EXTRINSIC MUSCLES OF THE FINGER JOINTS

Question 1

FLEXOR DIGITORUM SUPERFICIALIS: O,I

Answer 1

O: medial epicondyle of the humerus via CFT and coronoid process of ulna (HU head); proximal 1/2 of anterior shaft of the radius (radial head)

I: anterior surface of the middle phalanx of fingers 2-5

Question 2

FLEXOR DIGITORUM SUPERFICIALIS: A,N

Answer 2

A: flexes fingers 2-5 at the MCP and PIP joints and the hand at the wrist joints

N: median n.

Question 3

FLEXOR DIGITORUM PROFUNDUS: O,I

Answer 3

O: proximal 1/2 of the medial and anterior ulna and IOM

I: anterior surface of the distal phalanges of fingers 2-5

Question 4

FLEXOR DIGITORUM PROFUNDUS: A,N

Answer 4

A: flexes fingers 2-5 at the MCP, PIP and DIP joints; flexes the hand at the wrist joint

N: median and ulnar n.

Question 5

FLEXOR POLLICIS LONGUS: O,I

Answer 5

O: anterior surface of the radius, IOM, medial epicondyle of the humerus and the coronoid process of the ulna

I: anterior aspect of the base of the distal phalanx of the thumb

Question 6

FLEXOR POLLICIS LONGUS: A,N

Answer 6

A: flexes the thumb at the CMC, MCP and IP joints; flexes the hand at the wrist joint

N: median n.

Question 7

EXTENSOR DIGITORUM: O, I

Answer 7

O: lateral epicondyle of the humerus at the CET

I: via the DDE onto the posterior surface of the middle and distal phalanges of fingers 2-5

Question 8

EXTENSOR DIGITORUM: A,N

Answer 8

A: extends fingers 2-5 atht eh MCP, PIP and DIP; extends the hand at the wrist joint

N: radial n.

Question 9

EXTENSOR DIGITI MINIMI: O,I

Answer 9

O: lateral epicondyle of the humerus via the CET

I: via the DDE onto the posterior surface of the middle and distal phalanges of the 5th finger through the ulnar side of the ED mm.

Question 10

EXTENSOR DIGITI MINIMI: A,N

Answer 10

A: extends finger 5 at the MCP, PIP and DIP; extends the hand at the wrist joint

N: radial n.

Question 11

ABDUCTOR POLLICIS LONGUS: O,I

Answer 11

O: middle 1/3 of posterior radius, ulna and IOM

I: lateral side of the base of the first MC

Question 12

ABDUCTOR POLLICIS LONGUS: A,N

Answer 12

A: ABD and EXT the thumb at the CMC joint

N: radial n.

Question 13

EXTENSOR POLLICIS BREVIS: O,I

Answer 13

O: distal 1/3 of the posterior radius and the adjacent IOM

I: posterolateral base of the prox phalanx of the thumb

Question 14

EXTENSOR POLLICIS BREVIS: A,N

Answer 14

A: extends and ABD thumb at the CMC joint; extends thumb at MCP joint

N: radial n.

Question 15

EXTENSOR POLLICIS LONGUS: O,I

Answer 15

O: middle 1/3 of posterior ulna and adjacent IOM

I: via DDE onto posterior surface of distal phalanx of thumb

Question 16

EXTENSOR POLLICIS LONGUS: A,N

Answer 16

A: extends the thumb at the CMC, MCP and IP joints

N: radial n.

Question 17

EXTENSOR INDICIS: O,I

Answer 17

O: distal 1/3 of the posterior ulna and IOM

I: via DDE onto posterior surface of middle and distal phalanges of the index finger through the ulnar side of the tendon of the ED mm.

Question 18

EXTENSOR INDICIS: A,N

Answer 18

A: extends index finger at MCP, PIP and DIP; extends hand at wrist joint

N: radial n.