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Flashcards in Hand Deck (35)
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1
Q

How many bones are in the hand?

A

29 muscles, 19 bones, 19 articulations

2
Q

What joints are in the hand?

A

CMC, MCP, IP
-thumbs of 1 IP joint
Fingers have PIP and DIP

3
Q

What kind of joint is the CMC of the thumb?

A

saddle

4
Q

What is the characteristic feature of a saddle joint?

A

each articular surface convex in one dimension and concave in other

5
Q

The longitudinal diameter of articular surface of trapezium is what?

A

concave from palmar to dorsal to direction

6
Q

The transverse surface of the trapezium is?

A

convex in ML direction

7
Q

How many degrees of freedom does the CMC joint have?

A

2 degrees: abduction and adduction; flexion and extension

8
Q

Abduction and adduction of the CMC joint occurs in what plane?

A

sagittal

9
Q

Flexion and extension of the CMC joint occurs in what plane?

A

frontal

10
Q

What is the axis of rotation for the CMC joint?

A

passes through the convex member of articulation

11
Q

What does full extension of the CMC of the thumb stretch?

A

anterior oblique ligament (AOL), intermetacarpal ligament (IML) ad abductor pollicis musclw

12
Q

What are the arthokinematics of abduction at the CMC joint?

A

anterior roll, posterior slide

13
Q

What are the arthokinematics of adduction at the CMC joint?

A

posterior roll, anterior slide

14
Q

What is primarily responsible for active rolling of articular surface of thumb metacarpal

A

abductor pollicis longus

15
Q

What are the arthokinematics of flexion at the CMC joint?

A

roll and slide in medial direction (concvex on concave)

16
Q

What are the arthokinematics of extension at the CMC joint?

A

roll and slide in lateral direction (concave on convex)

17
Q

Where is the axis of rotation of the CMC of the thumb?

A

trapezium

18
Q

Flexion of the CMC joint of thumb causes elongation and slack of what:

A

radio collateral ligament

anterior oblique ligament

19
Q

Extension of the CMC joint of thumb causes elongation what:

A

anterior oblique ligament

20
Q

What planes do flexion and extension of the MCP joints occur:

A

sagittal plane

21
Q

What planes do abduction and adduction of the MCP joints occur:

A

frontal plane

22
Q

What are the arthrokinematics of the MCP joint in flexion:

A

roll and slide in same direction (concave on convex)

23
Q

What are the arthrokinematics of the MCP joint in extension:

A

roll and slide in same direction

24
Q

What must be activated in MCP flexion?

A

flexor digitorum profundus

25
Q

What is taut in MCP flexion?

A

dorsal capsule

radial collateral ligament

26
Q

What is extension of the MCP controlled by?

A

coactivation of extensor digitorum and one of intrisinc muscles of finger

27
Q

What is taut in MCP extension?

A

palmar plate taut

slack in radio collateral ligament

28
Q

What are the arthokinematics of abduction at the MCP joint?

A

roll and slide in same direction

29
Q

What are the arthokinematics of adduction at the MCP joint?

A

roll and slide in same direction

30
Q

Abduction of the MCP joint is powered by what?

A

first dorsal interosseus muscle

31
Q

What is taut and slack during abduction of the MCP joint?

A

taut: ulnar collateral ligament
slack: radio collateral ligament

32
Q

What is the AOR of abduction?

A

AP direction through the head of metacarpal

33
Q

What is the degree of freedom of IP joints?

A

one: flexion and extension

34
Q

What muscles power flexion of the IP joints of thumbs?

A
  • flexor pollicis longus

- flexor pollicis brevis

35
Q

What is the AOR for flexion and extension of the IP joints?

A

AP direction through convex members of joints