Clinical Anatomy of the Upper Limb

Question 1

2 joints of the shoulder girdle?

Answer 1

Glenohumeral (synovial)

Acromioclavicular (fibrous)

Question 2

Stabilisers of the shoulder?

Answer 2

Capsule

Rotator cuff (pull the humeral head into the glenoid fossa) and other muscles

Labrum (ring of cartilage)

Question 3

What is painful arc syndrome?

Answer 3

AKA shoulder impingement syndrome

Tendons of the rotator cuff muscles become inflamed (tendonitis) as they pass through the subacromial space (beneath the acromion); so, anything causing narrowing of the space can cause this syndrome

Result is:
• Tendonitis
• Cuff tears
• Subacromial bursitis
• Osteophytes from the AC joint

Question 4

Symptoms of painful arc syndrome?

Answer 4

Pain, weakness and loss of movement at the shoulder

Question 5

Treatment of painful arc syndrome?

Answer 5

Injection of subacromial space

Question 6

Describe Bankart lesion

Answer 6

Injury of the anterior, inferior glenoid labrum of the shoulder (commonly detaches), due to anterior shoulder dislocation; a pocket forms at the front of the glenoid that allows the humeral head to dislocate into it

Question 7

Treatment of Bankart lesion?

Answer 7

If the person has recurrent dislocation, it can be repaired

Question 8

Injuries assoc. with anterior shoulder dislocation?

Answer 8

Axillary nerve is most common nerve injury; it is stretched at the quadrangular space

Also, there can be compression of the brachial plexus and axillary artery

Question 9

Which type of shoulder dislocation is most common?

Answer 9

Anterior dislocation

Posterior dislocations account for only 1%

Question 10

Order of the brachial plexus (mnemonic)?

Answer 10

Roots

Trunks

Divisions

Cords

Terminal branches (peripheral nerves)

Ron Taylor Drinks Cold Beer

Question 11

What is adhesive capsulitis?

Answer 11

AKA frozen shoulder - unclear cause but the shoulder capsule and connective tissue surrounding the glenohumeral joint becomes inflamed and stiff

Leads to a global loss of ROM (especially external rotation)

Question 12

Treatment of frozen shoulder?

Answer 12

In the painful phase, the glenohumeral joint can be injected

Question 13

Describe injury of the coracoclavicular ligaments

Answer 13

If ruptured, with AC joint dislocation or clavicle fracture, displacement can occur

Question 14

Nerve supply to the anterior compartment?

Answer 14

Musculocutaneous nerve (also supplies sensation to the lateral forearm)

Question 15

Nerve supply to the posterior compartment?

Answer 15

Radial nerve

Question 16

Scenarios where the radial nerve can be injured?

Answer 16

Susceptible to injury in humeral shaft fractures; as it supplies the extensors of the upper limb, this can cause wrist drop

Question 17

Most powerful flexor of the arm?

Answer 17

Brachialis

Question 18

Most powerful supinator of the wrist?

Answer 18

Biceps femoris

Question 19

Elbow joints?

Answer 19

Humero-ulnar joint

Radio-capitellar joint (allow supinator and pronation, along with the radioulnar joints)

Question 20

Common extensor origin of the elbow?

Answer 20

Lateral epicondyle (inflamed in Tennis elbow)

Question 21

Common flexor origin of the elbow?

Answer 21

Medial epicondyle (Golfer’s elbow)

Question 22

Complications of a supracondylar fracture of the elbow?

Answer 22

Brachial artery occlusion and median nerve injury (radial and ulnar nerves may also be injured)

Question 23

Symptoms of s supracondylar fracture of the elbow?

Answer 23

Common in children who fall onto an outstretched hand

Pale hand and no pulse - emergency reduction and checking for a return of the pulse

Question 24

Joints of the forearm?

Answer 24

Proximal and distal radio-ulnar joints facilitate supination and pronation of the forearm; there are strong ligaments at either end

Question 25

2 types of fracture dislocations of the forearm?

Answer 25

Monteggia fracture dislocation - fracture of the proximal 1/3rd of the ulna with dislocation of the head of the radius

Galeazzi fracture dislocation - fracture of the radius with dislocation of the distal radio-ulnar joint

Question 26

Nerve supply to the anterior compartment of the forearm?

Answer 26

Medican nerve, except for the flexor carpus ulnaris and the ulnar half of the flexor digitorum profundus (ulnar nerve)

Question 27

Nerve supply to the posterior compartment of the forearm?

Answer 27

Radial nerve

Question 28

General rule for nerve supply to extensors of the upper limb?

Answer 28

Radial nerve supply

Question 29

Shapes of the various carpal bones?

Answer 29

Scaphoid is kidney-bean shaped

Lunate is roughly spherical

Hamate has a hook

Question 30

Describe scaphoid fractures

Answer 30

Can lead to avascular necrosis

Many fractures do not appear on the 1st X-ray; so, bring patients back in a few weeks and the X-ray should show resorption of bone

Question 31

Boundaries of the carpal tunnel?

Answer 31

Carpal bones and the flexor retinaculum (AKA transverse carpal ligament)

Question 32

Names of the hand digits?

Answer 32

Thumb

Fingers:
• Index
• Middle
• Ring
• Pinky

Question 33

What is the palmar fascia?

Answer 33

AKA palmar aponeurosis, invests the muscles of the palm

Question 34

What is trigger finger and what causes it?

Answer 34

Catching, snapping or locking of the involved finger flexor tendon, assoc. with dysfunction and pain; when the finger unlocks, it pops back suddenly, as if releasing a trigger on a gun

Disparity in size between the flexor tendon and the surrounding retinacular pulley system, most commonly at the level of the first annular pulley, results in difficulty flexing/extending the finger; can be caused by nodules

Question 35

Intrinsic muscles of the hand and nerve supply?

Answer 35

Thenar muscles and the lateral 2 lumbricals

• LOAF (lumbricals 1 & 2, Opponens pollicis, Abductor pollicis brevis and Flexor pollicis brevis) - median nerve
• Rest of the intrinsic muscles of the hand are supplied by the ulnar nerve

Question 36

Muscles allow flexion of the fingers?

Answer 36

Flexor digitorum superficialis allows flexion of the PIPJ and MCPJ

Flexor digitorum profundus allows flexion of the DIPJ

Question 37

Muscles allowing extension of the fingers?

Answer 37

Central slip extensor tendon allow PIPJ extension

Lateral slip’s extensor tendon coverage allows DIPJ extension

Question 38

Muscle allowing flexion and extension of the fingers?

Answer 38

Intrinsics (interossei & lumbricals) insert into the lateral bands and contribute to flexion at MCPJ and extension at PIPJ

Question 39

Describe Boutonniere deformiry

Answer 39

Central slip extensor tendon rupture or attrition causes permanent PIP flexion and DIP extension

Seen in RA

Question 40

Describe swan neck deformity

Answer 40

PIPK volar plate rupture or attrition causes intrinsic muscle tightness and permanent DIP flexion with PIP hyperextension

Seen in RA

Question 41

Testing motor function of the median nerve and anterior interosseous branch?

Answer 41

Adductor Pollicis Brevis with examiners hand over the thenar muscles from the first web

If there is a lesion and the patient is asked to make an “OK” sign (Flexor Pollicis Longus and Flexor Digitorum Profundus to the index finger), they will make a triangle sign instead

Question 42

Testing sensory and motor function of the ulnar nerve?

Answer 42

Sensory - feel the 1st dorsal interosseous

Motor - Froment’s test looks at function of adductor pollicis

Question 43

Testing function of the radial nerve?

Answer 43

If there is a high lesion, triceps function can be assessed by asking the patient to extend the elbow against resistance

If lesion is above the elbow, check for wrist drop

If lesion is below the elbow, check for a finger or thumb drop