Gross Lecture 3

Question 1

What are the names of the 8 carpal bones?

Answer 1

scaphoid, lunate, triquetrium, pisiform, trapezium, trapezoid, capitate, hamate

Question 2

What forms the hypothenar eminence?

Answer 2

3 muscles on the ulnar side of the pinkie finger (5th digit)

• abductor digiti minimi
• flexor digiti minimi
• opponens digit minimi

Question 3

What articulates with the distal ulna?

Answer 3

triangular fibrocartilaginous disc separating the distal ulna and the triquetrum bone - keeps the ulna from moving when the wrist moves

Question 4

Which muscle attaches to the tendons of flexor digitorum profundus?

Answer 4

lumbricals

Question 5

Which nerve innervates the thenar eminence? Hypothenar eminence?

Answer 5

thenar eminence: recurrent branch of the median nerve

hypothenar: deep branch of the ulnar nerve

Question 6

Where does the primary contribution to the deep palmar arch come from?

Answer 6

radial artery

Question 7

What is the innervation of the adductor pollicis?

Answer 7

ulnar nerve

*the only thumb muscle innervated by ulnar

Question 8

Which muscles attach to the dorsal digital expansion?

Answer 8

extrinsic extensor tendons, lumbricals, interossei

Question 9

How do the lumbricals cause extension of the interphalangeal joints?

Answer 9

the lumbricals join the expansion distal to interossei (flexors of the metacarpophalangeal joints) and affect the central and lateral bands to extend teh interphalangeal joints when the metacarpophalangeal joints are flexed

Question 10

What deformity will occur with rupture of the lateral bands? Central bands?

Answer 10

lateral bands: Mallet finger (DIP cannot be extended)

central bands: boutonniere deformity (PIP is flexed while DIP is extended)