Anterior View of the Humerus: Borders and Surfaces Explained

The anterior view of the humerus showcases its borders and surfaces, providing key insights into the bone’s structure and its role in upper limb anatomy. This article offers a detailed examination of these features, serving as an essential resource for medical students seeking to master the humerus’s anatomical layout and clinical significance.

Labeled Anatomical Features

Lateral Border
The lateral border is the outer edge of the humeral shaft, extending from the greater tubercle proximally to the lateral epicondyle distally. It provides a structural boundary and serves as an attachment point for muscles like the brachioradialis.

- Advertisement -

Recommended Study Resource

Gray's Anatomy: The Anatomical Basis of Clinical Practice

Enhance your anatomical knowledge with Gray's Anatomy: The Anatomical Basis of Clinical Practice. This authoritative text offers in-depth insights and illustrations, perfect for medical students and practitioners aiming for clinical excellence.

Shop Now on Amazon Support Our Mission

At AnatomyNote.com, we offer free resources on anatomy, pathology, and pediatric medicine for medical students and professionals. Purchasing through our Amazon links, like Gray's Anatomy, supports our server costs and content creation at no additional cost to you.

Disclosure: As an Amazon Associate, we earn a commission from qualifying purchases.

Disclosure: As an Amazon Associate, we earn a commission from qualifying purchases at no extra cost to you.

Medial Border
The medial border runs along the inner edge of the humeral shaft, stretching from the lesser tubercle to the medial epicondyle. This border supports muscle origins, including the coracobrachialis and flexor carpi ulnaris, and helps define the bone’s medial surface.

Continuation of Crest of Greater Tubercle
The continuation of the crest of the greater tubercle extends down the anterior humeral shaft, marking the lateral lip of the intertubercular groove. This crest provides a continuous attachment site for the pectoralis major and deltoid muscles, aiding in arm movement.

Anterolateral Surface of the Humerus
The anterolateral surface of the humerus is the outer anterior face of the shaft, lying between the lateral border and the crest of the greater tubercle. It serves as an origin site for the brachialis muscle and is a key area for surgical approaches to the humerus.

Anteromedial Surface of the Humerus
The anteromedial surface of the humerus is the inner anterior face, situated between the medial border and the crest of the greater tubercle. This surface supports the origin of the brachialis and coracobrachialis muscles, contributing to elbow flexion and arm adduction.

- Advertisement -

Anatomy Flash Cards

Master anatomy with detailed, exam-ready flash cards.

Buy on Amazon Learn More

AnatomyNote.com offers free anatomy and pathology resources. Your purchase of Anatomy Flash Cards supports our site at no extra cost.

As an Amazon Associate, we earn from qualifying purchases.

Detailed Anatomy of the Anterior View of the Humerus

Overview of the Humerus

The humerus is the long bone of the upper arm, connecting the shoulder to the elbow with a distinct anterior view. This perspective highlights the borders and surfaces that are critical for muscle attachments and structural integrity, making it a foundational study area for medical students.

• The humerus comprises a proximal end, shaft, and distal end, each contributing to upper limb function.
• Its anterior surface is a primary site for muscle origins and insertions, influencing shoulder and elbow movements.
• The bone articulates with the scapula proximally at the shoulder joint and with the radius and ulna distally at the elbow.
• The shaft’s borders and surfaces provide a framework for understanding anatomical and clinical relationships.

Borders of the Humerus

The lateral and medial borders define the humeral shaft’s edges, playing a structural and functional role. These features are essential for mapping muscle attachments and surgical landmarks.

• The lateral border runs parallel to the shaft, offering a clear demarcation for lateral muscle attachments like the brachioradialis.
• The medial border provides a medial boundary, supporting muscles such as the coracobrachialis and flexor carpi ulnaris.
• Both borders converge at the proximal and distal ends, transitioning into the tubercles and epicondyles respectively.
• These borders help guide surgical approaches, such as those for humeral shaft fractures or nerve decompressions.

Surfaces of the Humerus

The anterolateral and anteromedial surfaces of the humerus are critical for muscle origins and overall arm function. These surfaces offer a detailed view of the bone’s anterior landscape for medical students.

• The anterolateral surface lies adjacent to the lateral border, serving as the origin for the brachialis muscle, which flexes the elbow.
• The anteromedial surface is positioned near the medial border, supporting the brachialis and coracobrachialis for elbow flexion and arm adduction.
• Both surfaces are covered by a thin layer of periosteum, which facilitates nutrient delivery and muscle attachment.
• The surfaces are relatively smooth, allowing for efficient muscle contraction without excessive friction.

Continuation of the Greater Tubercle Crest

The continuation of the crest of the greater tubercle extends the structural support of the proximal humerus down the shaft. This feature is vital for muscle dynamics and shoulder stability.

• The continuation of crest of greater tubercle marks the lateral lip of the intertubercular groove, guiding the pectoralis major tendon.
• It provides a continuous attachment for the deltoid muscle, enhancing arm abduction and flexion.
• The crest’s ridge-like structure strengthens the humeral shaft against torsional forces.
• This feature is a key landmark in imaging and surgical procedures targeting the proximal humerus.

Functional Role of the Humerus Surfaces and Borders

The borders and surfaces of the humerus facilitate a range of upper limb movements through their muscle attachments. This functionality is crucial for clinical and anatomical studies.

• The lateral border supports the brachioradialis, aiding in forearm flexion and rotation during gripping tasks.
• The medial border anchors the coracobrachialis, contributing to arm adduction and shoulder stabilization.
• The anterolateral and anteromedial surfaces provide origins for the brachialis, enabling strong elbow flexion for lifting.
• The continuation of the greater tubercle crest enhances shoulder abduction and internal rotation via the deltoid and pectoralis major.

Clinical Relevance of the Humerus Borders and Surfaces

The anterior view’s borders and surfaces are clinically significant due to their association with muscle injuries and fractures. This knowledge is essential for medical students learning diagnostics and treatment.

• Humeral shaft fractures can involve the lateral border or medial border, potentially damaging nearby nerves like the radial nerve.
• Muscle strains or tears, such as to the brachialis on the anterolateral surface, may result from overuse or trauma.
• The continuation of crest of greater tubercle is a reference point for assessing proximal humerus fractures or dislocations.
• Surgical approaches to the humerus often utilize these borders and surfaces to minimize damage to surrounding structures.

The anterior view of the humerus, with its distinct borders and surfaces, is a cornerstone of upper limb anatomy, supporting a range of movements and clinical considerations. For medical students, a thorough understanding of these features enhances their ability to diagnose and treat upper limb conditions, fostering a deeper appreciation of musculoskeletal health.