anatomy 8.2

What are the four regions of the upper limb?

Brachium (arm), antebrachium (forearm), wrist, and hand.

How many bones are in one upper limb?

30 bones.

How many humeri are in one upper limb?

1.

How many radius and ulna bones are in one upper limb?

1 radius and 1 ulna.

How many carpal bones are in one upper limb?

8.

How many metacarpals are in one upper limb?

5.

How many phalanges are in one upper limb?

14.

What is the humerus?

The longest and largest bone of the upper limb and the only bone of the brachium (arm).

What does the head of the humerus articulate with?

The glenoid cavity of the scapula.

What are the two tubercles of the humerus?

Greater tubercle and lesser tubercle.

Where is the greater tubercle located?

Laterally on the proximal humerus.

What helps form the rounded contour of the shoulder?

The greater tubercle.

Where is the lesser tubercle located?

Anteromedially on the proximal humerus.

What lies between the greater and lesser tubercles?

The intertubercular sulcus (bicipital sulcus or bicipital groove).

What structure passes through the intertubercular sulcus?

The tendon of the long head of the biceps brachii muscle.

What is the anatomical neck of the humerus?

A groove between the head and tubercles marking the former epiphyseal plate.

What is the surgical neck of the humerus?

A narrowing just distal to the tubercles.

Why is it called the surgical neck?

Because it is a common fracture site.

What is the deltoid tuberosity?

A roughened area on the lateral shaft of the humerus.

Which muscle attaches to the deltoid tuberosity?

Deltoid muscle.

What is the radial groove?

A groove near the deltoid tuberosity where the radial nerve and blood vessels travel.

Which bones form the elbow joint?

Humerus, radius, and ulna.

What are the medial and lateral epicondyles?

Bony projections on the distal humerus that serve as muscle attachment sites.

Which nerve passes behind the medial epicondyle?

The ulnar nerve.

What does the capitulum articulate with?

The head of the radius.

Where is the capitulum located?

On the lateral distal humerus.

What does the trochlea articulate with?

The trochlear notch of the ulna.

Where is the trochlea located?

On the medial distal humerus.

What does the radial fossa accommodate?

The head of the radius during elbow flexion.

What does the coronoid fossa accommodate?

The coronoid process of the ulna during elbow flexion.

What does the olecranon fossa accommodate?

The olecranon of the ulna during elbow extension.

Which forearm bone is lateral in anatomical position?

Radius.

Which forearm bone is medial in anatomical position?

Ulna.

What is the shape of the head of the radius?

Disc-shaped.

What does the head of the radius articulate with?

The capitulum of the humerus.