1
2
In two layers:
a superficial layer
a deep layer.
3
Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
Extensor digitorum
Extensor digiti minimi
Anconeus
Lateral epicondyle
of humerus
Supraepicondylar ridge
Supraepicondylar
Lateral
epicondyle
ridge
of humerus
Lateral
epicondyle
of
humerus
Lateral
epicondyle of
of
(common
humerus
extensor
origin)
flexion
extend
of
and
forearm
abduct
of
humerus
humerus;
posterior
Extends
and
adducts
hand attriceps
the wrist
assists
in extending
(common
extensor
border
of
ulna
hand
at
wrist
Lateral
surface
of
extends
medialjoint
four
joint
forearm
origin)
olecranon
and at
digits primarily
stabilizes
elbow
joint;
Extend
and
superior
part
of
metacarpophalangeal
may
abduct
ulnaatduring
abduct
hand
posterior
surface
of at
joints, secondarily
Extensor
pronation
the wrist join
ulna
interphalangeal
joints
expansion
of
Extensor expansions
5th digit
Lateral
surface
of medial
four of
digits
distal end
of radius
Base
of
Base
Base
of 3rd
5th
of 2nd
Base
of
3rd
metacarpal
proximal
to
styloid
Baseof
ofmetacarpal
5thmetacarpal
metacarpal
Base
2nd
metacarpal
metacarpal
process
Common origin from the supraepicondylar ridge and lateral
epicondyle of the humerus
Except for the brachioradialis and anconeus, extend as tendons
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into the hand.
Supinator
Abductor pollicis longus
Extensor pollicis brevis
Extensor pollicis longus
Extensor indicis
Except for the supinator muscle, all these deep layer muscles originate from the
posterior surfaces of the radius, ulna, and interosseous membrane and pass into
the thumb and fingers.
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6
Supinator
Extensor carpi radialis brevis
Deep branch of radial nerve
Rest
Posterior interosseous nerve
continuation of deep branch of
radial nerve
7
Radial artery
Posterior interosseous
artery
origin:
common interosseous branch of
the ulnar artery
recurrent interosseous artery
End by joining to dorsal
carpal arch of the wrist
Anterior interosseous
artery
origin:
common interosseous branch of
the ulnar artery
8
Deep branch becomes posterior interosseous nerve
after emerging from between 2 heads of supinator
Posterior interosseous nerve
passes deep to extensor pollicis longus to reach
the wrist.
9
10
11
The carpal tunnel formed
anteriorly at wrist by a deep arch formed by
carpal bones & flexor retinaculum
(transverse carpal ligament)
Flexor digitorum/superficialis
Flexor pollicis longus
Median nerve
Pass through the carpal tunnel
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The extensor tendons pass into the hand in six
compartments defined by an extensor
retinaculum:
extensor digitorum & extensor
indicis posterior surface of the wrist
extensor carpi ulnaris & extensor
digiti minimi medial side of the wrist
abductor pollicis longus &
extensor pollicis brevis
extensor carpi radialis longus &
extensor carpi radialis brevis
extensor pollicis longus
through three compartments on
the lateral surface of the wrist.
13
A triangular condensation of
deep fascia that covers the
palm and is anchored to the
skin in distal regions.
Continuous with the palmaris
longus tendon, when present;
otherwise, anchored to the
flexor retinaculum.
14
Tendons of the extensor digitorum
extensor pollicis longus muscles
expand over the proximal phalanges to
form "extensor hoods" or "dorsal
digital expansions".
Tendons of the extensor digiti minimi,
extensor indicis, extensor pollicis
brevis join these hoods.
15
Palmaris brevis
Thenar muscles
Hypothenar muscles
Adductor pollicis
Lumbrical
Abductor
digiti
minimi
Flexor
digiti
minimi
Abductor pollicis brevis
Opponens
pollicis
Flexor pollicis
brevis
Interossei
16
All of the intrinsic muscles of the hand
by deep branch of the ulnar nerve
Except
three thenar & two lateral lumbrical muscles
by median nerve
17
Superficial
Deep
palmar arch
palmar arch
18
Cephalic vein originates from
lateral side of dorsal venous network.
Basilic vein originates from
medial side of dorsal venous network.
19
Ulnar nerve medial side of the palm, medial half of the dorsum of
the hand, the 5th finger, and the medial half of the 4th finger, anterior
surfaces of the medial one and a half digits,
Median nerve thumb,index,middle fingers,lateral side of the ring
[distal parts on the dorsum of the hand]
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Radial nerve dorsolateral side
Homework:
1. Which structures pass through the carpal tunnel and their anatomical relationships with each
other in the tunnel?
2. The incidence of carpal tunnel syndrome in the world and/or in Turkey?
3. The risk factors, higher in whom? Any gender disperancies in its incidence?
Please send answers to yeditepeanatomy@yahoo.com
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