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LO: Topographical and Surface Anatomy of Bones and Joints of the Upper Limb
Basic Anatomical Structures and Principles (syllabus)
Understand the concepts and associated principles, functional and clinical applications of the
topographical anatomy of the bones, joints and muscles of the upper limb.
Surface and functional anatomy (syllabus)
Understand and explain the relevant surface and functional anatomy of the bones, joints and
muscles of the upper limb.
Shoulder Complex
Palpate and draw on each other the following bony landmarks:
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sternoclavicular joints, acromioclavicular joints, shaft of clavicles
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Acromion, spine, corocoid process, medial border, inferior angle of scapula
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Greater and lesser tubercles of the humerus
(This is the humerus of the left
arm – the greater tubercle will
always be more lateral than the
lesser tubercle)
Demonstrate the movements of the scapula (noting the muscle groups producing each);
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Pectoralis Minor: With ribs fixed, draws scapula forwards and downwards (with scapula
fixed, it will draw the ribs superiorally)
Serratus Anterior: Prime mover to protract and hold scapula against chest wall; rotates
scapula so its inferior angle moves laterally and upwards; raises point of shoulder; important
role in abduction and raising of arm and in horizontal arm movements
Trapezius: Stabilises, raises, retracts and rotates scapula. Middle fibres retract causing
adduction of the scapulae. Superior fibres retract causing elevation of the scapulae. Can also
help to extend the head by retraction of the inferior fibres, which pull (or depress) the
scapulae
Levator Scapulae: Elevates/adducts in concert with the superior fibres of the trapezius (also
tilts glenoid cavity downwards when scapula is fixed, flexes neck to the same side)
Rhomboids: Act together (and with middle traps) to retract scapula (square the shouldars);
rotate glenoid cavity downwards (when arm is lowered against resistance) and helps to
stabilise the scapula
Assess the shoulder joint by the steps of:
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Inspection
Look for swellings, scars, asymmetry, redness
Palpation

Fell for tenderness and swelling. Move the joint and feel the AC joint, the clavicle and the SC
joint
Movements: noting the muscle groups producing each
Abduction – usually possible to 90 degrees
Elevation – usually possible to 180 degrees
Adduction – usually possible to 50 degrees
External rotation – usually possible to 65 degrees
Internal rotation – usually possible to 90 degrees
Flexion – usually possible to 180 degrees
Extension – usually possible to 65 degrees
Explain to role of ‘rotator cuff’ muscles

Rotator muscles are the Supraspinatus, Infraspinatus, Teres minor, Subscapularis (SITS)
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Subscapularis: Chief medial rotator of the humerus (assisted by pec major). Also
helps to hold the head of the humerus in the glenoid cavity, thereby stabilising the
shoulder joint
Supraspinatus: Stabilises shoulder joint and helps to prevent downward dislocation
of the humerus. Also assists with abduction
Infraspinatus: Rotates humerous laterally and also helps to hold the head of the
humerus in the glenoid cavity
Teres minor: same action as the infraspinatus, but also adducts arm
Elbow Complex
Palpate and draw on each other the following bony landmarks;

head, dorsal tubercle, styloid process of radius

Olecranon process, posterior border of
shaft, head, styloid process of ulna
Assess the elbow joints by the steps of:
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Inspection
Look for swellings, scars, asymmetry, redness
Palpation
Feel for tenderness, especially over the lateral epicondyles. Palpate for any discreet
swellings
Movements: noting the muscle groups producing each
Move the elbow joint passively. Normal flexion is possible to 150 degrees
Demonstrate the ‘carrying angle’
With the arms extended at the sides and the palms facing forward, the forearm and hands are
normally slightly away from the body. This is the normal "carrying angle" of the elbow, which is 5 to
15 degrees. This angle permits the forearms to clear the hips in swinging movements during walking,
and is important when carrying objects.
The carrying angle permits the arm to be swung without contacting the hips. Women on average
have smaller shoulders and wider hips than men, which may necessitate a greater carrying angle.
There is, however, extensive overlap in the
carrying angle between individual men and
women, and a sex-bias has not been
consistently observed in scientific studies.
Demonstrate the Movements of the radio-ulner joint (noting the muscle groups producing each)
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Triceps brachii: Primary forearm extensor and antagonist of forearm flexors
Anconeus: Abducts ulna during forearm pronation; synergist of triceps brachii in elbow
extension
Biceps brachii: flexes elbow joint and supinates forearm (also weak flexor of arm at the
shoulder)
Brachialis: Major forearm flexor (lifts ulnar as biceps lift the radius)
Brachioradialis: Synergist in forearm flexion; acts to best advantage when forearm is partially
flexed and semi-pronated. During rapid extension and flexion, it also works to stabilise the
elbow
Palpate the following;
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tendon of biceps in the cubital fossa
bicipital aponeurosis
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olecranon bursa
Wrist and Hand
Palpate and draw on each other the following bony
landmarks;
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Tubercle of scaphoid and crest of trapezium
Pisiform bone and hook of hamete
Heads of metacarpals
Draw in the flexor retinaculum (noting relationship with the
distal skin crease of the wrist)
Palpate the bones forming the floor of the “anatomical snuff box” noting in particular the scaphoid
bone)
(Scaphoid is the major bone of the floor of the
anatomical snuff box)
Assess the wrist joint by the steps of;
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Inspection
Erythema, atrophy, scars and rashes, inflammation, deformity,
Palpation
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Feel gently for synovitis (boggy swelling) and effusions. Dorsifex and palmar flex, then test
ulnar and radial deviations, noting any tenderness, limitation or joint crepitus
Movements: noting the muscles groups producing each
Flexor carpi radialis: Flexor of wrist, abducts hand (and weak synergist of elbow flexion)
Palmaris longis: Weak wrist flexor, tenses skin and fascia of hand during movements (and
weak synergist of elbow flexion)
Flexor carpi ulnaris: Flexes and adducts hand at wrist
Flexor digitorum superficialis: Flexes wrist and middle phalanges of fingers 2-5
Flexor digitorum profundis: Flexes distal phalanges 4 and 5 at distal interphalangeal joints
and assists in wrist flexing
Extensor carpi radialis longus: Extend and abduct hand at the wrist joint; ECRL active during
fist clenching
Extensor carpi radialis brevis: Same as above
Extensor digitorum: Extends wrist (and is the prime mover of finger extension)
Extensor carpi ulnaris: Extends and adducts hand at wrist joint (active during fist clenching)
Abductor pollicus longis: Abducts wrist
Demonstrate (noting the muscle groups producing each):
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Movement of the thumb
Flexor pollicus longis (FPL): Flexes phalanges of thumb
Abductor pollicis longus (APL): Abducts thumb and extends it at carpometacarpal joint
Extensor pollicis longus (EPL): Extends distal phalanx of thumb at interphalangeal joint; extends
metacarpophalangeal and carpometacarpal joints
Extensor pollicus brevis: Extends proximal phalanx of thumb at metacarpophalangeal joint;
extends carpometacarpal joint
Opponens pollicis: To oppose thumb, it draws 1st metacarpal medially to centre of palm and
rotates it medially
Abductor pollicis brevis: Abducts thumb; helps oppose it
Flexor pollicis brevis: Abducts thumb; helps oppose it
Flexor pollicis brevis: Flexes thumb
Superficial head, Deep head, adductor pollicus, oblique head and transverse head: Adducts
thumb toward lateral border of palm
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Movements of the fingers
Flexor digitorum superficialis (FDS), Humeroulnar head and Radial head: Flexes middle
phalanges at proximal interphalangeal joints of the middle four fingers; acting more strongly,
it also flexes proximal phalanges at metacarpophalangeal joints
Extensor digitorum: Extends medial 4 fingers primarily at metacarpophalangeal joints,
secondarily at interphalangeal joints
Extensor digiti minimi (EDM): Extends 5th finger primarily at the metacarpophalangeal joint,
secondarily at interphalangeal joint
Extensor indicis: Extends 2nd finger (enabling its independent extension); helps extend wrist
at hand
Abductor digit minimi: Abducts 5th finger and assists in flexion of its proximal phalanx
Flexor digiti brevis: Flexes proximal phalanx of 5th finger
Opponens digit minimi: Draws 5th metacarpal anterior and rotates it, bringing 5th finger into
opposition with thumb
Lumbricals (1st – 4th): Flex metacarpophalangeal joints; extend interphalangeal joints of 2nd
– 5th fingers
Dorsal interossei, 1st – 4th: Abduct 2nd – 4th fingers from axial line; act with the lumbricals
in flexing metacarpophalangeal joints and extending interphalangeal joints
Palmar interossei 1st – 3rd: Adduct 2nd, 4th and 5th fingers towards axial line; assist
lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints;
extensor expansions of 2nd – 4th fingers
Explain the role of the dorsal digit expansion in movements of the fingers;
The functional significance of the dorsal digit expansion is to allow the complex movements
of the fingers to occur. For example, writing involves the flexing of some joints and extension
of others and therefore a balance between flexors and extensors is necessary.
Palpate the tendons at the front and back of the wrist;