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Flashcards in 25 - Hand Deck (28)
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1
Q

What do I need to know?

A
  1. Bones in hand, how they articulate, movements allowed at each joint
  2. Muscles and tendons in palm
  3. Movements of thumb and fingers and muscles
2
Q

Bones of the palm?

A

MCs

3
Q

Why and how is the 1st MCJ an exception?

A
  • is very mobile
  • is a SADDLE joint (reciprocal concave and convex between trapezium and 1st MC)
  • permits as much movement as nearly ball in socket (flex/ext, abd/add, little rotation)
4
Q

The metacarpo-phalangeal joints (knuckles) are … joints and permit ……..

A

Condyloid joints and permit flexion/extension, abduction/adduction and some rotation

5
Q

The interphalangeal joints are … joints and permit …

A

Pure hinge joints and permit only flexion/extension

6
Q

Triaxial Joint?
Diaxial Joint?
Hinge Joint/uniaxial?

A

Moves in 3 planes (ball in socket) > femur
Moves in 2 planes > finger joints/MCP joints
Moves in 1 plane > elbow

7
Q

How does the 1st MCP joint differ from the others?

A

LESS movement

- only allows flexion/extension as is designed more like IP joint

8
Q

MCP joints?

A
  • condyloid joint
  • 1 curved condyle articulates with corresponding condyle
  • allows flex/ext and abd/add
9
Q

IP joints?

A
  • hinge joints (flex/ext) due to 2 condyles and 2 points of contact
10
Q

What prevents abduction/adduction at IP joints?

A

Collateral ligaments (and 2 condyles)

11
Q

What are the important ligaments of the finger?

A

There are 3

  1. Palmar Ligament
  2. Collateral ligaments
  3. Deep Transverse Metacarpal ligaments
12
Q

Collateral ligaments?

A

Sides of the MCP and IP joint capsules are thickened and are the main strengthening components of the joints

13
Q

Palmar Ligaments?

A

Soft felt-like channels on the anterior of the joints. They form the FLOOR of the interosseous tunnels which house the long flexor tendons

14
Q

What forms the floor of the fibrosseous tunnels and what do they do?

A

Palmar ligaments of anterior joints (MCP and IP). House the long flexor tendons

15
Q

Deep Transverse Metacarpal Ligaments?

A

Span the LATERAL 4 MCP joints to stop oversplaying of the hand/palm. Attach to the sides of the palmar ligaments

16
Q

Fibrosseous Tunnels?

A

Flexor tendons are wrapped in fibrous digital sheaths which attach to the palmar ligaments and bones to prevent bowstringing at the fingers
> beneath this they are wrapped in a bursa/synovial sheath which are slack enough to lubricate the tendons

17
Q

What tendons are in the common synovial sheath?

A

FDS and FDP

18
Q

What synovial sheath/bursa is in communication with the common synovial sheath around most of the flexor tendons at the carpal tunnel?

A

The little finger synovial sheath is. This means infection can be spread to the tendons at the carpal tunnel which can cause swelling - nerves and soft structures get compressed and damaged (Carpal Tunnel Syndrome)

19
Q

What flexor tendon has its own synovial sheath?

A

FPL

20
Q

Purpose of the intrinsic muscles of the hand?

A

To position the hand for power muscles to get a grip

21
Q

The interossei muscles pass on the … side of the …

A

Dorsal side of the transverse metacarpal ligaments

22
Q

What muscles abduct the fingers and how many are there?

A

DIMAB
Dorsal Interossei
4 (little and thumb don’t have)

23
Q

What muscles adduct the fingers and how many are there?

A
POMAD
4 (thumb is considered deep head of Flexor Pollicis Brevis as flexes doesn't adduct at 1st MCP joint)
24
Q

Dorsal Interossei?

A

> Insert Into the Midline and ABduct (DIMAB)

> bipennate (2 origins at the base of neighbouring MCs)

25
Q

Flexion of IP joints occurs by FDS and FDP but no forearm muscles inserts into PROXIMAL phalynx. Then how do the MCP joints flex?

A
  • partially by FDS and FDP during max shortening (tight fist)
  • fine control achieved by interossei and lumbricals with insertions into the DDEH
    > these muscles are complex and can flex the MCP joints while extending IP joints (pinch grip/thread a needle)
26
Q

Adductor Pollicis?

A
  • has own adductor as opposes fingers
    O: Metacarpals and carpals of MIDDLE finger
    I: Base of proximal phalynx
    > ulnar nerve
    > strongest intrinsic muscle
    > radial artery runs behind the base of the thumb and re-enters the hand between the 2 heads of the 1st dorsal interossei and 2 heads of adductor pollicis and then forms an arched arterial supply
27
Q

Does the little finger have its own adductor?

A

NO - it has its own abductor but not adductor. It has a palmer interossei. The THUMB has its own adductor

28
Q

Where does the radial artery run?

A

Runs behind base of thumb

Re-enters through 2 heads of 1st dorsal interossei and 2 heads of adductor pollicis