anatomy lab IV: Forearm II, Elbow, Wrist, Hand

what is the common flexor origin?

the medial epicondyle is the common flexor origin

the anterior compartment of the forearm is innervated by what nerve?

median nerve

what muscles does the ulnar nerve innervate?

Flexor carpi radialis and medial half of flexor digitorum profundus are innvervated by the ulnar nerve

what 4 muscles are part of the superficial layer of the anterior compartment of the forearm?

protonator teres, flexor carpi radialis, palmaris longus, and flexor carpi ulnaris

what is the 2nd tagged (from left to right) area? Then state the origin, insertion, and main actions

• protonator teres

• origin: medial epicondyle of humerus, coronoid process of the ulna

• insertion: lateral side of middle of radius

• main actions: protonation of forearm, flexion of forearm

(diagonal to radius, dividing line of posterior and anterior side)

what is the 3rd tagged (from left to right) area? Then state the origin, insertion, and main actions

• flexor carpi radialis

• origin: medial epicondyle of humerus

• insertion: 2nd metacarpal

• main actions: flexion of hand, ABduction of hand

(thick muscle)

what is the 4th tagged (from left to right) area? Then state the origin, insertion, and main actions.

• palmaris longus

• origin: medial epicondyle of humerus

• insertion: palmar aponeurosis (sheet of skin)

• main actions: flexion of hand, tightening of flexor aponeurosis

what is the 5th tagged (from left to right) area? Then state the origin, insertion, and main actions.

• flexor carpi ulnaris

• origin: medial epicondyle of humerus

• insertion: pisiform, hamate, 5th metacarpal

• main action: flexion of hand, ADduction of hand

(big & thick; most medial)

what is the 2nd tagged (from left to right) area? Then state the origin, insertion, and main actions.

• flexor digitorum superficialis (huge bundle of tendons in the middle)

• origin: medial epicondyle of humerus

• insertion: middle phalanx of digits 2-5 (separate flexor for digit 1)

• main actions: flexion of PIP joints, flexion of MCP joints, flexion of wrist

what is the 1st tagged (from left to right) area? Then state the origin, insertion, and main actions.

• flexor digitorum profundus (thick, lighter in color, DIP; beneath flexor digitorum superficilias)

• origin: anterior ulna, interosseous membrane

• insertion: distal phalanx of digits 2-5

• main actions: flexion of DIP and PIP joints, flexion of MCP joints, flexion of wrist

what is the 2nd tagged (from left to right) area? Then state the origin, insertion, and main actions.

• flexor pollicis longus (lateral to flexor digitorum profundus; lighter in color)

• origin: radius, interosseous membrane

• insertion: distal phalanx of digit 1

• main actions: flexion of distal phalanx of digit 1

what is the tagged area? Then state the origin, insertion, and main actions.

• pronator quadratus (most deep; box; striations)

• origin: distal ulna

• insertion: distal radius

• main actions: protonation of forearm

there is a sheet of muscle that goes over the carpals and tendons. What is this called?

flexor retinaculum (transverse carpal ligament)

how many tendons pass the flexor retinaculum?

8 tendons (4FDS, 4FDP, 1 FPL)

compression of the medial nerve under flexor retina

carpal tunnel syndrome