Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MSK > Anatomy 30 > Flashcards

Anatomy 30 Flashcards

1
Q

Give general features about the posterior forearm muscles

A
  • they are arranged in two layers: superficial and deep
  • most of them are extensors of the wrist, digits or thumb
  • they are all innervated by the radial nerve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 6 superficial muscles in the posterior compartment of the arm, from lateral to medial?

A
  • Brachioradialis
  • Extensor carpi radialis longus
  • Extensor carpi radialis brevis
  • Extensor digitorum
  • Extensor digiti minimi
  • Extensor carpi ulnaris
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the superficial muscles of the posterior compartment attached proximally to?

A

Lateral epicondyle of the humerus
– otherwise known as the ‘common extensor origin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is the brachioradialis an exception to the rules of the posterior compartment of the arm?

A

It acts as a weak flexor of the elbow joint and hence functions as an anterior compartment muscle.

However, it is innervated by the radial nerve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where does the brachioradialis lie?

A

On the boundary between the posterior and anterior compartments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where does the brachioradialis orginate from?

A

The humerus, proximal to the lateral epicondyle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where does the brachioradialis insert onto?

A

Distal radius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where do the Extensor carpi radialis longus (ECRL) and brevis (ECRB) lie?

A

On the radial side of the posterior compartment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does the Extensor carpi radialis longus (ECRL) insert onto?

A

2nd metacarpal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where does the Extensor carpi radialis brevis (ECRB) insert onto?

A

3rd metacarpal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What movements do the Extensor carpi radialis longus (ECRL) and brevis (ECRB) execute?

A

They extend and abduct the wrist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What movement does the Extensor digitorum (ED) execute?

A

Extends the digits via four long tendons that insert onto the dorsal aspects of the fingers (digits 2-5)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the tendons of the Extensor digitorum (ED) connected by?

A

Fibrous bands – this makes it difficult to fully extend the middle or ring fingers independently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What movement does the Extensor digiti minimi (EDM) execute?

A

Extends the little finger via its insertion onto the dorsum of the little finger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What movement does the Extensor carpi ulnaris (ECU) execute?

A

It extends and adducts the wrist via its insertion onto the 5th metacarpal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do the tendons of the superficial muscles of the posterior compartment of the arm travel?

A

Under a band of tissue, the extensor retinaculum.
It prevents the tendons from bowing when the wrist is extended

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the 5 deep muscles in the posterior compartment of the arm, from lateral to medial?

A
  • Supinator
  • Abductor pollicis longus
  • Extensor pollicis brevis
  • Extensor pollicis longus
  • Extensor indicis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where do the deep muscles in the posterior compartment of the arm, except for the supinator, attach proximally to?

A

To the forearm bones and the interosseous membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What 2 deep muscles in the posterior compartment of the arm are exceptions to the general rules?

A

Supinator
Abductor pollicis longus

They are not extensors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What movement does the supinator execute?

A

Supinates the forearm and hand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the supinator attached to proximally?

A

To the humerus
It wraps around the upper part of the radius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What movement does the abductor pollicis longus execute?

A

Abducts the thumb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the abductor pollicis longus insert onto?

A

1st metacarpal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What movement do the Extensor pollicis brevis (EPB) and extensor pollicis longus (EPL) execute?

A

Extend the thumb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does the Extensor pollicis brevis (EPB) insert onto?

A

Proximal phalanx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What does the Extensor pollicis longus (EPL) insert onto?

A

Distal phalanx, so is the only muscle capable of extending the interphalangeal joint of the thumb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What does the Extensor indicis (EI) insert onto?

A

Dorsum of the index finger, allowing independent extension of this digit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What muscles are seen on the dorsum of the hand?

A

4 dorsal interossei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Are the superficial veins of the dorsum of the hand visible?

A

Yes, they are often visible and palpable under the skin, they comprise the dorsal venous network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does the dorsal venous network drain into laterally?

A

Cephalic vein

31
Q

What does the dorsal venous network drain into medially?

A

Basilic vein

32
Q

What does the extensor expansion/extensor hood overlie?

A

The dorsal aspect of the digits

33
Q

What is the extensor expansion/extensor hood attached to?

A

The base of the proximal phalanx

34
Q

What does the extensor expansion/extensor hood give rise to?

A

A central slip and 2 marginal slips

35
Q

What does the central slip insert on?

A

The middle phalanx

36
Q

What do the marginal slips converge on?

A

The distal phalanx

37
Q

What do the tendons of ED, EI and EDM insert into?

A

The dorsal aspect of the extensor expansion,
this helps keep the tendons fixed in the midline of the digits

38
Q

What do the lumbricals and interossei insert into?

A

The sides of the proximal parts of the extensor expansion.

Via this attachment, they contribute to extension of the interphalangeal joints of the fingers.

39
Q

What is the anatomical snuffbox?

A

The anatomical snuffbox (ASB) is a triangular-shaped depression on the lateral aspect of the wrist, at the base of the thumb, seen when the thumb is extended

40
Q

What are the boundaries of the anatomical snuffbox?

A

The tendon of EPL medially and
the tendons of EPB and APL laterally

41
Q

Why is the anatomical snuffbox a clinically important region?

A
  • The scaphoid lies in the floor of the ASB.
    ASB tenderness on palpation may indicate a scaphoid fracture
  • The radial artery travels through it
  • The cephalic vein arises in the ASB; it can be cannulated here if necessary
42
Q

What nerve runs over the anatomical snuffbox?

A

The superficial branch of the radial nerve, to supply the skin over the lateral aspect of the dorsum of the hand

43
Q

Which artery and veins are associated with the posterior compartment of the posterior forearm?

A

Ulnar artery
Deep veins

44
Q

What are the major superficial veins of the forearm?

A

Cephalic and Basilic veins

45
Q

Where does blood from the dorsal venous network on the dorsum of the hand drain towards?

A

Cephalic and basilic veins

46
Q

What nerve innervates all the muscles of the posterior forearm?

A

Radial nerve

47
Q

What does the superficial branch of the radial nerve innervate?

A
  • The skin over the lateral aspect of the dorsum of the hand
  • Including the skin over the anatomical snuffbox
  • The skin over the dorsum of the lateral 3 ½ digits, as far as the DIP joint
48
Q

What type of joint is the shoulder joint?

A

Synovial ball and socket joint

49
Q

What is the shoulder joint formed by?

A

Articulation between the glenoid fossa of the scapula and the head of the humerus

50
Q

Describe some features of the shoulder joint

A
  • The articular surfaces of the shoulder are a poor fit – this compromises the stability of the joint but increases range of movement.
  • The joint capsule is lax, which allows mobility.
    It is reinforced by ligaments.
  • The glenoid is deepened by a rim of fibrocartilage – the glenoid labrum.
  • The rotator cuff is vital for stability at the shoulder joint.
  • The tendon of the long head of biceps contributes to stability at the joint.
51
Q

What type of joint is the elbow joint?

A

Synovial hinge joint

52
Q

What is the elbow joint formed by?

A
  • Articulations between the trochlea of the humerus - The trochlear notch of the ulna,
  • The capitellum of the humerus and the radial head
53
Q

What is the joint capsule of the elbow joint reinforced by?

A

Medial (ulnar) and
Lateral (radial) collateral ligaments

54
Q

What type of joints are the proximal and distal radioulnar joints?

A

Synovial, pivot-type joints between the
radius and ulna

55
Q

Describe the proximal and distal radioulnar joints

A

The radius rotates around the ulna when the forearm is pronated and supinated

56
Q

What is the anular ligament of the radius attached to?

A

Attached to the ulna and holds the radial head in place.
The radial head rotates within it to produce pronation and supination

57
Q

What type of joint is the wrist joint?

A

Condyloid synovial joint

58
Q

What is the wrist joint and carpus formed by?

A

Articulation of the distal radius with the scaphoid and lunate

59
Q

What is the wrist joint and carpus surrounded by?

A

Joint capsule which is reinforced by ligaments

60
Q

What type of joints are the intercarpal joints?

A

Synovial joints, which are also reinforced by ligaments

61
Q

What type of joints are the joints of the hand?

A

Synovial

62
Q

Where does the first carpometacarpal (CMC) joint lie?

A

Between the trapezium and the 1st metacarpal

63
Q

What type of joint is the first carpometacarpal (CMC) joint?

A

Saddle joint and is key to the range of movement possible at the thumb

64
Q

What type of joints are the metacarpophalangeal joints?

A

Condyloid joints

65
Q

What type of joints are the interphalangeal joints?

A

Hinge joints

66
Q

What is lateral epicondylitis?

A

The attachments of the extensor muscles to the lateral epicondyle may become inflamed.

Pain is felt over the region of the lateral epicondyle and may radiate down the forearm.

67
Q

What is lateral epicondylitis caused by?

A

Repetitive strain of the muscles and is also known as ‘tennis elbow

68
Q

What is radial head subluxation?

A

This is seen in young children and is caused by the child being suddenly pulled upwards by their arm.

The anular ligament is partially torn and the radial head moves out of the ligament.

It is painful and the child will not use their arm.
The subluxed head is reduced and the tear heals

69
Q

What is a wrist drop?

A

This describes an inability to extend the wrist (and fingers) due to weakness or paralysis of the posterior forearm muscles

70
Q

What is wrist drop a result from?

A

Results from injury to the radial nerve proximal to the forearm

71
Q

What is wrist drop typically caused by?

A

A mid-shaft humeral fracture, as the radial nerve lies close to the bone here.

Sensation is also impaired over the lateral aspect of the dorsum of the hand (i.e. in the regions of skin of the hand supplied by the radial nerve).

72
Q

What is injury to the extensor tendons?

A

The tendons lie relatively superficially over the dorsum of the hand and are vulnerable to injury from lacerations.

73
Q

What is osteoarthritis?

A

Is ‘wear and tear’ arthritis and is more common in older people. It affects large and small joints.

In the hands, it predominantly affects the PIP and DIP joints and bony swellings are seen at the joints.

74
Q

What is rheumatoid arthritis?

A

Is an autoimmune condition.
It affects synovial joints and the small joints of the hands and feet are typically involved.

The MCP and PIP joints are predominantly affected. Rheumatoid arthritis can destroy these joints causing significant deformity and functional impairment.

Early treatment prevents these joint complications

MSK (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions