Lecture Exam 2 - Posterior Forearm Compartment and Intrinsic Hand Muscles

Brachioradialis

Extensor Carpi Ulnaris, Extensor Digiti Minimi, Extensor Digitorum, Extensor Carpi Radialis Brevis, Extensor Carpi Radialis Longus

1st layer of Posterior Forearm

Extensor Carpi Radialis Longus

Extensor Carpi Radialis Brevis

Humerus

Origin of Brachioradialis

proximal to the Styloid Process of the Radius

Insertion of Brachioradialis

Flexes forearm at elbow

Action of Brachioradialis

Radial nerve

Nerve of Brachioradialis

Extensor Digitorum

Extensor Digiti Minimi

Extensor Carpi Ulnaris

Lateral Epicondyle of Humerus

Origin of Extensor Carpi Ulnaris

Posterior side of Base of 5th Metacarpal

Insertion of Extensor Carpi Ulnaris

Wrist extension

Action of Extensor Carpi Ulnaris

proximal to the Lateral Epicondyle of Humerus

Origin of Extensor Carpi Radialis Longus

Posterior side of Base of 2nd Metacarpal

Insertion of Extensor Carpi Radialis Longus

Wrist extension

Action of Extensor Carpi Radialis Longus

Radial Nerve

Nerve of Extensor Carpi Radialis Longus

Lateral Epicondyle of Humerus

Origin of Extensor Carpi Radialis Brevis

Posterior side of Base of 3rd Metacarpal

Insertion of Extensor Carpi Radialis Brevis

Wrist extension

Action of Extensor Carpi Radialis Brevis

Deep Branch of the Radial Nerve

Nerves for most of 1st layer posterior forearm

Mallet Finger

Avulsion of Extensor Tendon from Distal Phalanx, resulting in fixed flexion

Extensor Pollicis Longus, Extensor Indicis, Abductor Pollicis Longus, Extensor Pollicis Brevis, Supinator

Layer 2 of posterior forearm

Supinator

Abductor Pollicis Longus

Extensor Pollicis Brevis

Extensor Pollicis Longus

Extensor Indicis

Lateral Epicondyle of Humerus

Origin of Supinator

Radius

Insertion of Supinator

Supination of the Forearm

Action of Supinator

Deep Branch of Radial Nerve

Nerve of Supinator

Posterior side of Distal Phalanx of Digit 1

Insertion of Extensor Pollicis Longus

Thumb extension

Action of Extensor Pollicis Longus

Extensor expansion of Digit 2

Insertion of Extensor Indicis

Extends index finger

Action of Extensor Indicis

Lateral aspect of Base of the 1st Metacarpal

Insertion of Abductor Pollicis Longus

Thumb abduction

Action of Abductor Pollicis Longus

Posterior side of Proximal Phalanx of Digit 1

Insertion of Extensor Pollicis Brevis

Thumb extension

Action of Extensor Pollicis Brevis

Extensor Pollicis Longus

Tendon that hooks on Lister's Tubercle

Posterior Interosseous Nerve

Nerve of most of Posterior Compartment of the Forearm Layer 2

Anatomical Snuffbox

Located between Extensor Pollicis Brevis and Extensor Pollicis Longus Tendons

Anatomical Snuffbox

Pulse point for Radial Artery

De Quervain Tenosynovitis

Repetitive use injury resulting in inflammation of APL and EPB tendons passing through same tendinous sheath; presents pain over Radial Styloid Process

Lumbrical

Flexor Digitorum Profundus Tendons

Origin of Lumbrical Muscles

Extensor Expansions

Insertion of Lumbrical Muscles

Median Nerve

Nerve of Lumbrical Muscles 1 and 2 (Lateral)

Flex Digits 2-5 at Metacarpophalangeal Joints; Extend Digits 2-5 at the Proximal and Distal Interphalangeal Joints

Action of Lumbrical Muscles

Z position

Normal Lumbrical Function

Dorsal Interosseous

Palmar Interosseous

Abduction of Digits 2 and 4

Action of Dorsal Interosseous

Adduction of Digits 2, 4, and 5

Action of Palmar Interosseous

T1

Myotome of Interosseous Muscles

Palmaris Brevis

medial skin of hand

Origin of Palmaris Brevis

Deepens concavity of palm to augment grip

Action of Palmaris Brevis

Superficial Branch of Ulnar Nerve

Nerve of Palmaris Brevis

Abductor Pollicis Brevis

Adductor Pollicis

Flexor Pollicis Brevis

Opponens Pollicis

Abductor Digiti Minimi

Flexor Digiti Minimi Brevis

Opponens Digiti minimi

Tubercles of the Scaphoid and Trapezium Bones

Origin of Abductor Pollicis Brevis

lateral side of Proximal Phalanx of thumb

Insertion of Abductor Pollicis Brevis

Thumb abduction

Action of Abductor Pollicis Brevis

Tubercles of the Scaphoid and Trapezium Bones

Origin of Flexor Pollicis Brevis

lateral side of Proximal Phalanx of thumb

Insertion of Flexor Pollicis Brevis

Thumb flexion

Action of Flexor Pollicis Brevis

Tubercles of the Scaphoid and Trapezium Bones

Origin of Opponens Pollicis

lateral side of 1st Metacarpal

Insertion of Opponens Pollicis

Medial Rotation of 1st Metacarpal

Action of Opponens Pollicis

Recurrent Branch of the Median Nerve

Nerve of the Thenar Compartment Muscles

Deep Branch of the Ulnar Nerve

Nerves for most of Intrinsic hand muscles

2nd and 3rd Metacarpals, Capitate Bone

Origin of Adductor Pollicis

medial side of Proximal Phalanx of thumb

Insertion of Adductor Pollicis

Thumb adduction

Action of Adductor Pollicis

Pisiform

Origin of Abductor Digiti Minimi

Medial side of Proximal Phalanx of digit 5

Insertion of Abductor Digiti Minimi

Abduction of digit 5

Action of Abductor Digiti Minimi

Hook of Hamate Bone

Origin of Flexor Digiti Minimi Brevis

Medial side of Proximal Phalanx of digit 5

Insertion of Flexor Digiti Minimi Brevis

Flexion of digit 5

Action of Flexor Digiti Minimi Brevis

Hook of Hamate Bone

Origin of Opponens Digiti Minimi

medial side of 5th Metacarpal

Insertion of Opponens Digiti Minimi

Lateral Rotation of 5th Metacarpal

Action of Opponens Digiti Minimi

Superficial & Deep Palmar Arch

C6

Dermatome of Digit 1

C7

Dermatome of Digits 2-3

C8

Dermatome of Digits 4-5

Median Nerve

Nerves for Blue area

Ulnar Nerve

Nerves for green area

Radial nerve

Nerves for orange area