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Lesser Auricular Nerve
The lesser auricular nerve originates from the cervical plexus, composed of branches of spinal nerves C2 and C3. Therefore, the "Great auricular nerve" is incorrectly named "Greater auricular nerve". The runs posteriorly to the ear, and is "greater," since it provides most of the to the ear: the back of the ear, front of the ear and earlobe. The rest is provided by the |
Cervical Plexus
The cervical plexus is a plexus of the anterior rami of the first four cervical spinal nerves which arise from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the medial side and vertebral (m. scalenus, m. levator scapulae, m. splenius cervicis) from lateral side. There is anastomosis with accessory nerve, hypoglossal nerve and sympathetic trunk. It is located in the neck, deep to the sternocleidomastoid muscle. Nerves formed from the cervical plexus innervate the back of the head, as well as some neck muscles. The branches of the cervical plexus emerge from the posterior triangle at the nerve point, a point which lies midway on the posterior border of the sternocleidomastoid. Branches The cervical plexus has two types of branches: cutaneous and muscular. *Cutaneous (4 branches): **Lesser occipital nerve - innervates the skin and the scalp posterosuperior to the auricle (C2) **Great auricular nerve - ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Nerve
A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the corresponding cervical, thoracic, lumbar, sacral and coccygeal regions of the spine. There are eight pairs of cervical nerves, twelve pairs of thoracic nerves, five pairs of lumbar nerves, five pairs of sacral nerves, and one pair of coccygeal nerves. The spinal nerves are part of the peripheral nervous system. Structure Each spinal nerve is a mixed nerve, formed from the combination of nerve fibers from its dorsal and ventral roots. The dorsal root is the afferent sensory root and carries sensory information to the brain. The ventral root is the efferent motor root and carries motor information from the brain. The spinal nerve emerges from the spinal column through an opening (intervertebral foramen) between adjacent vertebrae. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Auricular Nerve
The great auricular nerve is a cutaneous nerve of the head. It originates from the cervical plexus, with branches of spinal nerves C2 and C3. It provides sensory nerve supply to the skin over the parotid gland and the mastoid process of the temporal bone, and surfaces of the outer ear. Pain resulting from parotitis is caused by an impingement on the great auricular nerve. Structure The great auricular nerve is the largest of the ascending branches of the cervical plexus. It arises from the second and third cervical nerves. It winds around the posterior border of the sternocleidomastoid muscle, and, after perforating the deep fascia, ascends upon that muscle beneath the platysma muscle to the parotid gland. Here, it divides into an anterior and a posterior branch. Branches * The anterior branch (ramus anterior; facial branch) is distributed to the skin of the face over the parotid gland. It communicates with the facial nerve inside the parotid gland. * The posterior branch ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Innervation
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon, within the nerve, is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Within a nerve, each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. Finally, the entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auriculotemporal Nerve
The auriculotemporal nerve is a branch of the mandibular nerve (CN V3) that runs with the superficial temporal artery and vein, and provides sensory innervation to various regions on the side of the head. Structure Origin The auriculotemporal nerve arises from the mandibular nerve (CN V3). The mandibular nerve is a branch of the trigeminal nerve (CN V), and the mandibular nerve exits the skull through the foramen ovale.Gray's Anatomy for Students, 2nd edition (2010), Drake Vogel and Mitchell, Elseview These roots encircle the middle meningeal artery (a branch of the mandibular part of the maxillary artery, which is in turn a terminal branch of the external carotid artery). The roots encompass the middle meningeal artery then converge to form a single nerve. Course The auriculotemporal nerve passes between the neck of the mandible and the sphenomandibular ligament. It gives off parotid branches and then turns superiorly, posterior to its head and moving anteriorly, giv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
