5. • The skin of the anterior forearm is
supplied by fasciocutaneous
perforators; the largest is the
inferior cubital artery, which
arises from the radial artery at the
distal apex of the cubital fossa
and extends to midway down the
forearm.
6. • Fasciocutaneous perforators
from the ulnar artery supply
skin over the ulnar side of the
anterior forearm and the medial
quarter of the posterior forearm
from the cubital fossa to the
wrist.
8. MUSCLES
• The anterior compartment
contains the flexor muscles
of the forearm.
• These are arranged in
superficial and deep groups.
9.
10. SUPERFICIAL GROUP
• This group comprises five muscles.
• 1. Pronator teres.
• 2. Flexor carpi radialis.
• 3. Palmaris longus.
• 4. Flexor digitorum superficialis.
• 5. Flexor carpi ulnaris.
11.
12. PRONATOR TERES
• Origin
• It arises by two heads
(a)
superficial (humeral)
head from the medial
supracondylar ridge
and medial epicondyle
of the humerus, and
13. • (b) deep
(ulnar) head
from the
medial margin
of the coronoid
process of the
ulna.
14. • The two heads join,
proceed downwards and
laterally forming the
medial boundary of
cubital fossa, and form a
flat tendon.
15. INSERTION
• Into the rough
impression on
the middle
one-third of
the lateral
surface (most
convex part) of
the radius.
16. • Nerve supply
• By the median nerve.
• Usually before the latter passes between the
two heads of pronator teres.
17. • Actions
• It is the main pronator of the forearm. And acts as a
weak flexor of the elbow joint.
18.
19. Origin
• From the medial
epicondyle of humerus
by a common flexor
origin.
• Antebrachial fascia and
the adjacent fascial
septa.
FLEXOR CARPI RADIALIS
21. • Insertion
• On to the anterior aspects of the bases of
second and third metacarpals.
Groove on trapezium
22. Nerve supply:
Median nerve
Action:
Flexor of the wrist.
Combined actions
of flexor carpi
radialis and
extensor carpi
radialis longus and
brevis produce
abduction of the
wrist
24. • Insertion
• Its long cord-like
tendon crosses
superficial to the
flexor retinaculum
and attaches to its
distal part and joins
the apex of palmar
aponeurosis.
25. NERVE SUPPLY
• By the median
nerve.
• Actions
• It flexes the wrist
and makes the
palmar
aponeuroses
tense.
26.
27. FLEXOR CARPI ULNARIS
• The flexor carpi
ulnaris (FCU) is
most medial of
the superficial
flexors of the
forearm.
28. ORIGIN
• It arises by two heads:
a small humeral head
and a large ulnar
head.
• (a) humeral head from
the medial epicondyle
of the humerus by a
common flexor origin.
29. • (b) ulnar head
from the medial
margin of the
olecranon process
and by an
aponeurosis from
the upper two-third
of the posterior
border of the ulna.
33. • Actions
• 1. Acting with the extensor carpi ulnaris, it
adducts the wrist joint.
34. • 2. Acting with the flexor carpi radialis, it
flexes the wrist joint.
35. • The flexor
digitorum
superficialis (FDS)
is the largest
muscle of the
superficial group of
muscles on the
front of the
forearm.
FLEXOR DIGITORUM
SUPERFICIALIS
36. ORIGIN
• It arises by two heads:
• (a) humero-ulnar head,
from the medial
epicondyle of humerus,
sublime tubercle on the
medial margin of the
coronoid process of ulna
and medial (ulnar)
collateral ligament of the
elbow joint,
37. • (b) radial head,
from the anterior
oblique line of the
radius, extending
from the radial
tuberosity to the
insertion of
pronator teres
(upper half of the
anterior border of
radius).
38. INSERTION
• Middle phalanges of medial
four fingers. The mode of
insertion is:
• The muscles splits into two
layers:
• superficial and deep.
The superficial layer forms two
tendons, which are inserted into
middle phalanges of middle and
ring fingers.
39.
40.
41. • The deep layer
also forms two
tendons, which
are inserted into
middle
phalanges of
index and little
fingers.
46. NERVE SUPPLY
• By the median nerve.
• Action:
It produces flexion of the middle phalynx at the
proximal interphalyngeal
joints.
47. DEEP GROUP FLEXOR MUSCLES
• There are three in
number and consist
of flexor pollicis
longus, flexor
digitorum profundus
and pronator
quadratus
48. FLEXOR DIGITORUM PROFUNDUS
• It is the bulkiest muscle of
the forearm.
• Origin
• 1. From upper three-fourth
of the anterior and medial
surfaces of the shaft of ulna
and adjacent medial half of
the interosseous membrane.
49. • By an aponeurosis from
upper three-fourth of the
posterior border of ulna
along with flexor and
extensor carpi ulnaris
muscles.
50. The muscle forms
four tendons,
which enter the
palm by passing
deep to the flexor
retinaculum within
the carpal tunnel
51.
52. INSERTION
• Opposite the proximal
phalanx of
corresponding digit, the
tendon perforates the
tendon of flexor
digitorum superficialis
and passes forward to
be inserted in palmar
surface of the distal
phalanx.
53.
54. • Nerve supply
• 1. Medial half by the ulnar nerve.
• Lateral half by the anterior interosseous nerve –
a branch of the median nerve.
• Actions
• FDP flexes the distal interphalangeal (DIP) joints
of medial four digits. It also helps to flex the wrist
joint.
55.
56.
57. FLEXOR POLLICIS
LONGUS
• The flexor pollicis
longus lies lateral to
the FDP
• ORIGIN:
• From upper two-third of
the anterior surface of
the radius below the
anterior oblique line
and adjoining part of
the interosseous
membrane.
58. INSERTION
• Into the anterior
surface of the
base of distal
phalanx of the
thumb.
59.
60. • Nerve supply:
Anterior interosseous branch of the
median nerve.
Actions
• It primarily flexes the distal phalanx of the
thumb
61. • but secondarily it also flexes proximal phalanx and first
metacarpal at the metacarpophalangeal (MP) and
carpometacarpal (CM) joints respectively.
62.
63. PRONATOR QUADRATUS
• It is a flat quadrilateral muscle, which extends across the
front of the distal parts of the radius and ulna.
64. • Origin
From an oblique ridge on the lower one-
fourth of the anterior surface of the shaft
of ulna and medial part of this surface.
Insertion
1. The superficial fibres into the distal
one-fourth of the anterior border and
anterior surface of the shaft of radius.
2. The deeper fibres into the triangular
area above the ulnar notch of the
radius.
65. • Nerve supply
By anterior interosseous nerve.
• Actions
Pronator quadratus is the chief
pronator of the forearm and is
assisted by pronator teres only in
rapid and forceful pronation.
66. • It is a fascial lined
potential space
deep to the long
flexor tendons of
the forearm, where
the proximal parts
of the synovial
sheath of the
flexor tendons of
the hand extend
SPACES OF PARONA
68. APPLIED ASPECTS
• Accumulation of pus from infected synovial
sheaths of flexor tendons may extend into
space of parona.
• The pus is drained by incisions along the
borders of the forearm, which are not
crossed by the motor nerves and act as
INTERNERVOUS LINES
69. BLOOD VESSELS OF THE FRONT OF
FOREARM
• The arteries of the front of the forearm are ulnar and
radial arteries. They mainly supply blood to the
hand through superficial and deep palmar arterial
arches. The blood supply to the forearm is mainly
derived from the anterior and posterior interosseous
arteries branches of common interosseous artery,
the terminal branches of the common interosseous
artery, a branch of the ulnar artery.
70. RADIAL ARTERY
• Origin and Course
The radial artery is the smaller terminal
branch of the brachial artery. It begins in
cubital fossa at the level of the neck of
radius. It passes downwards to the wrist
with lateral convexity.
71. • In the upper part, it
lies beneath the
brachioradialis on
the deep muscles of
the forearm, begins
in the cubital fossa
1cm below the bend
of elbow at the level
of neck of radius,
73. COURSE
• The course is divided into 3 parts.
• In the forearm
• At the wrist
• In the hand.
74.
75. • It extends downwards
with a lateral
convexity from its
origin to the front of
styloid process at the
distal end of radius,
where the pulsation of
artery is usually felt.
76. • The artery leaves the apex
of cubital fossa, where it is
partially overlapped by
brachioradialis. In the rest
of the course it runs sub-
fascially and intervenes
between the tendons of
brachioradialis and flexor
carpi radialis.
BR
FCR
77. • It winds dorsally
beneath the
tendons of
abductor pollicis
longus and
extensor pollicis
brevis, crosses the
anatomical snuff
box
APL
EPB
78. • and leaves the
dorsal surface of the
wrist through a
triangular gap
between the two
heads of first dorsal
interosseous
muscle, where the
artery is crosses
superficially by the
extensor pollicis
longus tendon
EPL
79. RELATIONS
• Anterior:
The upper part of the
radial artery is overlapped
by brachioradialis, while
its lower part is covered
only by the skin, and
superficial and deep
fasciae.
80. POSTERIOR:
• The radial artery from above to
downward lies
on the following structures:
(a) Biceps tendon.
(b) Supinator.
(c) Pronator teres.
(d) Flexor digitorum superficialis.
These structures together form
the bed of the radial artery.
82. • Branches in the Forearm
1. Muscular branches to the lateral
muscles of the forearm.
2. Radial recurrent artery arises in the
cubital fossa and takes part in the formation
of arterial anastomose around the elbow
joint.
83.
84. • 3. Palmar carpal branch, arises near the wrist
and anastomosis with the palmar carpal branch of
the ulnar artery.
4. Superficial palmar branch arises just above the
wrist and enters the palm of the hand by passing in
front of the flexor retinaculum. It joins the terminal
part of the ulnar artery to complete the superficial
palmar arch.
85.
86. ULNAR ARTERY
• Course
The ulnar artery is the larger terminal
branch of the brachial artery. It begins in
the cubital fossa at the level of the neck
of the radius (or 1 cm distal to the
flexion crease of the elbow).
87.
88. • It runs downwards and
reaches the medial side
of the forearm midway
between the elbow and
wrist In the upper one-
third of forearm, the
course is oblique (I .e.,
downwards and medially)
but in lower two-third it is
vertical.
89. • The median nerve
lies medial to the
artery 2.5 cm distal
to the elbow and
then crosses the
artery.
90. • The ulnar nerve lies
medial to the distal
two-third of the artery.
It enters the palm by
passing in front of
flexor retinaculum
lateral to the ulnar
nerve and the
pisiform bone.
91. • It terminates in the hand by dividing into
large superficial and small deep
branches. The superficial branch—the
continuation of the artery superficial
palmar arch, which anastomosis with
superficial palmar branch of the radial
artery.
92.
93. RELATIONS
• In the upper part of its
course, it lies deep to
superficial flexor muscles. In
the lower part of its course, it
becomes superficial and lies
between the tendons of flexor
carpi ulnaris and flexor
digitorum superficialis.
94. • Anterior: The upper part of the ulnar artery is covered by five
superficial muscles of the forearm, viz.
(a) Pronator teres.
(b) Flexor carpi radialis.
(c) Palmaris longus.
(d) Flexor digitorum superficialis.
(e) Flexor carpi ulnaris.
The lower part of the ulnar artery is covered only
by the skin and superficial and deep fasciae.
95.
96. • Posterior:
Only the origin of
ulnar artery lies on
brachialis, while in the
remaining whole part of
its course it lies on
flexor digitorum
profundus.
98. BRANCHES
Branches
• 1. Muscular branches
to neighboring muscles.
• 2. Anterior and
posterior ulnar
collateral (recurrent)
arteries, which take part
in the arterial
anastomosis around the
elbow joint.
99. • 3. Common interosseous artery,
which arises from the upper part of
the ulnar artery and after a very
short course at the upper border of
interosseous membrane, it divides
into anterior and posterior
interosseous arteries.
100.
101. • Anterior and
posterior ulnar
carpal branches,
which take part in
the formation of
anterior and
posterior carpal
arches.
102. • 5. Terminal
branches are two,
the larger
superficial branch
continues as the
superficial palmar
arch, while the
smaller deep
branch joins the
deep palmar arch.
