Anatomy of the Clavicle and Scapula

Study Notes

Clavicle (Collarbone)

S-shaped bone, connecting the sternum (breastbone) to the scapula (shoulder blade).
Acts as a strut, supporting the arm and transmitting forces from the upper limb to the axial skeleton.
Medial end articulates with the manubrium of the sternum.
Lateral end articulates with the acromion of the scapula.
Provides stability and allows for a wide range of arm movement.
Susceptible to fractures, particularly in the middle third.

Scapula (Shoulder Blade)

Large, flat, triangular bone, located posteriorly in the upper back.
Doesn't directly articulate with the axial skeleton; it is connected to the clavicle and humerus.
Glenoid cavity: shallow socket that articulates with the head of the humerus, forming the glenohumeral joint.
Acromion: prominent extension of the scapula that articulates with the clavicle at the acromioclavicular joint.
Coracoid process: projection that provides attachment points for muscles involved in moving the arm and shoulder.
Scapular spine: a prominent ridge that divides the posterior surface of the scapula into supraspinous and infraspinous fossae.
Subscapular fossa: a large medial depression on the anterior surface of the scapula.

Humerus

Long bone of the upper arm.
Proximal end: head (articulates with the glenoid cavity), anatomical neck, greater tubercle, lesser tubercle.
Distal end: medial and lateral epicondyles (projections for muscle attachments), trochlea (articulates with ulna), capitulum (articulates with radius).
Deltoid tuberosity: rough area on the lateral side of the shaft, where the deltoid muscle attaches.
Surgical neck: a constricted area near the juncture of the head and the shaft, a frequent fracture site.
Crucial for upper limb movement, acting as the major connecting bone to the forearm.

Radius

Lateral bone of the forearm.
Proximal end: head (articulates with the capitulum of the humerus), radial tuberosity (attachment for biceps).
Distal end: articulates with the scaphoid and lunate bones of the wrist.
Crucial for pronation and supination of the forearm.

Ulna

Medial bone of the forearm.
Proximal end: olecranon process (point of the elbow), coronoid process.
Distal end: styloid process (serves as an attachment point).
Trochlear notch: articulates with the trochlea of the humerus.
Crucial for pronation and supination of the forearm and for elbow stability.

Articulations/Joints

Glenohumeral joint (shoulder): Ball-and-socket joint, enables a wide range of motion.
Acromioclavicular joint: Plane joint between the acromion of the scapula and the clavicle.
Sternoclavicular joint: Saddle joint between the clavicle and sternum.
Elbow joint: Combination of hinge joints (humeroulnar and humeroradial) that enables flexion and extension.
Radiocarpal joint (wrist): Condyloid joint where radius and ulna articulate with the carpal bones, allowing flexion, extension, and circumduction.

Muscle Attachments

Numerous muscles are attached throughout the bones of the shoulder and arm, making them crucial for movement, stability, and support.
These attachments are vital for understanding and maintaining proper function.

Description

Explore the anatomy and functions of the clavicle and scapula. This quiz highlights their structural characteristics, connections, and roles in upper limb movement. Perfect for students studying human anatomy or preparing for related exams.