Name: spinal nerve plexuses of the neck and arm
Uploaded: 2024-03-28T14:28:35.000Z
Duration: 1 min 22 s
Channel: JoVE

K12 Standards

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

9-12

Human Anatomy and Physiology

Integration And Coordination

Nervous System

Spinal Nerves: Plexus I

A plexus is an axon network of the anterior rami of nerves from different spinal regions, except for thoracic nerves T2 to T12, which form the intercostal nerves.
The first four and partly the fifth cervical spinal nerves in the neck region form the cervical plexus. It innervates the skin and muscles in the head, neck, and shoulders.
The phrenic nerve is a crucial motor nerve of the cervical plexus. It innervates the diaphragm, controlling the breathing movements.
The other two motor nerves in the cervical plexus are the ansa cervicalis, and segmental branches.
Additionally, the cervical plexus has four sensory nerves &#8212; the lesser occipital, great auricular, transverse cervical, and supraclavicular.
The brachial plexus is situated partially in the neck and axilla. This provides nerve supply to the shoulder and upper limbs.
The brachial plexus mainly arises from the fifth to eighth cervical nerves and the first thoracic nerve.
Of these brachial nerves, the axillary, musculocutaneous, radial, median, and ulnar are the five significant nerves responsible for most of the shoulder, hand, and finger movements.

spinal nerves: plexus i

Nerve plexuses are networks of interlacing nerves that serve as communication hubs to distribute and organize nerve action across various body regions. The nerve plexuses are organized into the cervical plexus located in the neck region, brachial plexus in the shoulder area, lumbar plexus found in the lower back, sacral plexus situated in the pelvis, and coccygeal plexus located in the coccygeal region.
The Cervical Plexus
The cervical plexus, formed by the anterior rami of the first four cervical spinal nerves (C1-C4), and partially the fifth cervical spinal nerve (C5), is situated in the neck region. This plexus innervates the skin and muscles of the head, neck, and shoulders, facilitating both sensory and motor functions.
<ul>
	<li>&#8226; Motor Innervation: The phrenic nerve is a primary motor nerve emerging from the cervical plexus. It innervates the diaphragm and is essential in controlling the respiratory process. Without the proper function of this nerve, breathing would be significantly impaired.</li>
</ul>
Other motor components of the cervical plexus include the ansa cervicalis and segmental branches. The ansa cervicalis innervates some infrahyoid muscles, aiding in swallowing and speech. The segmental branches supply motor fibers to the deep muscles of the neck, contributing to the stability and movement of the head.
<ul>
	<li>&#8226;&#160;Sensory Innervation: The cervical plexus also comprises four primary sensory nerves: the lesser occipital, great auricular, transverse cervical, and supraclavicular nerves. These nerves provide sensation to the skin of the neck, ear area, and parts of the shoulder and chest, ensuring sensory input from these regions reaches the central nervous system.</li>
</ul>
The Brachial Plexus
The brachial plexus extends from the neck into the axilla and is formed by the anterior rami of the fifth to eighth cervical nerves (C5-C8) and the first thoracic nerve (T1). This plexus supplies the shoulder and upper limbs, orchestrating a wide range of movements and sensory functions. The brachial plexus gives rise to five significant nerves:
<ul>
	<li>&#8226;&#160;Axillary Nerve: This innervates the deltoid and teres minor muscles, enabling shoulder abduction and playing a role in the sensation of the shoulder area.</li>
	<li>&#8226;&#160;Musculocutaneous Nerve: This nerve supplies the flexor muscles in the front of the arm, facilitating elbow flexion, and provides sensory information from the lateral forearm.</li>
	<li>&#8226;&#160;Radial Nerve: By innervating the muscles on the posterior aspect of the upper limb, this nerve supports elbow extension, wrist and finger extension, and thumb abduction. It also conveys sensory input from the posterior arm and hand.</li>
	<li>&#8226;&#160;Median Nerve: This nerve is primarily responsible for flexing the wrist and fingers, along with thumb opposition. It also carries sensory information from the palmar aspect of the hand.</li>
	<li>&#8226;&#160;Ulnar Nerve: The intricate movements of the fingers and wrist are controlled by this nerve. It provides sensation to the little finger and part of the ring finger, highlighting its importance in grip and hand movements.</li>
</ul>

A plexus is an axon network of the anterior rami of nerves from different spinal regions, except for thoracic nerves T2 to T12, which form the intercostal ...

Education

JoVE Core

Anatomy and Physiology

Unit 1

Anatomy of the Central and Peripheral Nervous System

anatomy-of-the-central-and-peripheral-nervous-system

KEY TERMS AND CONCEPTS

spinal nerve plexuses of the neck and arm

Spinal nerve plexuses are networks of interlacing nerves that organize nerve signals across the body. They act as communication hubs and are grouped into the cervical plexus in the neck, the brachial plexus in the shoulder area, the lumbar plexus in the lower back, the sacral plexus in the pelvis, and the coccygeal plexus in the coccyx region.

The cervical plexus is formed by the anterior rami of the first four cervical spinal nerves, C1 to C4, with some input from C5. It lies in the neck region and supplies the skin and muscles of the head, neck, and shoulders. This plexus carries both sensory and motor information.

One important motor nerve from the cervical plexus is the phrenic nerve. It controls the diaphragm and helps with breathing. The cervical plexus also includes the ansa cervicalis and segmental branches. The ansa cervicalis supplies some infrahyoid muscles, which help with swallowing and speech, while the segmental branches supply deep neck muscles that support head movement and stability.

The cervical plexus also has four main sensory nerves. These are the lesser occipital, great auricular, transverse cervical, and supraclavicular nerves. They provide sensation from the skin of the neck, ear area, and parts of the shoulder and chest, and they carry that sensory input to the central nervous system.

The brachial plexus extends from the neck into the axilla, or armpit, and is formed by the anterior rami of C5 to C8 and T1. It supplies the shoulder and upper limb, where it supports many movements and sensory functions. From this plexus come five major nerves: the axillary, musculocutaneous, radial, median, and ulnar nerves.

The axillary nerve innervates the deltoid and teres minor muscles and helps with shoulder abduction. The musculocutaneous nerve supplies the front arm flexor muscles, which support elbow flexion, and it also carries sensory information from the lateral forearm. The radial nerve supplies muscles on the back of the upper limb and supports elbow extension, wrist and finger extension, and thumb abduction, while also carrying sensory input from the posterior arm and hand.

The median nerve helps flex the wrist and fingers and allows thumb opposition. It also carries sensory information from the palm side of the hand. The ulnar nerve controls fine movements of the fingers and wrist and provides sensation to the little finger and part of the ring finger, which makes it important for grip and hand movement.

Spinal Nerve Plexuses of the Neck and Arm

anatomy of the brain: major regions

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Spinal nerve plexuses are networks of interlacing nerves that organize nerve signals across the body. They act as communication hubs and are grouped into the cervical plexus in the neck, the brachial plexus in the shoulder area, the lumbar plexus in the lower back, the sacral plexus in the pelvis, and the coccygeal plexus in the coccyx region. The cervical plexus is formed by the anterior rami of the first four cervical spinal nerves, C1 to C4, with some input from C5. It lies in the neck...

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key terms and concepts

Explore the cervical and brachial plexuses, including key nerves such as the phrenic, radial, median, and ulnar nerves, in the neck and upper limb.

Spinal Nerve Plexuses of the Neck and Arm | JoVE K12

anatomy and physiology

JoVE Core Anatomy and Physiology showcases the anatomical and physiological details of the human body in comprehensive, clear, and engaging video animations. This collection of lessons focuses on the structures, components, functions, and requirements of the human body. It is complemented by scientist-in-action videos that demonstrate the application of this knowledge in real-world medical and research settings.

Florida Department of Education

High School

Life Science

SC.912.L.14

SC.912.L.14.21

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Spinal Nerve Plexuses of the Neck and Arm

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