Hand and Wrist Lecture Flashcards Preview

Human Anatomy 1 -- Zach H. > Hand and Wrist Lecture > Flashcards

Flashcards in Hand and Wrist Lecture Deck (42):
1

Which joint is between the carpals and metacarpals? 

carpometacarpal joint

2

Which type of joint is between the metacarpals and phalanges?

metacarpophalangeal joint 

3

What joint is between phalanges (fingers)? 

interphalangeal joint

4

What joint is between the radius, scaphoid, and lunate? 

radiocarpal joint

5

What joint is between the distal carpal row and the proximal carpal row? 

midcarpal joint

6

When flexing the wrist, what percetage of flexion occurs at the radiocarpal join and percentage at the midcarpal joint?

  • radopcarpal joint = 40%
  • midcarpal joint = 60%

7

When extending the wrist joint, what percentage of extension is at the midcarpal joint, and which percentage is at the radiocarpal joint?

  • midcarpal joint = 33%
  • radiocarpal joint = 67% 

8

At which joint does most of the abduction and adduction of the wrist occur?

midcarpal joint

9

How many degrees of abduction (radial deviation) can be obtained at the wrist join? 

15-20 degrees 

10

How many degrees of adduction (ulnar deviation) can be obtained at the wrist joint?

30-45 degrees 

11

What is the degrees of ulnar deviation greater than the degrees obtained for radial deviation? 

The styloid of the radius blocks radial deviation at 20 degrees abducted. 

12

True or False: 

The extensor tendons form a immoveable hood over the MP and IP joints of the fingers called the extensor expansion. 

false - extensor tendons form a MOVEABLE hood over the MP and IP joints of the fingers called the extensor expansion. 

13

True or False: 

the arrangement of both extensor muscles and intrinsic hand muscles that attach to this dorsal digital expansion enable the uncoupling of flexion and extension. 

True 

14

What does the extensor hood mechanism allow?

this mechanism allows the long extensor tendos to strongly extend the MP joint and allows extension of IP joints when MP joints are flexed by lumbricals, which also attach to the "hood" part of the extensor expansion

15

What muscle is responsible for the "power grip", which is the powerful movement of digits 1-5? 

flexor digitorum profundus 

16

True or False: 

As the median nerve reaches the carpal tunnel, it moves from a position between f.d. superficialis and f.d. profundus, to a position superficial to f.d. superficialis. 

TRUE 

17

What is contained within the carpal tunnel?

  • median nerve 
  • flexor pollicis longus 
  • flexor carpi radialis 
  • flexor retinaculum 
  • flexor digitorum superficialis 
  • flexor digitorum profundus 

18

What wrist bones encircle half of the carpal tunnel? 

  • hamate 
  • capitate 
  • trapezoid 
  • trapezium 

19

What artery and nerve is found in Guyon's canal? 

ulnar nerve and artery 

20

What is the cause of Dupuytren's Contracture? 

Progressive shortening and thickening of the palmar fascia that pulls the 4th and 5th digits into partial flexion. 

Tends to be hereditary. 

21

What are the 5 fascial compartments of the hand and wrist? 

  • hypothenal compartment
  • thenar compartment 
  • central compartment 
  • adductor compartment 
  • interosseous compartment

22

Which long flexor tendons have a synovial sheath? 

  • flexor digitorum superficialis 
  • flexor digitorum profundus 
  • flexor pollicis longus 

23

Is the flexors pollicis longus' synovial sheath separate from the ulnar bursa?

Yes 

24

The long tendons of f.d. superficialis and profundus enter a common flexor sheath (ulnar bursa) beneath the flexor retinaculum. Each of their 4 tendons then enter its own separate synovial sheath. This synovial sheath is within a fibrous digital sheath. The synovial sheath for digit 5 is continuous with the ulnar bursa. 

25

What condition can be caused by an infection in the digital synovial sheaths?

Tensosynovitis 

 

** Infections in the digital synovial sheaths can cause inflammation of the tendon and synovial sheath. For the 5th digit, such an infection can spread into the carpal tunnel and into the forearm because the digital synovial sheath is continuous with the ulnar bursa **

26

Which 3 muscles form the thenar eminence? 

  • abductor pollicis brevis 
  • flexor pollicis brevis 
    • superficial head 
    • deep head 
  • opponens pollicis 

27

Which 4 muscles make up the intrinsic thenar muscles (thumb) of the palmar aspect of the hand (anterior)? 

  • abductor pollicis brevis 
  • flexor pollicis brevis 
    • superficial head 
    • deep head 
  • opponens pollicis 
  • adductor pollicis 
    • oblique head 
    • transverse head 

28

Which 3 muscles form the hypothenar eminence of the palmar aspect of hand (anterior)?

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

 

* palmaris brevis lies superficial

29

What is the proximal/distal attachments, actions, innervation, and blood supply of the opponens pollicis? 

Proximal Attachment: 

  • flexor retinaculum 
  • tubercles of scaphoid and trapezium 

Distal Attachment: 

  • lateral side of 1st metacarpal 

Actions:

  • oppose thumb
  • medially rotate 1st metacarpal 

Innervation:

  • recurrent branch of median nerve 

Blood Supply: 

  • superficial palmar branch of the radial artery 

30

What is the proximal/distal attachments, actions, innervation, and blood supply of the abductor pollicis brevis? 

Proximal Attachment: 

  • flexor retinaculum 
  • tubercles of scaphoid and trapezium 

Distal Attachment: 

  • lateral side of base of proximal phalanx of thumb 

Actions:

  • abduct thumb
  • aid in opposition 

Innervation: 

  • recurrent branch of median nerve 

Blood Supply:

  • superficial palmar branch of the radial artery 

31

What is the proximal/distal attachments, actions, innervation, and blood supply of the flexor pollicis brevis? 

Proximal Attachment:

  • flexor retinaculum
  • tubercles of scaphoid and trapezium 

Distal Attachment: 

  • lateral side of base of proximal phalanx of thumb

Actions:

  • flexes thumb

Innervation:

  • recurrent branch of median nerve (superficial head)
  • deep branch of ulnar nerve (deep head)

Blood Supply:

  • superficial palmar branch of the radial artery 

32

What is the proximal/distal attachments, actions, innervation, and blood supply of the adductor pollicis?

Proximal Attachment: 

  • bases of 2nd and 3rd metacarpals 
  • capitate
  • adjacent carpals

Distal Attachment:

  • medial side of base of proximal phalanx of thumb 

Actions: 

  • adducts thumb toward lateral border of palm

Innervation:

  • deep branch of ulnar nerve 

Blood Supply: 

  • deep palmar arterial arch 

33

What is the proximal/distal attachments, actions, innervation, and blood supply of the abductor digiti minimi?

Proximal Attachment: 

  • pisiform 

Distal Attachment: 

  • medial side of base of proximal phalanx of 5th digit

Actions:

  • abducts 5th digit
  • aids in flexion of 5th proximal phalanx

Innervation: 

  • deep branch of ulnar nerve 

Blood Supply: 

  • ulnar artery 

34

What is the proximal/distal attachments, actions, innervation, and blood supply of the flexor digiti minimi (brevis)?

Proximal Attachment: 

  • hook of hamate and flexor retinaculum 

Distal Attachment: 

  • medial side of base of proximal phalanx of 5th digit

Actions: 

  • flexes proximal phalanx of digit 5

Innervation: 

  • deep branch of ulnar nerve 

Blood Supply: 

  • ulnar artery

35

What is the proximal/distal attachments, actions, innervation, and blood supply of the opponens digiti minimi? 

Proximal Attachment: 

  • hook of hamate
  • flexor retinaculum 

Distal Attachment: 

  • medial border of 5th metacarpal

Actions:

  • brings 5th metacarpal anterior and rotates it to bring it into opposition with thumb

Innervation:

  • deep branch of ulnar nerve 

Blood Supply:

  • ulnar artery

36

What are the lumbrical intrinsic (short) muscles of the hand?

  • 1st and 2nd Lumbricals
    • ​attached to lateral 2 tendons of flexor digitorum pollicis
    • median nerve 
  • 3rd and 4th Lumbricals 
    • attached to medial 3 tendons of flexor digitorum pollicis 
    • deep branch of ulnar nerve 

 

They insert on the lateral sides of the extensor expansions of digits 2-5. 

They flex the metacarpophalangeal joints and extend interphalaneal joints (via the extensor expansion and extensor hood) of digits 2-5. 

 

37

What do the lumbrical intrinsic (short) muscles of the hand do? 

flex the metacarpophalageal joins and extend interphalangeal joints (via the extensor expansion and extensor hood) of digits 2-5

38

How many palmar interossei (PAD) intrinsic (short) muscles of the hand are there?

  • 3 of them 
  • attach to palmar surfaces of 2nd, 4th, and 5th metacarpals
  • insert at bases of proximal phalanges and the extensor expansions of digits 2nd, 4th, and 5th digits 
  • P.A.D. -> adduct 2nd, 4th, and 5th fingers toward axial line; also assist lumbricals 
  • innervated by deep branch of ulnar nerve 

39

How many dorsal interossei (DAB) intrinsic (short) muscles are there? 

  • 4 of them 
  • attach to adjacent sides of 2 metacarpals 
  • insert at bases of proximal phalanges and the extensor expansions of digits 2-4 
  • D.A.B. -> abduct 2nd-4th fingers toward axial line; also assist lumbricals 
  • innervated by deep branch of ulnar nerve

40

What nerve innervates the dorsal interossei (DAB) intrinsic (short) muscles of the hand? 

deep branch of ulnar nerve 

41

What nerve innervates the palmar interossei (PAD) intrinsic (short) muscles of the hand? 

deep branch of ulnar nerve 

42