bones of the upper limb

Question 1

What is the humerus, and where is it located?

Answer 1

The humerus is the largest bone in the upper limb, located between the shoulder and the elbow.

Question 2

With which bones does the humerus articulate?

Answer 2

The humerus articulates with the scapula at the glenohumeral joint and with the radius and ulna at the elbow joint.

Question 3

What structures are found at the proximal end of the humerus?

Answer 3

The proximal end of the humerus includes a head, anatomical neck, surgical neck, and greater and lesser tubercles.

Question 4

How does the head of the humerus function in articulation?

Answer 4

The spherical head of the humerus articulates with the glenoid cavity of the scapula, forming the glenohumeral joint.

Question 5

What is the anatomical neck of the humerus, and where is it located?

Answer 5

The anatomical neck is a groove that circumscribes the head of the humerus, separating it from the greater and lesser tubercles. It marks the line of attachment for the glenohumeral joint capsule.

Question 6

What is the significance of the surgical neck of the humerus?

Answer 6

The surgical neck is the narrow part of the humerus located distal to the head and tubercles and is a common site for fractures.

Question 7

What are the greater and lesser tubercles of the humerus?

Answer 7

The greater and lesser tubercles are bony prominences near the proximal end of the humerus, serving as attachment sites for muscles of the shoulder.

Question 8

What structures indicate the junction of the head and neck with the shaft of the humerus?

Answer 8

The greater and lesser tubercles indicate the junction of the head and neck with the shaft of the humerus.

Question 9

Where is the greater tubercle of the humerus located?

Answer 9

The greater tubercle is at the lateral margin of the humerus.

Question 10

Where is the greater tubercle of the humerus located?

Answer 10

The greater tubercle is located at the lateral margin of the humerus.

Question 11

Where is the lesser tubercle of the humerus located?

Answer 11

The lesser tubercle projects anteriorly from the humerus.

Question 12

What structure separates the greater and lesser tubercles of the humerus?

Answer 12

The intertubercular sulcus, also known as the bicipital groove, separates the greater and lesser tubercles.

Question 13

What is the function of the intertubercular sulcus (bicipital groove)?

Answer 13

It provides a protected passage for the tendon of the long head of the biceps brachii muscle.

Question 14

What are the two prominent features of the shaft of the humerus?

Answer 14

The deltoid tuberosity (laterally) and the radial groove (posteriorly).

Question 15

Where is the deltoid tuberosity located, and what is its function?

Answer 15

The deltoid tuberosity is located laterally on the humerus and serves as the attachment site for the deltoid muscle.

Question 16

What is another name for the radial groove on the humerus?

Answer 16

The radial groove is also known as the groove for the radial nerve or the spiral groove.

Question 17

How do the radial nerve and profunda brachii artery travel in relation to the triceps brachii muscle?

Answer 17

They pass anterior to the long head and between the medial and lateral heads of the triceps brachii muscle.

Question 17

What structures lie within the radial groove of the humerus?

Answer 17

The radial nerve and the profunda brachii artery lie in the radial groove.

Question 18

What happens to the shaft of the humerus as it approaches the distal end?

Answer 18

It widens, forming sharp medial and lateral supra-epicondylar (supracondylar) ridges.

Question 19

What do the medial and lateral supra-epicondylar ridges of the humerus lead to distally?

Answer 19

They end in the prominent medial and lateral epicondyles.

Question 20

What is the significance of the medial and lateral epicondyles of the humerus?

Answer 20

They provide attachment points for muscles of the forearm.

Question 21

What structures make up the condyle of the humerus?

Answer 21

The condyle of the humerus includes the trochlea, capitulum, olecranon fossa, coronoid fossa, and radial fossa.

Question 22

What are the two articular surfaces of the condyle of the humerus?

Answer 22

The lateral capitulum and the medial trochlea.

Question 23

What is the function of the capitulum on the humerus?

Answer 23

The capitulum (L. little head) articulates with the head of the radius.

Question 24

What is the shape and function of the trochlea on the humerus?

Answer 24

The trochlea is spool-shaped or pulley-like (L. pulley) and articulates with the trochlear notch of the ulna.

Question 25

What is the location and function of the coronoid fossa?

Answer 25

The coronoid fossa is located anteriorly, above the trochlea, and accommodates the coronoid process of the ulna during full flexion of the elbow.

Question 26

What is the location and purpose of the olecranon fossa?

Answer 26

The olecranon fossa is located posteriorly, above the trochlea, and accommodates the olecranon of the ulna during full extension of the elbow

Question 26

Where is the radial fossa located, and what is its function?

Answer 26

The radial fossa is located superior to the capitulum on the anterior side and accommodates the edge of the head of the radius during full flexion of the forearm.

Question 27

How do the coronoid fossa and olecranon fossa contribute to the structure of the condyle?

Answer 27

These fossae occur back to back, making the condyle thin between the epicondyles.