FOREARM AND HAND
Bronches
1 Muscular, to the flexor carpi ulnaris and the medial
half of the flexor digitorum profundus.
2 Palmar cutaneous branch arises in the middle of the
forearm and supplies the skin over the hypothenar
eminence (Fig.9.13a).
3 Dorsal cutaneous branch arises 7.5 cm above the
wrist, winds backwards and supplies the proximal
parts of the medial 2%fingers and the adjoining area
of the dorsum of the hand.
4 Articular branches are given off to the elbow joint.
5 Its branches in the palm are shown in Fig. 9.73b.
RADIAL NERVE
Course
The radial nerve divides into its two terminal branches
in the cubital fossa just below the level of the lateral
epicondyle of the humerus (Fig. 9.a).
Blonches
The deep terminalbranch (posterior interosseous) soon
enters the back of the forearm by passing through the
supinator muscle.
The superficial terminalbranch (the main continuation
of the nerve) runs dor,rrn in front of the forearm.
The superficial terminal branch of the radial nerve
is closely related to the radial artery only in the middle
one-third of the forearm (Fig. 9.10).
In the upper one-third, it is widely separated from
the artery, and in the lower one-third it passes
backwards under the tendon of the brachioradialis.
The superficial terminal branch is purely cutaneous
and is distributed to the lateral half of the dorsum of
the hand, and to the proximal parts of the dorsal
surfaces of the thumb, the index finger, and lateral half
of the middle finger.
Medial half of
flexor digitorum
profundus
Palmar
cutaneous
branch
Deep terminal
branch
Nerve passing
behind medial
intermuscular
septum
Nerve passing
behind medial
epicondyle
Flexor carpi
ulnaris
Dorsal cutaneous
branch
Flexor retinaculum
Superficial
terminal branch
Digital branches
Tendons of flexor digitorum profundus
Flexor digiti minimi
Ulnar nerve
Abductor digiti minlmi
Opponens digiti minimi
Fig. 9.13a: Course and branches of ulnar nerve
Injury to this branch results in small area of sensory
loss over the root of the thumb.
Branch to deep head of flexor pollicis brevis
Lumbricals
3rd 2nd
4th
3rd
2nd- 1 st
Dorsal interossei
Fig. 9.13b: Distribution of deep branch of ulnar nerve
Flexor pollicis brevis
Abductor pollicis brevis
Opponens pollicis
Adductor pollicis
lt
E
=o
CL
CL
f
r
Co
.E
oo
@
mebooksfree.com