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Triceps Brachii Muscle: Medial Head

image descriptionTriceps Brachii Muscle: Medial Head

The medial head of the Triceps brachii arises from inferior two thirds of humerus to insert, along with the other two heads of the triceps, on the olecranon of the ulna.

A posterior view of the upper arm and shoulder showing the bony elements and the associated muscles. The visible, labelled muscles are as follows: Trapezius, Deltoid, Teres Minor, Teres Major, Triceps Brachii: Long Head, Triceps Brachii: Lateral Head, Latissimus Dorsi, Triceps Brachii: Medial Head (highlighted in green).
A posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible, labelled muscles are as follows: Infraspinatus, Teres Minor, Teres Major, Triceps Brachii: Long Head, Triceps Brachii: Lateral Head, Latissimus Dorsi, Triceps Brachii: Medial Head (highlighted in green).
A posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible, labelled muscles are as follows: Teres Major, Triceps Brachii: Long Head, Triceps Brachii: Lateral Head, Latissimus Dorsi, Triceps Brachii: Medial Head (highlighted in green).
A posterior view of the upper arm and shoulder showing the bony elements and the associated muscles. The visible, labelled muscles are as follows: Trapezius, Deltoid, Teres Minor, Teres Major, Triceps Brachii: Long Head, Triceps Brachii: Lateral Head, Latissimus Dorsi, Triceps Brachii: Medial Head (highlighted in green).
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image descriptionAttachments of the Triceps Brachii Muscle Medial Head: Origin and Insertion:

Origin (proximal attachment)
a. Inferior 2/3 of posterior humerus.

Insertion (distal attachment)
a. Posterior olecranon process of ulna.

A posterior view of the upper arm and shoulder showing the bony elements and the associated muscles. The visible, labelled muscles are as follows: Trapezius, Deltoid, Teres Minor, Teres Major, Triceps Brachii: Long Head, Triceps Brachii: Lateral Head, Latissimus Dorsi, Triceps Brachii: Medial Head (highlighted in green).
A posterior view of the upper arm and shoulder showing the bony elements and the associated muscles. The visible, labelled muscles are as follows: Trapezius, Deltoid, Teres Minor, Teres Major, Triceps Brachii: Long Head, Triceps Brachii: Lateral Head, Latissimus Dorsi, Triceps Brachii: Medial Head (highlighted in green).
A posterior view of the upper arm and shoulder showing the bony elements and the attachment of the Triceps Brachii Medial Head. The area of origin at the inferior 2/3 of posterior humerus is highlighted in red. The insertion at the posterior olecranon process of the ulna is marked by a blue oval. Transparent Triceps Brachii Medial Head connects the two attachment sites.
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Actions of the Triceps Brachii Muscle Medial Head:

a.  image descriptionExtends the forearm at elbow.

Slide 1 of the animation showing forearm extension at the elbow.
Slide 2 of the animation showing forearm extension at the elbow.
Slide 3 of the animation showing forearm extension at the elbow.
Slide 4 of the animation showing forearm extension at the elbow.
Slide 5 of the animation showing forearm extension at the elbow.

Nerve to the Triceps Brachii muscle Medial Head and its spinal segment:

a. Radial nerve (C7, C8).

An overview of the posterior arm muscles

A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the associated soft structures. The visible structures are labelled 1-8 and the answers in the box below are concealed.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are labelled 1-8 The answers in the box below are as follows 1.Trapezius 2. Deltoid 3. Teres Minor 4. Teres Major 5. Triceps Brachii: Long Head 6. Triceps Brachii: Lateral Head 7. Latissimus Dorsi 8. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are labelled 1-9. The answers in the box below are as follows 1.Supraspinatus 2. Deltoid 3. Infraspinatus 4. Teres Minor 5.. Teres Major 6. Triceps Brachii: Long Head 7. Triceps Brachii: Lateral Head 8. Latissimus Dorsi 9. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are numbered 1-8. The answers in the box below are as follows 1. Supraspinatus 2. Infraspinatus 3. Teres Minor 4. Teres Major 5. Triceps Brachii: Long Head 6. Triceps Brachii: Lateral Head 7. Latissimus Dorsi 8. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are numbered 1-7. The answers in the box below are as follows: 1. Infraspinatus 2. Teres Minor 3. Teres Major 4. Triceps Brachii: Long Head 5. Triceps Brachii: Lateral Head 6. Latissimus Dorsi 7. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are numbered 1-7. The answers in the box below are as follows 1. Infraspinatus 2. Teres Minor 3. Teres Major 4. Triceps Brachii: Long Head 5. Triceps Brachii: Lateral Head 6. Latissimus Dorsi 7. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are numbered 1-6. The answers in the box below are as follows 1. Teres Minor 2. Teres Major 3. Triceps Brachii: Long Head 4. Triceps Brachii: Lateral Head 5. Latissimus Dorsi 6. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures of the forearm are numbered 1-5. The answers in the box below are as follows 1. Teres Major 2. Triceps Brachii: Long Head 3. Triceps Brachii: Lateral Head 4. Latissimus Dorsi 5. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are numbered 1-4. The answers in the box below are as follows 1. Triceps Brachii: Long Head 2. Triceps Brachii: Lateral Head 3. Latissimus Dorsi 4. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the deeper muscles. The visible structures are numbered 1-3. The answers in the box below are as follows 1. Triceps Brachii: Long Head 2. Triceps Brachii: Lateral Head 3. Triceps Brachii: Medial Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the isolated Triceps Brachii Medial Head labelled 1.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the attachment of the Triceps Brachii Medial Head. The area of origin at the inferior 2/3 of posterior humerus is highlighted in red. The insertion at the posterior olecranon process of the ulna is marked by a blue oval. Transparent Triceps Brachii Medial Head connects the two attachment sites.
Test yourself while observing the Triceps Brachii muscle Medial Head.
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