Anatomy: Palm of Hand

Question 1

Branches of Ulnar Artery

Answer 1

Anterior/Posterior Recurrent, common interosseus and muscular

Question 2

Common interosseus Artery

Answer 2

Off of ulnar artery below radial tuberosity

Question 3

Posterior interosseous

Answer 3

passes posteriorly to supply extensor compartment

Question 4

Anterior interosseous

Answer 4

anterior side, down to wrist - then passes posteriorly to anastomose w/ p.i.

Question 5

metacarpals

Answer 5

5

Question 6

carpals

Answer 6

8

Question 7

phalanges

Answer 7

14 (3 for all but thumb)

Question 8

Boxer’s fracture

Answer 8

Fracture of the 5th metacarpal, often referred to as a boxer’s fracture, occurs when an unskilled person punches someone with a closed and abducted fist. The head of the bone rotates over the distal end of the shaft, producing a flexion deformity.

Question 9

Common site of cyst in hand

Answer 9

Cystic swelling associated w/ tendon and commonly connected to tendons synovial sheath - Distal attachment of ECRB tendon into 3rd metacarpal bone common

Question 10

What ligament forms the carpal tunnel?

Answer 10

Flexor retinaculum (transverse carpal ligament)

Question 11

What nerve is involved in carpal tunnel syndrome?

Answer 11

Median nerve

Question 12

What are the clinical manifestations of carpal tunnel syndrome?

Answer 12

Odd sensations in lateral 3.5 digits, loss of thenar muscle function (recurrent branch of median nerve)

Question 13

Why is there loss of flexion of the proximal interphalangeal (PIP) joints of all the digits with severance of the median nerve in the proximal forearm or arm?

Answer 13

Median nerve innervates → flexor digitorum superficialis which flexes the PIP (for all digits)

Question 14

Why is there loss of flexion of only the distal interphalangeal (DIP) joints of the index and middle fingers and not the ring and little fingers with severance of the median nerve?

Answer 14

DIP of 4th and 5th flexed by ulnar half of FDP, ulnar half innervated by ulnar nerve

Question 15

Why is flexion of the metacarpophalangeal (MP) joints and extension of the interphalangeal (IP) joints of the index and middle fingers affected by injuries of the median nerve in the elbow region?

Answer 15

FDS, FDP and also the 1st and 2nd lumbricals innervated by median nerve

Question 16

Which hand muscles are innervated by the median and ulnar nerves?

Answer 16

Median - thenar muscles (3) and 1st/2nd lumbricals

Ulnar - hypothenar muscles, 3rd/4th lumbricals, palmar and dorsal interossei, adductor pollicis

Question 17

Lumbricals

Answer 17

Flex digits at MP joints, extend interphalangeal joints

ulnar
median nerves

Question 18

Felon

Answer 18

pulp-space infection

Infection of pulp (pad) of terminal phalanx

Question 19

What thumb ligament is involved in skier’s (game-keeper’s) thumb, and how does it occur?

Answer 19

Ulnar collateral ligament of 1st MP following hyperabduction of the thumb

Question 20

“Cubital tunnel syndrome” describes a compression of what nerve in its course through the cubital region?

Answer 20

Ulnar