Muscles Of The Shoulder Region Flashcards

1
Q

Where is the elbow joint located?

A

The elbow joint is located 2–3 cm inferior to the epicondyles of the humerus.

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

What type of joint is the elbow joint?

A

The elbow joint is a hinge type of synovial joint.

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

What articulates in the humero-ulnar and humero-radial articulations of the elbow joint?

A

The spool-shaped trochlea of the humerus articulates with the trochlear notch of the ulna, and the spheroidal capitulum of the humerus articulates with the superior aspect of the head of the radius

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

What covers the articular surfaces of the elbow joint?

A

The articular surfaces are covered with hyaline cartilage.

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

When are the articular surfaces of the elbow joint most congruent?

A

The surfaces are most congruent when the forearm is flexed to a right angle and positioned midway between pronation and supination.

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

What does the fibrous layer of the joint capsule of the elbow joint do?

A

The fibrous layer surrounds the elbow joint and is attached to the humerus at the margins of the lateral and medial ends of the articular surfaces of the capitulum and trochlea.

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

How is the joint capsule of the elbow joint carried superiorly?

A

The joint capsule is carried superiorly, proximal to the coronoid and olecranon fossae.

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

What strengthens the joint capsule of the elbow joint on each side?

A

Collateral ligaments strengthen the joint capsule on each side.

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

Where is the synovial membrane of the elbow joint located?

A

The synovial membrane lines the internal surface of the fibrous capsule and the intracapsular non-articular parts of the humerus. It is also continuous with the synovial membrane of the proximal radio-ulnar joint.

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

What are the collateral ligaments of the elbow joint?

A

The collateral ligaments are strong triangular bands that are thickenings of the fibrous layer of the joint capsule.

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

Where does the radial collateral ligament extend from, and what does it blend with distally?

A

The radial collateral ligament extends from the lateral epicondyle of the humerus and blends distally with the anular ligament of the radius.

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

What is the function of the anular ligament of the elbow joint?

A

The anular ligament encircles and holds the head of the radius in the radial notch of the ulna, permitting pronation and supination of the forearm.

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

Where does the ulnar collateral ligament extend, and what does it consist of?

A

The ulnar collateral ligament extends from the medial epicondyle of the humerus to the coronoid process and olecranon of the ulna. It consists of three bands: the anterior cord-like band (strongest), posterior fan-like band (weakest), and slender oblique band.

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

What movements occur at the elbow joint?

A

Flexion and extension occur at the elbow joint.

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

What is the carrying angle of the elbow joint?

A

The long axis of the fully extended ulna makes an angle of approximately 170° with the long axis of the humerus.

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

How does the carrying angle of the elbow joint differ between men and women?

A

The carrying angle is approximately 10° more acute in women than in men.

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

When does the carrying angle of the elbow joint disappear?

A

The carrying angle disappears when the forearm is pronated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How many muscles cross the elbow joint and extend to the forearm and hand?

A

A total of 17 muscles cross the elbow joint and extend to the forearm and hand.

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

What are the chief flexors of the elbow joint?

A

The brachialis and biceps brachii are the chief flexors of the elbow joint.

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

What is the role of the brachioradialis in elbow flexion?

A

The brachioradialis can produce rapid flexion in the absence of resistance, even if the chief flexors are paralyzed.

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

Which muscles assist in producing slower flexion of the elbow joint under resistance?

A

The brachioradialis and pronator teres assist in producing slower flexion under resistance.

22
Q

What is the chief extensor of the elbow joint?

A

The triceps brachii, especially the medial head, is the chief extensor of the elbow joint.

23
Q

Which muscle weakly assists the triceps brachii in elbow extension?

A

The anconeus weakly assists the triceps brachii in elbow extension.

24
Q

What is the blood supply to the elbow joint?

A

The arteries supplying the elbow joint are derived from the anastomosis around the elbow joint.

25
Q

Which nerves supply the elbow joint?

A

The elbow joint is supplied by the musculocutaneous, radial, and ulnar nerves.

26
Q

What are the three olecranon bursae around the elbow joint?

A

The three olecranon bursae are:

1.	Intratendinous olecranon bursa (sometimes present in the triceps brachii tendon).
2.	Subtendinous olecranon bursa (located between the olecranon and triceps tendon).
3.	Subcutaneous olecranon bursa (located in the subcutaneous connective tissue over the olecranon).
27
Q

What is the function of the bicipitoradial bursa?

A

The bicipitoradial bursa separates the biceps tendon from the anterior part of the radial tuberosity and reduces abrasion.

28
Q

What type of joint is the proximal radio-ulnar joint?

A

The proximal radio-ulnar joint is a pivot type of synovial joint

29
Q

What articulates at the proximal radio-ulnar joint?

A

The head of the radius articulates with the radial notch of the ulna.

30
Q

How is the head of the radius held in position at the proximal radio-ulnar joint?

A

The head of the radius is held in position by the anular ligament of the radius.

31
Q

What does the joint capsule of the proximal radio-ulnar joint do?

A

The joint capsule encloses the joint and is continuous with the elbow joint capsule.

32
Q

What lines the deep surface of the joint capsule of the proximal radio-ulnar joint?

A

The synovial membrane lines the deep surface of the fibrous layer of the joint capsule and continues as the synovial membrane of the elbow joint.

33
Q

What is the function of the anular ligament at the proximal radio-ulnar joint?

A

The anular ligament surrounds the head of the radius, forming a collar that allows the radius to rotate within the radial notch.

34
Q

What movements occur at the proximal radio-ulnar joint?

A

Pronation and supination of the forearm occur at the proximal radio-ulnar joint.

35
Q

What happens to the radius during pronation and supination?

A

During pronation, the radius rotates around the ulna, and during supination, the radius uncrosses to a parallel position with the ulna.

36
Q

Which muscles produce supination at the proximal radio-ulnar joint?

A

The supinator and biceps brachii produce supination, with assistance from the extensor pollicis longus (EPL) and extensor carpi radialis longus (ECRL).

37
Q

Which muscles produce pronation at the proximal radio-ulnar joint?

A

The pronator quadratus primarily produces pronation, with assistance from the pronator teres.

38
Q

What is the blood supply to the proximal radio-ulnar joint?

A

The radial portion of the peri-articular arterial anastomosis of the elbow joint supplies the proximal radio-ulnar joint.

39
Q

Which nerves supply the proximal radio-ulnar joint?

A

The musculocutaneous, median, and radial nerves supply the proximal radio-ulnar joint.

40
Q

What type of joint is the distal radio-ulnar joint?

A

The distal radio-ulnar joint is a pivot type of synovial joint.

41
Q

What articulates at the distal radio-ulnar joint?

A

The rounded head of the ulna articulates with the ulnar notch on the medial side of the distal end of the radius.

42
Q

What is the main uniting structure of the distal radio-ulnar joint?

A

A fibrocartilaginous triangular articular disc, sometimes called the “triangular ligament,” binds the ends of the ulna and radius together.

43
Q

How does the joint cavity of the distal radio-ulnar joint appear in coronal section?

A

The joint cavity is L-shaped, with the vertical bar between the radius and ulna, and the horizontal bar between the ulna and the articular disc.

44
Q

What forms the fibrous layer of the joint capsule of the distal radio-ulnar joint?

A

The fibrous layer encloses the joint but is deficient superiorly

45
Q

What is the function of the sacciform recess in the distal radio-ulnar joint?

A

The sacciform recess accommodates the twisting of the capsule during pronation and supination.

46
Q

What ligaments strengthen the distal radio-ulnar joint?

A

The anterior and posterior ligaments strengthen the joint.

47
Q

What happens to the radius during pronation at the distal radio-ulnar joint?

A

The distal end of the radius moves anteriorly and medially, crossing over the ulna.

48
Q

What happens to the radius during supination at the distal radio-ulnar joint?

A

The radius uncrosses from the ulna, moving laterally and posteriorly.

49
Q

Which muscles are involved in moving the distal radio-ulnar joint?

A

The same muscles that move the proximal radio-ulnar joint also move the distal radio-ulnar joint.

50
Q

What is the blood supply to the distal radio-ulnar joint?

A

The anterior and posterior interosseous arteries supply the distal radio-ulnar joint.

51
Q

Which nerves supply the distal radio-ulnar joint?

A

The anterior and posterior interosseous nerves supply the distal radio-ulnar joint.