Second Order: Muscles of hand, fingers, and thumb Part 1

anterior, middle ulna

4 tendons run into bases of distal phalanges

flexes following joints in fingers 2 (index)-5 (little): wrist, MP, PIP, and DIP

• index and middle- Median
• ring and little- Ulnar

common flexor tendon from medial epicondyle of humerus

sides of middle phalanges of the 4 fingers (not thumb)

flexes wrist and MP, PIP joints in fingers (not thumb)

median

lateral epicondyle of humerus

extensor expansions of 4 digits and specifically into base of proximal phalanx

extend wrist and 4 fingers at MP joints; ext PIP and DIP joints

radial

tendons of flexor digitorum profundus

radial border of extensor expansions of 2-5th digits

flex MP joints, extends PIP and DIP joints of fingers (not thumb)

• 2/3- median
• 4/5- ulnar

ulnar side of 1, 2, 4, 5th metacarpals

extensor expansions of 2, 4, 5 digits and bases of proximal phalanges

adduct thumb, index, ring, and little fingers toward the axial line; assists w/ PIP and DIP joint extension

ulnar

adjacent sides of 2 metacarpals

bases of proximal phalanges extensor expansions of 2nd-4th digits

abduct 2nd-4th digits; assist with PIP and DIP joint extension

ulnar

posterior surface of proximal ulna and radius

base of 1st metacarpal (radial side)

abducts and extends CMC joint of thumb, abducts (radially deviates) and flexes wrist

radial