FLEXOR COMPARTMENT of forearm

1. FLEXOR COMPARTMENT OF
FOREARM
Dr N. Anuradha
MAMS

2. Forearm
Extent - elbow to the wrist
Contains two bones the radius and
ulna joined by an interosseous
membrane

3. Fascial Compartments of Forearm
• Superficial fascia – thin and
has minimal fat
• Antebrachial fascia (deep
fascia)
– does not form a thick sleeve
as in the thigh
– permits frequent movements
of muscles of forearm without
impeding the movements
4

4. Fascial Compartments of Forearm
• Antebrachial fascia (deep fascia)
– Attached to the posterior
subcutaneous border of ulna
• Thickened to form
Flexor retinaculum
Extensor retinaculum.
• Lateral intermuscular septum –
extends from deep fascia to the
radius
5
Compartment of forearm
Anterior and posterior

5. Contents
• MUSCLES – 8 - arranged in 2 groups
Superficial - 5
Deep - 3
• ARTERIES – 2 - radial & ulnar,( anterior
interosseous)
• NERVES – 3 - median, ulnar &radial

6. Muscles
• Superficial -5
1. Pronator teres
2. Flexor carpi radialis
3. Palmaris longus
4.Flexor carpi ulnaris
5.Flexor digitorum superficialis

8. Pronator teres
ORIGIN:
Humeral-medial supracondylar ridge
Ulnar-medial border of coronoid process
INSERTION:
Middle of lat.surface of radius
NERVE SUPPLY:
Median nerve
ACTION:
Pronation

9. ORIGIN
NERVE SUPPLY

10. 2)Flexor carpi radialis
ORIGIN:
Medial epicondyle
INSERTION
Base of 2nd &3rd metecarpals
NERVE SUPPLY:
Median
ACTION:
Flexion

11. 3)Palmaris longus
ORIGIN:
Medial epicondyle
INSERTION:
Central part of palmar aponeurosis
NERVE SUPPLY
Median
ACTION:
Weak flexor

12. 4)Flexor carpi ulnaris
ORIGIN:
Humeral-medial epicondyle
Ulnar-medial margin of olecranon
INSERTION:
Pisiform bone
NERVE SUPPLY:
Ulnar
ACTION:
Flexion

13. ORIGIN:
Humero-ulnar head-
Medial epicondyle
Radial-ant.oblique line
INSERTION:
Sides of middle phalanx
NERVE SUPPLY:
Medain nerve
ACTION:
Flexion of middle phalanx
Flexor digitorum superficialis:
(Sublimis)

16. Deep - 3
1. Flexor pollicis longus
2. Flexor digitorum profundus
3. Pronator quadratus

17. ORIGIN:
• Ant. Surface of radius
• Interosseous membrane
INSERTION
Base of distal phalanx of
thumb
• NERVE SUPPLY
anterior interosseous n.
• ACTION
Flexor of thumb
1)Flexor pollicis longus

18. 2)Flexor digitorum profundus
ORIGIN:
• Ant&medial surface of ulna
• Interosseous membrane
INSERTION:
Base of terminal phalanx of
Little finger.
NERVE SUPPLY:
medial – ulnar
Lateral - AIN
ACTION:
Flexes terminal phalanges

20. • ORIGIN
• INSERTION
• NERVE SUPPLY
• ACTION
3)Pronator Quadratus

21. Pronator Quadratus
Origin
• Oblique ridge on the lower one-fourth of
anterior surface of shaft of ulna and area
medial to it.
Direction of fibers
• Fibers runs laterally (horizontal).Unique feature
Insertion
• Superficial fibers: Distal one-fourth of anterior
surface and anterior border of radius.
• Deep fibers: Triangular area above the ulnar
notch of radius
Human Anatomy/Yogesh Sontakke 22

22. Pronator Quadratus
InnervationNeet
• Anterior interosseous branch of median nerve
Actions
• Superficial fibers – pronation of forearm.
Clinical testing
• Ask to pronate the forearm against the
resistance.
• Pronator quadratus is chief pronator of
forearm and its action is assisted by pronator
teres muscle
Human Anatomy/Yogesh Sontakke 23

23. Space of parona:
Fascial lined potential space deep to flexor tendons
Boundaries:
In front: FDP &FPL
Behind: PQ & interosseous membrane
Above: FDS
On each side: borders of forearm

24. ARTERIES OF FRONT
OF FOREARM
1. Ulnar artery
2. Anterior interosseous artery
3. Radial artery
Human Anatomy/Yogesh Sontakke 26

25. Blood vessels of front of forearm:
1)Radial artery:
• Terminal branch of brachial artery
• Runs b/w BR&FCR
• Crosses anatomical snuff box
Branches:
1. Radial recurrent
2. Muscular
3. Palmar carpal
4. Dorsal carpal
5. Superficial palmar
6. First dorsal metacarpal
7. Princeps pollicis
8. Radialis indicis

26. Radial artery course in forearm

28. Branches
1. Muscular branches
2. Radial recurrent carpal branch
3. Anterior (palmar) carpal branch
4. Posterior (dorsal) carpal branch
5. Superficial palmar branch –
completes superficial palmar arch
Human Anatomy/Yogesh Sontakke 30

29. Clinical Integration
Radial pulse
• In clinical examination, radial artery
is commonly palpated to measure
pulse rate
• Site: in the lower part of forearm
against the anterior surface of lower
end of radius lateral to the tendon of
flexor carpi radialis.Viva,
Practical guide
Human Anatomy/Yogesh Sontakke 31

30. Ulnar artery:
• Deeply placed
• Runs b/w FCU&FDS
• Crosses Flexor retinaculum
• Divides into superficial & deep
Branches:
1. Anterior ulnar recurrent
2. Posterior ulnar recurrent
3. Common interosseous
4. Palmar & dorsal carpal branches
5. Muscular

31. Ulnar artery course in the forearm

32. Human Anatomy/Yogesh Sontakke 34

33. Anterior Interosseous Artery
• Terminal branch of common
interosseous artery.Neet
• Also called volar
interosseous artery.
• Descends on the anterior
surface of interosseous
membrane with anterior
interosseous nerve.Identification
feature, MCQ
Human Anatomy/Yogesh Sontakke 35

34. Anterior Interosseous Artery
Branches
1. Muscular branches
2. Nutrient arteries to radius
and ulna
3. Median artery (only 8%
people) that runs with median
nerve.MCQ
Human Anatomy/Yogesh Sontakke 36

35. Nerves of flexor copm,. forearm
• 1 radial artery
• 2 ulnar artery.
1 . MEDIAN NERVE
2. Ulnar NERVE

36. Nerves:
Median nerve:
 Lies b/w 2 heads of pronator teres
Branches:
1. Muscular
2. Anterior interosseous
3. Articular
4. Palmar cutaneous
5. Communicating

37. Median nerve in forearm

38. Human Anatomy/Yogesh Sontakke 40

39. Ulnar nerve:
 Lies b/w FCU
 Accompanies ulnar artery
Branches:
1. Muscular
2. Articular
3. Dorsal branch
4. Palmar cutaneous

40. Ulnar Nerve
• Branch of medial cord of
brachial plexus
• Root value: C7, C8, and
T1.Neet
Human Anatomy/Yogesh Sontakke 42

41. Ulnar nerve in forearm

42. Ulnar nerve in forearm

43. Ulnar nerve

44. Radial nerve:
• Divides into superficial & deep
• Deep br. In post. Compartment
• Superficial br. Rest on supinator,
pronator teres, FDS& FPL

45. Volkmann’s ischemic contracture
 Sudden complete occlusion of brachial artery
 Cause paralysis of flexor muscles of forearm due to
ischemia
 Undergo necrosis and fibrous tissue replaces the
necrotic tissue.

46. Muscles shorten permanently producing a
• Flexor deformity characterized by flexion of the wrist,
• extension of the MP joints
• Flexion of the IP joints,
• Leads to loss of hand power.

47. THANK YOU