Slideshow: Forearm Extensors The Funky Professor videos can be viewed here: http://publishing.rcseng.ac.uk/journal/video?videoTaxonomy=FUNK

1. Extensors of the forearm

2. The forearm is the region of the
upper limb between the elbow joint
proximally and wrist joint distally
Forearm Extensors

3. The forearm is the region of the
upper limb between the elbow joint
proximally and wrist joint distally
Elbow Joint
Forearm Extensors

4. The forearm is the region of the
upper limb between the elbow joint
proximally and wrist joint distally
Elbow JointWrist Joint
Forearm Extensors

5. The forearm is the region of the
upper limb between the elbow joint
proximally and wrist joint distally
Elbow JointWrist Joint
Forearm
Forearm Extensors

6. There are two long bones in the forearm
Forearm Extensors

7. There are two long bones in the forearm
Radius lies Laterally
Forearm Extensors

8. There are two long bones in the forearm
Radius
Ulna lies Medially
Forearm Extensors

9. The forearm is divided into 2 compartments by the
Interosseous membrane and the Deep Fascia
Interosseous membrane
Forearm Extensors

10. The forearm is divided into 2 compartments by the
Interosseous membrane and the Deep Fascia
Anterior Compartment or Flexor Compartment contain;
• Superficial Flexors
• Deep Flexors
Forearm Extensors

11. The forearm is divided into 4 compartments by the
Interosseous membrane and the Deep Fascia
Anterior Compartment or Flexor Compartment contain;
• Superficial Flexors
• Deep Flexors
Posterior Compartment or Extensor Compartment contain;
• Extensors
• Mobile Wad of Three
Forearm Extensors

12. There are 2 groups of extensors;
• Superficial Extensor Compartment
• Deep Extensor compartment
Forearm Extensors

13. There are
• 7 muscles in the superficial group
• 5 muscles in the deep group
Forearm Extensors

14. Superficial Extensors
Forearm Extensors

15. Superficial Extensors
1.Brachioradialis
Forearm Extensors

16. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
Forearm Extensors

17. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
Forearm Extensors

18. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
Collectively these muscles are
also called
‘The Mobile Wad of Three’
Forearm Extensors

19. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
4.Extensor Digitorum
Forearm Extensors

20. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
4.Extensor Digitorum
5.Extensor Digiti Minimi
Forearm Extensors

21. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
4.Extensor Digitorum
5.Extensor Digiti Minimi
1.Extensor Carpi Ulnaris
Forearm Extensors

22. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
4.Extensor Digitorum
5.Extensor Digiti Minimi
1.Extensor Carpi Ulnaris
1.Anconeus
Forearm Extensors

23. Superficial Extensors
1.Brachioradialis
2.Extensor Carpi Radialis Longus
3.Extensor Carpi Radialis Brevis
4.Extensor Digitorum
5.Extensor Digiti Minimi
1.Extensor Carpi Ulnaris
1.Anconeus
Forearm Extensors

24. Deep Extensors
1.Abductor Pollicis Longus
Forearm Extensors

25. Deep Extensors
1.Abductor Pollicis Longus
2.Extensor Pollicis Longus
Forearm Extensors

26. Deep Extensors
1.Abductor Pollicis Longus
2.Extensor Pollicis Longus
3.Extensor Pollicis Brevis
Forearm Extensors

27. Deep Extensors
1.Abductor Pollicis Longus
2.Extensor Pollicis Longus
3.Extensor Pollicis Brevis
4.Extensor Indicis
Forearm Extensors

28. Deep Extensors
1.Abductor Pollicis Longus
2.Extensor Pollicis Longus
3.Extensor Pollicis Brevis
4.Extensor Indicis
5.Supinator
Forearm Extensors

29. Tendons at the wrist

30. 1
2
345
6
RadiusUlna
There are 6 compartments on
the dorsal aspect of the wrist
Forearm Extensors

31. First Compartment
1. Abductor Pollicis Longus
2. Extensor Pollicis Brevis
1
RadiusUlna
RadiusUlna
Forearm Extensors

32. Second Compartment
1. Extensor Carpi Radialis Longus
2. Extensor Carpi Radialis Brevis
RadiusUlna
2
Forearm Extensors

33. Third Compartment
Extensor Pollicis Longus
RadiusUlna
3
Forearm Extensors

34. Fourth Compartment
1. Extensor Indicis
2. Extensor Digitorum
RadiusUlna
4
Forearm Extensors

35. Fifth Compartment
Extensor Digiti Minimi
RadiusUlna
5
Forearm Extensors

36. Sixth Compartment
Extensor Carpi Ulnaris
RadiusUlna
6
Forearm Extensors

37. 1. Abductor Pollicis Longus
1. Extensor Pollicis Brevis
2. Extensor Carpi Radialis Longus
2. Extensor Carpi Radialis Brevis
3. Extensor Pollicis Longus
4. Extensor Indicis
4. Extensor Digitorum
5. Extensor Digiti Minimi
6. Extensor Carpi Ulnaris
Forearm Extensors
1
2345
6
RadiusUln
a

38. Nerves

39. Brachioradialis
Extensor Carpi Radialis Longus
Anconeus
are supplied by the
Radial Nerve
Forearm Extensors

40. All the other extensor muscles
are supplied by the
Posterior Interosseous Nerve
deep branch of the Radial Nerve
Forearm Extensors

41. Summary of Muscles

42. Posterior Forearm
Brachioradialis
Origin Proximal 2/3 of lateral
supracondylar ridge of
humerus
Insertion Lateral surface of distal end of
radius (base of styloid process)
Action Flexes forearm
Nerve Supply Radial nerve (C5, C6 and C7)
Blood Supply Radial recurrent artery

43. Extensor Carpi Radialis
Longus
Origin Lateral supracondylar ridge of
humerus
Insertion Base of 2nd metacarpal
Action Extends and abducts hand at
wrist joint
Nerve Supply Radial nerve (C6 and C7)
Blood Supply Radial artery
Posterior Forearm

44. Posterior Forearm
Extensor Carpi Radialis
Brevis
Origin Lateral supracondylar ridge of
humerus
Insertion Base of 3rd metacarpal
Action Extends and abducts hand at
wrist joint
Nerve Supply Deep branch of radial nerve
(C7 and C8)
Blood Supply Radial artery

45. Posterior Forearm
Extensor Digitorum
Origin Common extensor origin on
lateral epicondyle of humerus
Insertion Extensor expansions of medial
four digits (not thumb)
Action Extends medial four digits at
metacarpophalangeal joints;
Extends hand at wrist joint
Nerve Supply Posterior interosseous nerve
(deep branch of radial nerve
C7, C8)
Blood Supply Interosseous recurrent and
posterior interosseous arteries

46. Posterior Forearm
Extensor Digiti Minimi
Origin Common extensor origin on
lateral epicondyle of humerus
Insertion Extensor expansion of little
finger
Action Extends 5th digit at
metacarpophalangeal and
interphalangeal joints
Nerve Supply Posterior interosseous nerve
(deep branch of radial nerve
C7, C8)
Blood Supply Interosseous recurrent artery

47. Posterior Forearm
Extensor Carpi Ulnaris
Origin Common extensor origin on
lateral epicondyle of humerus
Insertion Base of 5th metacarpal
Action Extends and adducts hand at
wrist joint
Nerve Supply Posterior interosseous nerve,
(deep branch of radial nerve
C7, C8)
Blood Supply Ulnar artery

48. Posterior Forearm
Anconeus
Origin Lateral epicondyle of humerus
Insertion Posterior olecranon process of
the ulna
Action Extends the elbow joint
Nerve Supply Radial nerve (C7, C8)
Blood Supply Posterior interosseous artery

49. Posterior Forearm
Abductor Pollicis Longus
Origin Posterior surfaces of ulna,
radius and interosseous
membrane
Insertion Base of 1st metacarpal
Action Abducts thumb, extends
thumb at carpometacarpal
joint
Nerve Supply Posterior interosseous nerve
(deep branch of radial nerve
C7, C8)
Blood Supply Posterior interosseous artery

50. Posterior Forearm
Extensor Pollicis Longus
Origin Posterior surface of middle 1/3
of ulna and interosseous
membrane
Insertion Base of distal phalanx of
thumb
Action Extends distal phalanx of
thumb at carpometacarpal and
interphalangeal joints
Nerve Supply Posterior interosseous nerve
(deep branch of radial nerve
C7, C8)
Blood Supply Posterior interosseous artery

51. Posterior Forearm
Extensor Pollicis Brevis
Origin Posterior surfaces of radius
and interosseous membrane
Insertion Base of proximal phalanx of
thumb
Action Extends proximal phalanx of
thumb at carpometacarpal
joint
Nerve Supply Posterior interosseous nerve
(deep branch of radial nerve
C7, C8)
Blood Supply Posterior interosseous artery

52. Posterior Forearm
Extensor Indicis
Origin Posterior surface of ulna and
interosseous membrane
Insertion Extensor expansion of index
finger
Action Extends 2nd digit and helps to
extend hand
Nerve Supply Posterior interosseous nerve
continuation deep branch
radial nerve (C7, C8)
Blood Supply Posterior interosseous artery

53. Posterior Forearm
Supinator
Origin Lateral epicondyle of humerus,
radial collateral and annular
ligaments, supinator fossa and
crest of ulna
Insertion Lateral, posterior and anterior
surfaces of proximal 1/3 of
radius
Action Supinates forearm
Nerve Supply Deep branch of radial nerve
(C5 and C6)
Blood Supply Recurrent interosseous artery