Upper Limb Overview, Clavicle & Scapula

What are the 4 main characteristics of the upper limb?

• Mobility

• Ability to grasp

• Ability to strike

• Fine motor skills (manipulation)

Which part of the upper limb demonstrates the greatest ability for fine motor skills?

The hand

Which 5 joints position the hand for efficient function?

• Scapulothoracic

• Glenohumeral (shoulder)

• Elbow

• Proximal & distal radioulnar (elbow and wrist joint)

• Wrist

What are the four segments of the upper limb?

• Shoulder

• Arm (brachium)

• Forearm (antebrachium)

• Hand (manus)

What bones are found in the arm?

The humerus.

What bones are found in the forearm?

• Radius

• Ulna

What bones make up the hand?

• Carpals

• Metacarpals

• Phalanges

What structures make up the hand?

• Wrist

• Palm

• Dorsum of hand

• Digits (including the opposable thumb)

Which sensory modalities are especially well developed in the hand?

• Touch

• Pain

• Temperature

What bones form the pectoral girdle?

• Two clavicles

• Two scapulae

What completes the pectoral girdle anteriorly?

The manubrium of the sternum.

How does the superior appendicular skeleton articulate with the axial skeleton?

Only at the sternoclavicular (SC) joint.

Which muscles support and move the pectoral girdle?

Axio-appendicular muscles.

What is another name for the clavicle?

Collar bone.

Which joints does the clavicle form?

• Sternoclavicular (SC) joint

• Acromioclavicular (AC) joint

Which bones does the clavicle articulate with?

• Manubrium of the sternum (medially)

• Acromion of the scapula (laterally)

Describe the shape of the clavicle.

An elongated S-shaped bone:

• Medial two-thirds convex anteriorly

• Lateral one-third concave anteriorly

What are the three main functions of the clavicle?

• Acts as a strut to hold the upper limb away from the thorax

• Transmits forces from the upper limb to the axial skeleton

• Forms part of the cervico-axillary canal

Why is the clavicle described as a strut?

It keeps the upper limb away from the thorax, allowing greater freedom of movement.

Why is the clavicle important during deep inspiration?

When fixed, it helps elevate the ribs.

What passes through the cervico-axillary canal?

The neurovascular bundle supplying the upper limb.

Why is the clavicle considered unusual for a long bone?

It has no medullary (marrow) cavity.

What type of bone tissue forms the clavicle?

Spongy (trabecular) bone surrounded by compact bone.

What type of bone is the scapula?

A triangular flat bone.

Where is the scapula located?

On the posterolateral thoracic wall, overlying ribs 2–7.

Which structure divides the posterior surface of the scapula?

The spine of the scapula.

Which fossae are found on the scapula?

• Supraspinous fossa

• Infraspinous fossa

• Subscapular fossa

Which fossa is found on the anterior (costal) surface of the scapula?

The subscapular fossa.

Name the borders of the scapula.

• Superior

• Medial (vertebral)

• Lateral (axillary)

Name the angles of the scapula.

• Superior angle

• Inferior angle

• Lateral angle (head of the scapula)

Which part of the scapula contains the glenoid cavity?

The lateral angle (head) of the scapula.

What is the neck of the scapula?

The narrowed region immediately medial to the head of the scapula.

Where is the suprascapular notch located?

On the superior border of the scapula, near the junction of the medial two-thirds and lateral one-third.

What does the spine of the scapula become laterally?

The acromion

What are the functions of the acromion?

• Forms the point of the shoulder

• Articulates with the clavicle at the AC joint

What is the glenoid cavity?

A shallow, oval socket that articulates with the head of the humerus.

In which direction does the glenoid cavity face?

• Anterolaterally

• Slightly superiorly

Why is the glenoid cavity important for shoulder mobility?

It is much smaller and shallower than the humeral head, allowing a large range of movement at the expense of stability.

Where is the coracoid process located?

Superior to the glenoid cavity, projecting anterolaterally

Compare the clavicle and scapula.

Clavicle	Scapula
Long bone	Flat bone
S-shaped	Triangular
Connects upper limb to trunk	Provides muscle attachment and shoulder socket
Forms SC & AC joints	Forms AC & glenohumeral joints
Acts as a strut	Forms the mobile base of the shoulder

Label

Label the numbers

Label

Label

Match each structure with its primary role:

• Clavicle

• Scapula

• Glenoid cavity

• Acromion

• Coracoid process

• Spine of scapula

Structure	Primary Role
Clavicle	Connects upper limb to trunk and acts as a strut
Scapula	Muscle attachment and glenoid socket
Glenoid cavity	Articulates with the humeral head
Acromion	Forms the point of the shoulder and AC joint
Coracoid process	Attachment site for muscles and ligaments
Spine of scapula	Divides the posterior surface into fossae