Elbow, Forearm, Wrist and Hand

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Elbow, Forearm, Wrist and
Hand
Elbow
Bones:
–Humerus: only bone of the arm
Landmarks: medial and lateral
epicondyles, olecranon fossa,
capitulum (articulation with the
radius), trochlea (articulation with the
ulna)
Ulna: bone on the pinkie (medial) side of
forearm
– Landmarks: olecranon process, radial notch
Radius: bone on the thumb (lateral) side of
forearm
– Landmarks: radial head
Ligaments:
– Ulnar collateral: prevents valgus force
(think of it as MCL of knee)
– Radial collateral: prevents varus force
(think of it as LCL of knee)
– Annular ligament: circular ligament
encompassing the radius, allows for
rotation of radius while holding it
securely to the ulna
Bursae
–Bicipital bursa: anterior aspect
of elbow, cushions the bicep
–Olecranon bursa: posterior
aspect of elbow, cushions
between olecranon process and
the skin
Muscles
–Elbow flexion
Brachialis, brachioradialis, biceps
brachii
–Elbow extension
Triceps brachii
Nerves:
–Ulnar nerve: passes posterior to the
medial epicondyle “hitting your
funny bone”
Joint Mechanics
–Elbow: hinge joint between ulna
and humerus
Allows for flexion and extension
–Joint between ulna and radius
(radio-ulnar)
Allows for pronation and
supination of the forearm
Forearm
Bones: Radius and ulna held
together by interosseus
membrane
–Landmarks: radial and ulnar styloid
processes
Radioulnar joint
–Proximal allows for pronation
and supination
–Distal connects the radius and
ulna at the wrist
Muscles
Anterior (flexors)
– Flexor digitorum superficialis
– Flexor digitorum profundus
– Flexor carpi ulnaris
– Flexor carpe radialis
– Flexor pollicus longus
– Pronator teres
** flexor tendons originate on the medial
epicondyle of the humerus
Muscles cont.
Posterior (extensors)
– Extensor digitorum communis
– Extensor carpi radialis longus
– Extensor carpi radialis brevis
– Extensor carpi ulnaris
– Extensor pollicus longus
** extensors origiante on the lateral epicondyle
of the humerus
Wrist and Hand
Basic Anatomy
– Bones
Distal radius and ulna (styloid process)
Carpals: 8 bones of wrist
– Scapoid, lunate, triquetrum, pisiform, trapezium,
trapezoid, capitate, hamate
Metacarpals: 5 bones of hand
Phalanges: 14 bones of fingers
Carpal tunnel: tunnel formed by carpal
bones and closed off by the transverse
carpal ligament. Nerves, blood vessels
and muscles pass through this tunnel.
Wrist joint: joint between distal radius and
ulna and the carpal bones
– Movements: flexion, extension, radial and
ulnar deviation
Joints of Fingers and Hand
Carpometacarpal joint (CM)
Metacarpo-phalangeal (MP)
Interphalangeal (IP)
– Proximal Interphalangeal (PIP)
– Distal Interphalangeal (DIP)
Ligaments of Wrist
Ulnar collateral: from styloid process of
wrist to triquetrum
Radial collateral: from styloid process of
radius to scaphoid
Transverse carpal ligament: closes off
carpal tunnel
Muscles and Tendons
The extrinsic muslces and tendons of the
hand and fingers originate in the forearm.
See the muscles listed for the forearm
Muscles of the thumb
– Extensor pollicus longus
– Extensor pollicus brevis
– Abductor pollicus longus
– Flexor pollicus brevis
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