The key difference between coronoid and coracoid is their distribution; coronoid process is present as a pointed projection of the ulna while the coracoid process is present as a pointed projection of the scapula.
Movement and structure play important roles in the skeletal-muscular system. They facilitate various movements by attachment to numerous ligaments. Both coronoid and coracoid processes thus play an important role in facilitating movement.
CONTENTS
1. Overview and Key Difference
2. What is Coronoid
3. What is Coracoid
4. Similarities Between Coronoid and Coracoid
5. Side by Side Comparison – Coronoid vs Coracoid in Tabular Form
6. Summary
What is Coronoid?
Coronoid is present as a projection from the anterior proximal portion of the ulna. Therefore, it is called the ulna’s coronoid process. The base of the coronoid is continuous with the body of the bone while the apex is pointed and slightly curved upward. The upper surface of the coronoid is smooth and convex. The anteroinferior surface of the coronoid is concave. The lateral surface is narrow, oblong and has an articular depression. The prominent surface of the coronoid is the medial surface. It has a free margin and acts as the point of attachment to the ulnar collateral ligament.
Figure 01: Coronoid
The coronoid process also facilitates the attachment of the rounded bundle of muscle fibres known as the flexor pollicis longus muscle.
What is Coracoid?
The coracoid process is present on the edge of the scapula. It is placed at the lateral edge of the superior anterior part of the scapula. It is a pointed structure, and its main function is to stabilize the shoulder joint together with the acromion. Moreover, it is a thick process and is curved in nature. It is attached to the broad base of the upper part of the neck of the scapula. The structure of the coracoid varies when it develops. It becomes smaller and changes the direction and finally projects forward and laterally.
Figure 02: Coracoid
The coracoid has two main portions – the ascending portion and the horizontal portion. The medial portion is attached to the conoid ligament. The coracoid is also the site of attachment for several structures such as the pectoralis minor muscle, the biceps brachii muscle and the superior transverse scapular ligament.
What are the Similarities Between Coronoid and Coracoid?
- Coronoid and coracoid are pointed structures.
- Both facilitate attachment to ligaments.
- They have a basal surface followed by different phase surfaces.
- Moreover, they have curved edges.
- Both play an important role in movement and structure.
- They are prominent sites of injury, damage and fracture.
- Both can be characterized based on 3D image scanning technology.
What is the Difference Between Coronoid and Coracoid?
Often the coronoid and the coracoid processes are mistaken due to the similar structure and functions they show. However, there is a difference between coronoid and coracoid in their distribution and the attachments they facilitate. The coronoid process is present in the edge of the ulna while coracoids process is present on the edge of the scapula.
The below info-graphic summarizes the difference between coronoid and coracoids.
Summary – Coronoid vs Coracoid
The coronoid and coracoid are two processes that aid in the movement and maintenance of structures. These terms are often confused due to the similarity they show in structure. However, the key difference between coronoid and coracoids is their distribution. While the coronoid process is connected to the ulna, the coracoid process is connected with the scapula. Thus, the coronoid is also known as the ulna’s coronoid process, and the coracoid is known as the scapula’s coracoid process. They both are pointed and curved structures. They have unique features on their surfaces, and the attachments also vary among the two processes.
Reference:
Wells, Jason, and Robert H Ablove. “Coronoid Fractures of the Elbow.” Clinical Medicine & Research, Marshfield Clinic, May 2008, Available here.
Imma, I I, et al. “Coracoid Process Morphology Using 3D-CT Imaging in a Malaysian Population.” Malaysian Orthopaedic Journal, Malaysian Orthopaedic Association, July 2017, Available here.
Image Courtesy:
1. “Gray212” By Henry Vandyke Carter – Henry Gray (1918) Anatomy of the Human Body (See “Book” section below)Bartleby.com: Gray’s Anatomy, Plate 212 (Public Domain) via Commons Wikimedia
2. “Coracoid process of scapula – animation03” By BodyParts3D is made by DBCLS. – Polygon data is from BodyParts3D (CC BY-SA 2.1 jp) via Commons Wikimedia