Upper Limb I

Question 1

Surface anatomy of the breast

Answer 1

Breast overlies 2nd and 6th rib. 2/3 overlies pec major and lower 1/3 over serratus anterior with the medial lower aspect over the upper rectus sheath

Question 2

Ligaments of cooper and general breast structure

Answer 2

15-20 lobules separated by fibrous septa running from subcut tissue to fascia (Ligaments of Cooper)

Each lobule drains via lactiferous duct into the areola which is surrounded by glands of montgomery (Sebacious glands)

Question 3

Blood supply of the breast

Answer 3

Axillary artery via lateral thoracic and acromiothoracic branches

Internal thoracic (internal mammary artery) via perforating branches through 1-4 intercostal spaces

Question 4

Lymph drainage

Answer 4

Axillary lymph nodes

Follows internal thoracic arteries to the internal mammary chain

Lateral part of breast tends to drain to axilla
Medial part of breast tends towards the internal mammary chain

Metastasis:
level I: inferior to pec minor
level II: behind pec minor
level III: above pec minor

Question 5

Pisiform, hamate, scaphoid

Answer 5

Pisiform at base of the hypothenar eminence-flexor carpi ulnaris attaches here

Hamate distal to pisiform. Scaphoid base of the thena eminence and anatomical snuff box

Question 6

Wrist (Volar)

Answer 6

1. Radial pulse
2. Lateral to RP is flexor carpi radialis then palmaris longus (can be absent)
3. Flexor digitorum superficialis tendon cluster
4. Flexor carpi ulnaris lies medially and inserts into the pisiform
5. Ulna pulse is to the radial side of flexor carpi ulnaris

Question 7

Wrist (dorsal)

Answer 7

Anatomically lateral to medial:
Abductor pollicis longus
Extensor pollicis brevis
extensor carpi radialis longus and brevis
extensor indicis
extensor digitorum
extensor digiti minimi
extensor carpi ulnaris

Question 8

Anatomical snuff box

Answer 8

Abductor pollicis longus
Extensor pollicis brevis (laterally)
Extensor pollicis longus-medially towards ulnar side (trace to the base of the terminal phalanx of thumb)

Question 9

Vessels in the upper arm to wrist: General

Answer 9

Arch of the aorta:
(R)–>brachiocephalic branch and then R subclavian artery
(L) Left subclavian artery is a direct branch of the aortic arch
Subclavian artery->axillary artery->Brachial artery—>radial and ulnar artery

Question 10

Subclavian artery branches

Answer 10

3 parts with 1) 3 branches 2) 2 branches 3) 0

Question 11

Subclavian artery 1st part

Answer 11

medial to scalenus anterior 
arches over suprapleural membrane
3 branches:
- Vertebral
- internal thoracic
- Thyrocervical trunk

Question 12

Subclavian artery 2nd part

Answer 12

Behind scalenous anterior
2 branches:
Costocervical: (Deep cervical and superior intercostal)
Dorsal scapular

Question 13

Subclavian artery 3rd part

Answer 13

Lateral to scalenus and anterior to the 1st rib

No further branches

Question 14

Axilary artery becomes the brachial artery…

Answer 14

…..brachial becomes radial and ulna

Question 15

Veins: Route from hand I

Answer 15

Dorsal venous network on dorsum of hand culminates in the lateral cephalic close relation to the radial styloid) and medial basilic vein.

Question 16

Veins: Route from hand II cephalic vein

Answer 16

Cephalic vein progresses up the arm to lie in the lateral groove of the biceps then pierces the deep fascia to lie in the groove between pec major and the deltoid before joining the axillary vein.

Question 17

Veins: Route from hand III basilic vein

Answer 17

Travels posteromedially along arm up to the axillary vein

It is linked to the cephalic vein by median cubital vein

Question 18

Nerves in upper arm (5)

Answer 18

1) Axillary
2) Radial
3) Posterior interosseous nerve a branch of radial
4) Ulnar
5) Median

Question 19

Axillary nerve

Answer 19

1) The axillary nerve is related closely to the surgical neck of the humerus 2 inches (5 cm) below the acromion process.

Question 20

Radial nerve

Answer 20

2) The radial nerve crosses the posterior aspect of the humeral shaft at its mid-point.

Question 21

Radial nerve post interosseous branch

Answer 21

3) The posterior interosseous branch of the radial nerve is located by Henry’s method as it winds round the radius. Place three fingers along the radius, the uppermost lying just distal to the radial head; the 3rd finger then lies over this nerve.

Question 22

Median Nerve

Answer 22

4) The median nerve in the forearm lies, as its name suggests, in the median plane; its area of distribution in the hand is thus anaesthetized if local anaesthetic be injected exactly in the mid-line at the wrist.

Question 23

Ulnar nerve

Answer 23

5) The ulnar nerve at the wrist lies immediately medial to the ulnar pulse. In the hand, it passes on the radial side of the pisiform and then lies on the hook of the hamate. If you press with your fingernail just lateral to the pisiform bone, you will experience tingling in your ulnar two fingers.

Question 24

Axilary artery relations

Answer 24

1st part; 1st rib
2nd part: Behind pec minor
3rd part: Teres major

Question 25

Axilary artery branches: | Sometimes life seems a pain

Answer 25

``` Superior thoracic artery (I) Thoracoacromial artery(II) Lateral thoracic artery (II) Subscapular artery (III) Anterior circumflex artery (III) Posteror circumflex artery (III) ```

Question 26

Which of the following is true of the musculocutaneous nerve? (Please select 1 option) Is a branch of the lateral cord of the brachial plexus CorrectCorrect Leaves the plexus at the point at which it crosses the first rib None of the above Only contains sensory fibres Receives fibres from the 8th cervical spinal root

Answer 26

The musculocutaneous nerve is the major terminal branch of the lateral cord of the brachial plexus. The lateral cord contains fibres from the superior and middle trunks which represent the spinal roots of the 5th to 7th cervical vertebrae. It leaves the plexus as the cords give off their branches to the major nerves of the arm. The cords correspond to the point at which the plexus emerges from behind the clavicle. It courses the axilla in the coracobrachialis muscle, and then descends obliquely and laterally between the biceps and brachialis muscles, sending motor fibres to all of these. It terminates in the forearm as the lateral antebrachial cutaneous nerve supplying sensation to the lateral aspect of the forearm.

Question 27

Which of the following structures accompany the median nerve in the carpal tunnel? (Please select 1 option) All of the above. IncorrectIncorrect answer selected Flexor carpi ulnaris. Flexor digitorum profundis. This is the correct answerThis is the correct answer None of the above. The ulnar artery.

Answer 27

The carpal tunnel is an osseofibrous tunnel formed by the flexor retinaculum in the wrist. The median nerve and tendons of the long flexor muscles of the digits pass through it.

Question 28

The nerve most at risk from a fracture of the medial epicondyle of the humerus.

Answer 28

Ulnar nerve The ulnar nerve (C7, 8, T1) is most often injured behind the elbow. Here it runs in a groove in the medial epicondyle of the humerus. It can also be injured at the wrist where it crosses the flexor retinaculum lateral to the pisiform bone.

Question 29

Injury to this nerve produces paralysis of the thenar muscles.

Answer 29

Median nerve The muscular recurrent branch of the median nerve curves around the distal border of the flexor retinaculum to supply the three thenar muscles: abductor and flexor pollicis longus and opponens pollicis. This branch is at risk during carpal tunnel release.

Question 30

This nerve is at risk from cannulation of the blood vessels in the antecubital fossa.

Answer 30

Median nerve | In the antecubital fossa the median nerve lies medial to the brachial artery beneath the bicipital aponeurosis.

Question 31

Examination reveals loss of extension of the metacarpophalangeal joints and loss of sensation to the skin over both the radial side of the dorsum of the hand and the anatomical snuffbox.

Answer 31

Radial nerve in forearm After mid forearm injuries of the radial nerve, the innervation to the extensor carpi radialis longus muscle is preserved via the posterior interosseous nerve, which branches off in the cubital fossa before the posterior interosseous nerve pierces the supinator muscle. Thus, although there is weakness of wrist extension, wrist drop is thereby avoided.

Question 32

Examination reveals an inability to adduct and abduct the fingers, positive Froment's sign, loss of sensation of the medial one and a half digits and 'clawing' of the ring and little fingers.

Answer 32

Ulnar nerve injury at the wrist After mid forearm injuries of the radial nerve, the innervation to the extensor carpi radialis longus muscle is preserved via the posterior interosseous nerve, which branches off in the cubital fossa before the posterior interosseous nerve pierces the supinator muscle. Thus, although there is weakness of wrist extension, wrist drop is thereby avoided. Ulnar nerve injury at the wrist causes paralysis of the intrinsic muscles of the hand with wasting of the interossei and hypothenar muscles. Froment's sign is loss of adduction of the thumb (the patient tries to flex distal interphalangeal [DIP] of thumb instead). The long digital flexor muscles are unopposed by the lumbrical and interossei muscles, producing flexion of DIP and proximal interphalangeal joint (PIP) joints. Pull on the long digital extensor tendons produces hyperextension of the metacarpophalangeal (MCP) joints and clawing. With elbow injuries, paralysis of the flexor carpi ulnaris and ulnar half of flexor digitorum profundus (FDP) muscles results in loss of long digital flexion and less clawing.

Question 33

A 22-year-old woman presents to the emergency department on a Sunday after falling on her outstretched hand after drinking alcohol the previous evening. She complains of pain in her right hand and wrist. There is no obvious deformity. She is tender when you press in the anatomical snuffbox and pull on her thumb. What is the most appropriate set of x rays to ask the radiographer to perform? (Please select 1 option) x Ray forearm (screening x ray) x Ray hand x Ray scaphoid views x Ray thumb x Ray wrist

Answer 33

x Ray scaphoid views The most likely bone to be fractured is the scaphoid bone. The scaphoid bone is one of the eight carpal bones. The others are the ``` Lunate Triquetral Pisiform Hamate Capitate Trapezium Trapezoid. It is important to suspect a fracture of the scaphoid because as well as being the most commonly fractured carpal bone, it also has a high risk of undergoing avascular necrosis when fractured. ``` It should also be noted that scaphoid fractures can be difficult to see even with scaphoid views. If a fracture is suspected, the patient should be treated as if they have fractured the bone even if not conformed radiologically. Missed scaphoid fractures are a common cause of litigation.

Question 34

You are an orthopaedics SHO assisting your registrar in a local anaesthetic day surgery list. The first case is a carpal tunnel decompression. After the patient has been positioned, anaesthetised, cleaned and draped your registrar makes the skin incision. This is in the palm from the base of the thenar eminence in a line towards the radial border of the ring finger down to the transverse flexor skin incision of the wrist (proximal limit). What is the first tendon that is seen beneath the fat? (Please select 1 option) Flexor carpi radialis Flexor carpi ulnaris Flexor digitorum profundus Flexor digitorum superficialis Palmaris longus

Answer 34

Palmaris longus This is the correct answerThis is the correct answer Palmaris longus is usually the first tendon that is seen, although it is absent in approximately 10% of the population. The palmaris longus originates from the medial epicondyle of the humerus and attaches to the distal half of the flexor retinaculum and palmar aponeurosis. Its innervation is via the median nerve. It helps to flex the hand. The tendons of the ``` Flexor digitorum profundus Flexor digitorum superficialis Flexor carpi radialis and Flexor pollicus longus travel in the carpal tunnel. ``` The median nerve also is also transmitted in the carpal tunnel.

Question 35

An orthopaedic surgeon is operating on a shoulder following an anterior dislocation. She uses an anterior approach to gain access to the shoulder joint. This involves exposing the deltopectoral groove as the landmark for entry. What structure will be seen running between these two muscles? (Please select 1 option) Axillary artery Axillary vein Cephalic vein Median nerve Nerve to pectoralis major

Answer 35

Cephalic vein The cephalic vein will be seen in the deltopectoral groove. It does not need to be ligated, but is retracted. The cephalic vein originates at the radial styloid. It runs up the forearm to lie initially on the lateral side of the biceps. It joins the axillary vein after running through the clavipectoral fascia. The axillary artery and median nerve run deep to the muscles.

Question 36

``` A 46-year-old man is being investigated in the vascular clinic for thoracic outlet syndrome. Which important structure passes anterior to the scalene tubercle on the first rib? (Please select 1 option) Scalenus medius Subclavian artery Subclavian vein Superior intercostal artery Sympathetic trunk ```

Answer 36

Subclavian vein

Question 37

Which of the following nerves is responsible for innervation of the triceps muscle? ``` A. Radial B. Ulnar C. Axillary D. Median E. None of the above ```

Answer 37

To remember nerve roots and their relexes: 1-2 Ankle (S1-S2) 3-4 Knee (L3-L4) 5-6 Biceps (C5-C6) 7-8 Triceps (C7-C8) The radial nerve innervates all three heads of triceps, with a separate branch to each head.

Question 38

Which of the following statements relating to the root of the neck is false? A. The lung projects into the neck beyond the first rib and is constrained by Sibson's fascia B. The subclavian artery arches over the first rib anterior to scalenus anterior C. The roots and trunks of the Brachial plexus lie posterior to the subclavian artery on the first rib D. The roots and trunks of the Brachial plexus lie between scalenus anterior and scalenus medius muscles E. The thyrocervical trunk is a branch of the subclavian artery

Answer 38

The subclavian artery arches over the first rib anterior to scalenus anterior The subclavian artery lies posterior to scalenus anterior, the vein lies in front. Sibson's fascia is another name for the suprapleural membrane. Thoracic Outlet Where the subclavian artery and vein and the brachial plexus exit the thorax and enter the arm. They pass over the 1st rib and under the clavicle. The subclavian vein is the most anterior structure and is immediately anterior to scalenus anterior and its attachment to the first rib. Scalenus anterior has 2 parts, the subclavian artery leaves the thorax by passing over the first rib and between these 2 portions of the muscle. At the level of the first rib, the lower cervical nerve roots combine to form the 3 trunks of the brachial plexus. The lowest trunk is formed by the union of C8 and T1, and this trunk lies directly posterior to the artery and is in contact with the superior surface of the first rib. Thoracic outlet obstruction causes neurovascular compromise.

Question 39

A patient presents to the clinic following a surgical procedure. She complains that she is unable to shrug her shoulder. What is the most likely underlying nerve injury? ``` A. Accessory nerve B. Cervical plexus C. Ansa cervicalis D. Long thoracic nerve E. Axillary nerve ```

Answer 39

The accessory nerve may be injured in operations in the posterior triangle. Injury will affect trapezius.

Question 40

Which of the following muscles inserts onto the lesser tuberostiy of the the humerus? ``` A. Subscapularis B. Deltoid C. Supraspinatus D. Teres minor E. Infraspinatus ```

Answer 40

With the exception of subscapularis which inserts into the lesser tuberosity, the muscles of the rotator cuff insert into the greater tuberosity.

Question 41

A 73 year old lady suffers a fracture at the surgical neck of the humerus. The decision is made to operate. There are difficulties in reducing the fracture and a vessel lying posterior to the surgical neck is injured. Which of the following is this vessel most likely to be? ``` A. Axillary artery B. Brachial artery C. Thoracoacromial artery D. Transverse scapular artery E. Posterior circumflex humeral artery ```

Answer 41

Posterior circumflex humeral artery The circumflex humeral arteries lie at the surgical neck and is this scenario the posterior circumflex is likely to be injured. The thoracoacromial and transverse scapular arteries lie more superomedially. The posterior circumflex humeral artery is a branch of the axillary artery.