Answer 47

Boutonniere deformity and swan neck Subluxation

Question 48

What is the origin of the median nerve

Answer 48

It originates from the lateral and medial cords of the BP C5-T1

Question 49

Where does the ulnar nerve originate

Answer 49

Medial part of the brachial plexus

Question 50

Describe the vascular segments of the liver

Answer 50

The liver is divided into 8 segments, each segment receives a branch of the heaptic artery, portal vein and a bile ductile Segment 1-4 is considered the right lobe and 5-8 is considered the left lobe

Question 51

What are the contents of the axilla

Answer 51

Axillary artery and vein Lymph nodes 3 levels (level 1 is below, 2 is behind and 3 is above) Brachial plexus Fat

Question 52

What is the clavicopectoral fascia

Answer 52

The clavipectoral fascia is a thin layer of fibrous tissue that surrounds the pectoralis minor muscle. It attaches superiorly to the clavicle and inferiorly to the axillary fascia. It is thus the suspensory ligament of the axilla below the pectoralis minor. Four structures pierce the clavipectoral fascia. Two structures pass in: * cephalic vein * lymphatic vessels. Two structures pass out: * lateral pectoral nerve * thoracoacromial

Question 53

What are the boundaries of the cubital fossa

Answer 53

The cubital fossa is a triangular intermuscular space bounded: * superiorly by a line connecting the medial and lateral epicondyles of the humerus * medially by pronator teres * laterally by brachioradialis. The floor of the cubital fossa is formed from the brachialis and supinator muscles. The roof of the cubital fossa is made by the bicipital aponeurosis

Question 54

Boundaries of the cubital tunnel

Answer 54

The cubital tunnel has a roof formed by the aponeurotic expansion of the two heads of flexor carpi unaris. This spans in an arcade from the medial epicondyle of the humerus to the olecranon process of the ulna. The floor is formed by the medial collateral ligament of the elbow, expanding from the medial border of the olecranon to the base of the epicondyle.

Question 55

How is bowstringing of the tendons in the hand prevented

Answer 55

To prevent the flexor tendons from bow-stringing, there are a series of fascial coverings that anchor the tendon to the bony skeleton, while still allowing the tendons to glide smoothly. At the wrist there is the flexor retinaculum and on the fingers there are the annular (A1–5) and cruciate (C1–3) pulleys

Question 56

How can you test the flex dig sup and prof

Answer 56

The flexor digitorum profundus tendon inserts into the base of the distal phalanx of the finger. It can be tested by asking the patient to flex the distal interphalangeal joint of that finger. The flexor digitorum superficialis tendon inserts into the base of the middle phalanx of the finger. Flexion at the proximal interphalangeal joint can be by contraction of both the flexor digitorum superficialis and the flexor digitorum profundus; to test the function of the flexor digitorum superficialis muscle alone, the patient’s flexor digitorum profundus must be inactivated by holding their other fingers out straight and asking the patient to flex their unrestrained finger at the proximal interphalangeal joint. (Remember ‘the superficialis splits in two to allow profundus passing through’.)

Question 57

Which superficial flexor muscle is congenitally absent in around 10% of the population? What is the clinical significance of this

Answer 57

The palmaris longus is absent in around 10% of the population. This muscle has no real functional significance and can therefore be used as a tendon graft. Before harvesting this tendon graft it is wise to test for its presence while the patient is still awake. Ask the patient to make the V-sign with their index and middle fingers and then slowly flex their wrist. The palmaris longus tendon is visible as a separate line just on the ulnar side of the flexor carpi radialis tendon.

Question 58

What gives attachment to the flexor retinaculum

Answer 58

The flexor retinaculum attaches to the: L hook of the hamate and the pisiform on the ulnar aspect (HAMPISS) L lateral ridge of trapezium and the tubercle of the scaphoid on the radial aspect. (TRAPSCAPH)

Question 59

Which intrinsic muscles of the hand are not supplied by the ulnar nerve

Answer 59

lateral two lumbricals, opponens pollicis, abductor pollicis brevis and flexor pollicis brevis (‘LOAF muscles’), which are supplied by the median nerve

Question 60

What is the action of the lumbricals

Answer 60

They flex the metacarpophalangeal joint and extend the interphalangeal joints.

Question 61

What is a duputreyns contracture

Answer 61

The palmar aponeurosis seems to be susceptible to progressive hyperplasia and fibrosis, with subsequent thickening and shortening. This leads to a flexion deformity of one or more of the digits, with associated loss of function. This condition is known as Dupuytren’s contracture. Trigger finger is different than this as it is a problem with the flexor pulley system

Question 62

Where are parts of the BP found

Answer 62

Roots: exits from IV foramina between scalenus anterior and medius * Trunks: base of the posterior triangle of the neck behind the 3rd part of the subclavian artery * Divisions: behind middle ⅓ of the clavicle * Cords: related to the 2nd part of axillary artery

Question 63

What are the different parts of the scapula

Answer 63

Question 64

What is the insertion and innervation of the rotor cuff muscles

Answer 64

Supraspinatus: Suprascapular nerve and GT of humerus Infraspinatus: Suprascapular nerve and GT of humerus Subscapularis: Upper and lower subscapular nerve and LT of humerus Teres minor: Axillary nerve and GT of humerus

Question 65

What are the structures that attach to the coracoid process

Answer 65

Ligaments o Coracoclavicular (trapezoid, conoid) o Coracoacromial o Coracohumeral * Muscles o Pectoralis minor (insertion) o Coracobrachialis (origin) o Short head of biceps (origin)

Question 66

What are the muscles in the bicipital groove

Answer 66

‘PLT sandwich’ or ‘Lady between 2 majors’ * Teres major (medial lip) * Latissimus dorsi (floor) * Pectoralis major (lateral lip)

Question 67

What is the upper end anatomy of the humerus

Answer 67

Question 68

Distal humeral anatomy

Answer 68

Question 69

Anatomical areas of the upper limb (bony landmarks)

Answer 69

Question 70

Anatomy of the radius and ulna

Answer 70

Question 71

What are the boundaries of the ulnar canal

Answer 71

* Medial (ulnar) – pisiform, flexor carpi ulnaris tendon, abductor digiti minimi muscle. * Lateral (radial) – hook of hamate. * Roof – palmar carpal ligament. * Floor – flexor retinaculum, pisohamate ligament, and hypothenar muscles.

Question 72

Explain the ulnar paradox

Answer 72

The ulnar paradox is a phenomenon that occurs when a high ulnar nerve lesion at the elbow causes less clawing than a low ulnar nerve lesion at the wrist. This is because a high lesion weakens both the hand muscles and the long flexors, while a low lesion only weakens the hand muscles. In a high lesion, the medial half of the flexor digitorum profundus (FDP) is paralyzed, which slackens the fourth and fifth interphalangeal joints. This relaxes the hand and reduces the claw-like appearance, instead paralyzing the fingers in an extended position. This is called the ulnar paradox because it's unexpected that a more proximal lesion would result in less deformity. As the patient recovers, reinnervation along the ulnar nerve can cause the deformity to worsen

Question 73

What is the blood supply to the acromioclavicular joint

Answer 73

* Suprascapular artery – arises from the subclavian artery at the thyrocervical trunk. * Thoracoacromial artery – arises from the axillary artery.

Question 74

What is the nerve supply to the sternoclavicular joint

Answer 74

The sternoclavicular joint is supplied by the medial supraclavicular nerve (C3 and C4) and the nerve to subclavius (C5 and C6).

Question 75

What holds the distal radio ulnar joint together

Answer 75

Triangular fibrocartilage