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Triceps Brachii Muscle: Lateral Head

image descriptionTriceps Brachii Muscle: Lateral Head

The lateral head of the Triceps brachii, one of three heads of the muscle, originates from the humerus, superior to the radial groove to insert on the olecranon process.

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 (highlighted in green), Latissimus Dorsi, Triceps Brachii: Medial Head.
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 (highlighted in green), Latissimus Dorsi, Triceps Brachii: Medial Head.
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 (highlighted in green), Latissimus Dorsi, Triceps Brachii: Medial Head.
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image descriptionTriceps Brachii Muscle Lateral Head Attachments: Origin and Insertion

Origin (proximal attachment)
a. Proximal portion of posterior humerus, superior to radial groove.

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 (highlighted in green), Latissimus Dorsi, Triceps Brachii: Medial Head.
A posterior view of the upper arm and shoulder showing the bony elements and the attachment of the Triceps Brachii Lateral Head. Origin at the proximal portion of posterior humerus, superior to radial groove is marked by a red oval. The insertion at the posterior olecranon process of ulna is marked by a blue oval. Transparent Triceps Brachii Lateral Head connects the two attachment sites.
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Actions of the Triceps Brachii Muscle Lateral Head:

a.  image descriptionExtends the forearm the 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 Lateral 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 deeper muscles. The visible structures are numbered 1-2. The answers in the box below are as follows 1. Triceps Brachii: Long Head 2. Triceps Brachii: Lateral Head.
A test yourself image of the posterior view of the upper arm and shoulder showing the bony elements and the isolated Triceps Brachii Lateral 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 Lateral Head. Origin at the proximal portion of posterior humerus, superior to radial groove is marked by a red oval. The insertion at the posterior olecranon process of ulna is marked by a blue oval. Transparent Triceps Brachii Lateral Head connects the two attachment sites.
Test yourself while observing the Triceps Brachii muscle Lateral Head
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