Coracobrachialis Muscle Anatomy
- Location The coracobrachialis is located in the upper arm. ...
- Origin & Insertion The coracobrachialis originates at the coracoid process of the scapula and inserts at the midshaft of the humerus, which is distal to the crest of the lesser tubercle (the insertion is located between the attachments of the triceps brachii ’s medial head and the brachialis muscle) [2] .
- Actions ...
- Innervation ...
- Blood Supply ...
Which muscles originates on the coracoid process?
It is the site of attachment for several structures:
- The pectoralis minor muscle – to 3rd, 4th, 5th and on some rare occasions, 6th rib.
- The short head of biceps brachii muscle – to radial tuberosity.
- The coracobrachialis muscle – to medial humerus.
- The coracoclavicular ligament – to the clavicle. ...
- The coracoacromial ligament – to the acromion
- The coracohumeral ligament – to the humerus
How many muscles attach to the mastoid process?
The mastoid process serves for the attachment of the sternocleidomastoid, the posterior belly of the digastric muscle, splenius capitis, and longissimus capitis.
What muscle attaches to the coronoid process of ulna?
brachialis muscle. Radial notch – located on the lateral surface of the trochlear notch, this area articulates with the head of the radius. Tuberosity of ulna – a roughening immediately distal to the coronoid process. It is where the brachialis muscle attaches.
What muscles that retract the scapula?
- Function: Upper fibers elevate the scapula and rotate it during abduction of the arm (90 to 180 degrees) Middle fibers retract the scapula Lower fibers pull the scapula inferiorly.
- Origin: Skull, nuchal ligament and the spinous processes of C7 to T12
- Insertion: clavicle, acromion and the scapular spine
- Innervation: Accessory nerve (Cranial nerve XI)
What muscle inserts on the coracoid process of the scapula?
Pectoralis minor muscle – it inserts into the coracoid process. Its actions consist of protraction and depression of the scapula. The muscle is innervated by the medial pectoral nerve.
What structures attach to coracoid process?
The coracoid also serves as a critical anchor for many tendinous and ligamentous attachments. These include the tendons of the pectoralis minor, coracobrachialis, and short head of the biceps brachii muscles, and the coracoclavicular, coracohumeral, coracoacromial, and transverse scapular ligaments.
What ligaments and muscles attach on the coracoid process?
The muscles that are attached are: Pectoralis Minor, Coracobrachialis, and Biceps Brachii. In addition, this structure attaches all the tendons and ligaments together.
What is root in coracoid process?
On the medial part of the root of the coracoid process is a rough impression for the attachment of the conoid ligament; and running from it obliquely forward and lateralward, on to the upper surface of the horizontal portion, is an elevated ridge for the attachment of the trapezoid ligament.
What attaches to coronoid process?
At the junction of this surface with the front of the body is a rough eminence, the tuberosity of the ulna, which gives insertion to a part of the Brachialis; to the lateral border of this tuberosity the oblique cord is attached.
What articulates with the coracoid process?
The coracoid articulates with the forward edge of the sternum and with the scapula, humerus, and furcula.
What muscles attach to coronoid process of ulna?
MusclesPronator teres – the medial surface of the coronoid process.Flexor carpi ulnaris – olecranon process.Flexor digitorum superficialis – coronoid process.Flexor digitorum profundus – anteromedial surface.Pronator quadratus – distal anterior shaft.Extensor carpi ulnaris – posterior border.Supinator – proximal ulna.More items...•
What is the function of the coronoid process?
The coronoid process acts as a bony buttress to prevent posterior dislocation and has three soft tissue insertions which lend stability as well: the anterior joint capsule of the elbow, the brachialis muscle and the medial ulnar collateral ligament.
How many ligaments attach to the coracoid process?
two ligamentsCoraco-clavicular Ligaments (CCL): These two ligaments (trapezoid and conoid ligaments) attach the clavicle coracoid process of the scapula.
What does Corocoid mean?
Definition of coracoid : of, relating to, or being a process of the scapula in most mammals or a well-developed cartilage bone of many lower vertebrates that extends from the scapula to or toward the sternum.
What is the origin of the pectoralis minor muscle?
Description. The pectoralis minor is triangular in shape and is located under the pectoralis major, and both form the anterior wall of the axilla. It originates from the margins of the third to fifth ribs adjacent to the costochondral junction.
What type of muscle is the deltoid muscle?
Your deltoid muscles are in your shoulder, which is the ball-and-socket joint that connects your arm to the trunk of your body. Deltoid muscles help you move your arms in different directions. They also protect and stabilize your shoulder joint. Like most other muscles in your body, the deltoids are skeletal muscles.
How many ligaments attach to the coracoid process?
two ligamentsCoraco-clavicular Ligaments (CCL): These two ligaments (trapezoid and conoid ligaments) attach the clavicle coracoid process of the scapula.
What muscles attach to coronoid process of ulna?
MusclesPronator teres – the medial surface of the coronoid process.Flexor carpi ulnaris – olecranon process.Flexor digitorum superficialis – coronoid process.Flexor digitorum profundus – anteromedial surface.Pronator quadratus – distal anterior shaft.Extensor carpi ulnaris – posterior border.Supinator – proximal ulna.More items...•
What muscle inserts on the coronoid process of the ulna?
The brachialis had a musculoaponeurotic insertion onto the elbow capsule, coronoid, and proximal ulna.
What muscles attach to acromion process?
The deltoid muscle attaches to the acromion process, the primary muscle responsible for raising or abducting the arm. In humans, acromion processes can be flat, curved, hooked, or convex, depending on their shape.
What are the different types of attachments?
It is the site of attachment for several structures: 1 The pectoralis minor muscle – to 3rd, 4th, 5th and on some rare occasions, 6th rib. 2 The short head of biceps brachii muscle – to radial tuberosity. 3 The coracobrachialis muscle – to medial humerus. 4 The coracoclavicular ligament – to the clavicle. (The ligament is formed by the conoid ligament and trapezoid ligament .) 5 The coracoacromial ligament – to the acromion 6 The coracohumeral ligament – to the humerus 7 The superior transverse scapular ligament – from the base of the coracoid to the medial portion of the suprascapular notch
What is the coracoid process?
The coracoid process (from Greek κόραξ, raven) is a small hook-like structure on the lateral edge of the superior anterior portion of the scapula (hence: coracoid, or "like a raven's beak"). Pointing laterally forward, it, together with the acromion, serves to stabilize the shoulder joint.
Why is the surgeon's lighthouse called the surgeon's lighthouse?
It is otherwise known as the "Surgeon's Lighthouse" because it serves as a landmark to avoid neurovascular damage. Major neurovascular structures enter the upper limb medial to the coracoid process, so that surgical approaches to the shoulder region should always take place laterally to the coracoid process.
Which ligament is formed by the conoid ligament and trapezoid ligament?
The coracoclavicular ligament – to the clavicle. (The ligament is formed by the conoid ligament and trapezoid ligament .) The coracoacromial ligament – to the acromion. The coracohumeral ligament – to the humerus. The superior transverse scapular ligament – from the base of the coracoid to the medial portion of the suprascapular notch.
Which part of the coracoid process is an elevated ridge for the attachment of the trapezoi?
On the medial part of the root of the coracoid process is a rough impression for the attachment of the conoid ligament; and running from it obliquely forward and lateralward, on to the upper surface of the horizontal portion, is an elevated ridge for the attachment of the trapezoid ligament.
Which process changes direction?
The coracoid process is a thick curved process attached by a broad base to the upper part of the neck of the scapula; it runs at first upward and medialward; then, becoming smaller, it changes its direction, and projects forward and lateralward.
Which muscle is the site of attachment for the medial humerus?
The short head of biceps brachii muscle – to radial tuberosity. The coracobrachialis muscle – to medial humerus.
What is the coracoid process?
Coracoid process. The coracoid process is an anteriorly projecting hook-like process on the superolateral edge of the scapula that projects anterolaterally.
Which muscles are associated with the medial apex?
muscles: coracobrachialis from the medial apex. short head of biceps brachii from the lateral apex. pectoralis minor from the medial and upper part. ligaments: coracohumeral ligament. coracoclavicular ligament. coracoacromial ligament. superior transverse scapular (suprascapular) ligament.
What is the function of the coracobrachialis muscle?
The main function of the coracobrachialis muscle is to produce flexion and adduction of the arm at the shoulder joint. Along with the other flexors of the arm ( biceps brachii and brachialis muscles), coracobrachialis is innervated by the musculocutaneous nerve. In this article, we will discuss the anatomy and function of ...
What is the muscle that extends from the scapula to the shaft of the humerus?
Coracobrachialis muscle (Musculus coracobrachialis) The coracobrachialis is a long and slender muscle of the anterior compartment of the arm. As its name suggests, it extends from the coracoid process of scapula to the shaft of the humerus . The main function of the coracobrachialis muscle is to produce flexion and adduction ...
What muscle is used to pull the arm towards the trunk?
The main actions of the coracobrachialis muscle are bending the arm ( flexion) and pulling the arm towards the trunk ( adduction) at the shoulder joint. When the arm is abducted and extended, the coracobrachialis muscle acts as a strong antagonist to the deltoid muscle.
Which nerve innervates the coracobrachialis muscle?
Innervation. The coracobrachialis muscle is innervated by the musculocutaneous nerve (C5-C7) a branch of the lateral cord of the brachial plexus.
Where does the coracobrachialis originate?
Origin and insertion. The coracobrachialis is a slender muscle that originates from the deep surface of the coracoid process of scapula. The muscle fibers run inferolaterally towards the humerus. They insert onto the anteromedial surface of the humeral shaft, between the brachialis muscle and the medial head of triceps .
Can a rupture of the coracobrachialis cause entrapment?
In more severe cases the musculocutaneous nerve, which goes through the coracobrachialis, can become trapped ( entrapment ). Clinically, the affected patients show skin sensation disturbances on the radial part of the forearm and a weakened flexion in the elbow, as the nerve also supplies the biceps brachii and brachialis muscles. In contrast, an actual rupture of the coracobrachialis is extremely rare and almost only occurs in serious accidents .
Which nerve is used to insertion coracobrachialis?
The humeral insertion of coracobrachialis is crossed anteriorly by the median nerve. Along with the humerus, coracobrachialis forms the lateral border of the axilla, where it is also the easiest to palpate the muscle. Learn everything about the anatomy of the shoulder muscles with our study unit.
Overview
Function
It is the site of attachment for several structures:
• The pectoralis minor muscle – to 3rd, 4th, 5th and on some rare occasions, 6th rib.
• The short head of biceps brachii muscle – to radial tuberosity.
• The coracobrachialis muscle – to medial humerus.
Structure
The coracoid process is a thick curved process attached by a broad base to the upper part of the neck of the scapula; it runs at first upward and medialward; then, becoming smaller, it changes its direction, and projects forward and lateralward.
Anatomically it is divided into intervals of: base of coracoid process, angle of coracoid process, shaft and the apex of the coracoid process. The coracoglenoid notch is an indentation localized …
Clinical significance
The coracoid process is palpable just below the lateral end of the clavicle (collar bone). It is otherwise known as the "Surgeon's Lighthouse" because it serves as a landmark to avoid neurovascular damage. Major neurovascular structures enter the upper limb medial to the coracoid process, so that surgical approaches to the shoulder region should always take place laterally to the coracoid process.
Other animals
In monotremes, the coracoid is a separate bone. Reptiles, birds, and frogs (but not salamanders) also possess a bone by this name, but is not homologous with the coracoid process of mammals.
Analyses of the size and shape of the coracoid process in Australopithecus africanus (STS 7) have shown that in this species it displayed a prominent dorsolateral tubercle placed more laterally than in modern humans. This reflect, according to one interpretation, a scapula positioned high o…
Additional images
• Left scapula. Coracoid process shown in red.
• Animation. Coracoid process shown in red.
• Left scapula. Lateral view. Coracoid process shown in red.
External links
• Anatomy image: skel/scapula2 at Human Anatomy Lecture (Biology 129), Pennsylvania State University
• Coracoid Process - BlueLink Anatomy, University of Michigan Medical School