Antebrachium Anterior Compartment

Question 1

Pronator Teres

Answer 1

Superficial Layer
O: Ulnar head = coronoid process
Humeral head = medial epicondyle
I: Middle convexity of lateral surface of radius
Action: Pronates and flexes forarm
INNE: Median n. (C6, C7)

Question 2

Flexor Carpi Radialis

Answer 2

Superficial Layer
O: medial epicondyle
I: Base of 2nd Metacarpal
Action: FLX and ABD of hand at wrist
INNE: Median n. (C6, C7)

Question 3

Flexor Carpi Ulnaris

Answer 3

Superficial Layer
O: Humeral Head = Medial epicondyle
Ulnar head = olecranon and posterior ulna via aponeurosis
I: pisiform, hook of hamate, 5th Metacarpal
Action: FLX and ADD hand at wrist
INNE: Ulnar n. (C7, C8)

Question 4

Palmaris Longus

Answer 4

Superficial Layer
O: Medial epicondyle
I: distal half of retinaculum and apex of palmar aponeurosis
Action: FLX wrist and tenses palmar aponeurosis
INNE: Median n. C7, C8

Question 5

Flexor Digitorum Superficialis

Answer 5

Intermediate layer
O: Humeroulnar head = Medial epicondyle (common flexor origin and coronoid process)
Radial head = superior half of anterior
I: shafts of middle phalanges of medial four digits
Action: FLX middle phalanges at proximal IP joints of middle four digits; more strongly, it FLX proximal phalanges at MCP joints
INNE: Median n. (C7-T1)

Question 6

Flexor Digitorum Profundus

Answer 6

Deep Layer
O: proximal three quarters of medial and anterior surfaces of ulna and interosseous membrane
I: Medial head; Bases of distal phalanges of 4th and 5th digits
Lateral head; Bases of distal phalanges of 2nd and 3rd digits
Action: Medial H = FLX distal phalanges 4 and 5 at distal IP joints
Lateral H = FLX distal phalanges 2 and 3 at distal IP joints
INNE: Medial H = Ulnar n. (C8, T1)
Lateral H = Anterior interosseous (C8, T1)

Question 7

Pronator Quadratus

Answer 7

Deep Layer
O: Distal quarter of anterior surface
I: Distal quarter of anterior surface of radius
Action: Pronates the antebrachium; deep fibers bind to radius and ulna together
INNE: Anterior Interosseous n. from median n. (C8, T1)

Question 8

Flexor Pollicis Longus

Answer 8

Deep Layer
O: Anterior surface of radius and adjacent interosseous membrane
I: Base of distal phalanx of thumb
Action: FLX phalanges of first digit (thumb)
INNE: Anterior Interosseous n., from the Median n. (C8-T1)