Anatomy and Applied Anatomy of the Shoulder Joint

Introduction

The shoulder joint, also known as the glenohumeral joint, is one of the most mobile joints in the human body. It is primarily formed by three bones: the clavicle, scapula, and humerus, working together to allow a wide range of motion.

Bones Forming the Shoulder Joint

Clavicle (Collarbone)

• Acts as a strut, connecting the arm to the body.
• Protects neurovascular structures passing underneath.
• Forms the acromioclavicular and sternoclavicular joints.

Scapula (Shoulder Blade)

• Provides a stable base for arm movement.
• Forms the glenoid cavity where the humerus articulates.
• Contains important anatomical landmarks like the acromion and coracoid process.

Humerus (Upper Arm Bone)

• Articulates with the scapula at the glenoid cavity.
• Major contributor to shoulder movement.
• Forms the ball-and-socket nature of the shoulder joint.

Applied Anatomy of the Shoulder Joint

Joint Mechanics and Movements

The shoulder joint allows movements such as flexion, extension, abduction, adduction, internal and external rotation, and circumduction.

Clinical Relevance

• Dislocation: The shoulder is prone to dislocation due to its high mobility and relatively shallow glenoid cavity.
• Rotator Cuff Injuries: Damage to the rotator cuff muscles can affect stability and movement.
• Frozen Shoulder: Adhesive capsulitis leads to restricted movement and pain.

Conclusion

Understanding the anatomy and applied anatomy of the shoulder joint is essential for diagnosing and treating various conditions affecting mobility and function.