Accessory nerve location. accessorius), or the 11th cranial nerve (CN XI).

Accessory nerve location where is the accessory nerve nucleus located. Dec 21, 2023 · Each nerve has a name that reflects its function and a number according to its location in the brain. Vital signs are within normal range and he takes no medications other than ibuprofen to control pain. From here, the accessory nerve courses through the posterior triangle of the neck to enter the anterior border of the trapezius muscle at a point located approximately at the junction of the middle and lower thirds of the anterior border of this muscle. The nucleus of accessory nerve (a. 5], via Wikimedia Commons Sep 25, 2007 · The XIth cranial nerve or accessory nerve provides the motor supply to the sternocleidomastoid and trapezius muscles. They rejoin the vagus nerve and distribute to the same targets as the vagus. The accessory nerve is vulnerable to damage due to its superficial extracranial Nov 21, 2023 · The vagus nerve location originates in the brain and branches in different directions to the neck and trunk. It is a cranial nerve that serves the trapezius and sternocleidomastoid muscles. , In the context of shoulder girdle movements, which of the following terms refers to the movement of the scapula medially toward the spinal column, as in pinching the shoulder blades together?, List any The accessory nerve innervated the cucullaris musculature which is associated with neck movement and feeding behavior. Lynch, medical illustrator derivative work: Beao derivative work: Dwstultz [CC BY 2. doi:10. Johal J, Iwanaga J, Tubbs K, Loukas M, Oskouian RJ, Tubbs RS. Apr 16, 2018 · Included in this review, we mention variant anatomy, molecular development, histology, and imaging of the accessory nerve. It has a purely somatic motor function, innervating the sternocleidomastoid and trapezius muscles. The fibers that make up the accessory nerve enter the skull through the foramen magnum and proceed to exit the jugular foramen with cranial nerves IX and X. Motor rootlets originating from this nucleus form the spinal rootles of the accessory nerve, which ascend through the foramen magnum to enter the cranial cavity. As some roots begin arising below the skull, CN XI is the only cranial nerve that enters the skull passing through the foramen magnum. Two to 9 rootlets The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. Apr 16, 2018 · The accessory nerve (Fig. The cranial portion arises from LMNs at the caudal end of the nucleus ambiguus; the axons travel through an internal branch that distributes with the pharyngeal and laryngeal branches of the vagus nerve (CN X) and with nerves to the soft palate. It can suffer an injury with daily movements or behaviors that exceed the elastic capacity of the nerve structure, such as excessive stretching or carrying heavyweights. The spinal component originates from spinal nerve roots C1-C6 and innervates the sternocleidomastoid and trapezius muscles. It supplies motor fibers to all of the muscles of the tongue, with the exception of the palatoglossus muscle, which is innervated by the vagus nerve (cranial nerve X) or, according to some classifications, by fibers from the glossopharyngeal nerve (cranial nerve IX) that hitchhike within the In the posterior cervical triangle, we found that the suprascapular nerve could obtain enough nerve length, from its origin to the suprascapular notch, to perform suprascapular nerve-accessory nerve partial nerve transplantation and achieve tension-free suture, suggesting the feasibility of transplantation of the suprascapular nerve as a donor. a. The accessory nerve arises from a nucleus that overlaps portions of the upper cervical nerves. Apr 8, 2019 · The SAN is the 11th of 12 sets of cranial nerves. Branches of the vagus nerve include: While not as impressive, the accessory nerve, A 39-year-old man comes to the office for a follow-up visit two weeks after surgery to remove a benign growth under his jaw. Anatomy • The spinal accessory nerve arises from the cervical spinal cord (levels C-1–5) from a column of ventral horn cells that together are called the accessory nucleus (). The Spinal Accessory Nerve (SAN) or Cranial Nerve 11 is termed a cranial nerve as it was originally believed to originate in the brain. Following are the nuclei, functional components of accessory nerve: The fibers that form the spinal accessory nerve are formed by lower motor neurons located in the upper segments of the spinal cord. It has both a cranial and a spinal part, though debate still rages regarding whether the cranial part is a part of the SAN or part of the vagus nerve. Jul 13, 2021 · Most of the fibers of the accessory nerve originate in neurons situated in the upper spinal cord. Preganglionic neuron is located in the intermediolateral cell column of T1 spinal cord. That […] Nov 3, 2023 · Accessory nerve (CN XI) Cranial nerve 11 is an efferent nerve originating from the brainstem and spinal cord. The cranial component originates in the medulla and joins with the vagus nerve. a93e153b_admin . communication with the accessory nerve, whereas the C3 and C4 nerves innervate the muscle independently. Jun 3, 2018 · Spinal part aries from the spinal nucleus of accessory nerve located in upper 4-5 cervical segments of spinal cord. Materials and methods A retrospective review of 38 consecutive patients referred to a peripheral nerve surgical practice at an academic teaching hospital with surgically confirmed spinal accessory nerve injuries May 31, 2023 · Expanding what is known of the anatomy of the spinal accessory nerve: spinal accessory nerve revisited. Jul 17, 2023 · The accessory nerve provides motor function (movement) to two muscles essential to neck and shoulder movement, the sternocleidomastoid (SCM) and the trapezius, as well as to the larynx (voice box) and other structures in the throat. Anatomically, a distinction between the brainstem and spinal fibers is made. Jan 20, 2025 · The accessory nerve, also known as the eleventh cranial nerve (CN XI), is a unique cranial nerve that has both cranial and spinal roots. Functions • Special visceral efferent (SVE). The cranial root of the accessory nerve actually contributes to the vagus nerve and to the striated muscles of the pharynx, larynx, palate and oesophagus. The main part, the spinal portion, arises from a long column of nuclei situated in the ventral part of the medulla and extending to the fifth cervical segment or lower. The extension to the trapezius muscle serves as the ter-minal trunk of the accessory nerve (Alnot and Narakas, 1996). The Essential Guide to the Accessory Nerve: Functions, Disorders, and Treatment; spinal. The accessory nerve has cell bodies that are referred to as nucleus ambiguus and originate in the medulla oblongata. Nov 21, 2023 · Motor: Most of the motor supply to the trapezius muscle is derived from the accessory nerve, with contribution from the cervical plexus . M for motor. The spinal accessory nerve is composed of spinal roots which arise from motor neurons in the first through fifth cervical segments of the spinal cord. Recently, various surgical procedures have been devised that repurpose the accessory nerve (e. There are 12 pairs of cranial nerves, or nerves that emerge from the brain and extend into the Apr 12, 2019 · Accessory nerve. spinal accessory nucleus or accessory nucleus proper) is part of the central group of motor nuclei in the anterior gray horns of the cervical spinal cord. The accessory nerve is responsible for the motor innervation of the sternocleidomastoid and trapezius muscles. The primary sensory cells for vision are located within the retina, with the axons of the retinal ganglion cells forming the intraocular optic nerves (also called the optic nerve heads), which are normally not well seen at imaging. From a clinical perspective, this nerve is significant because it can be injured during surgical interventions involving the neck, namely in the posterior cervical triangle, potentially resulting in loss of movement of the aforementioned Most of the fibers of the accessory nerve originate in neurons situated in the upper spinal cord. The sternocleidomastoid muscle tilts and rotates the head, whereas the trapezius The spinal accessory nerve (SAN), the 11th cranial nerve (CNXI), has a long superficial course in the neck, which makes it vulnerable to injury that is rarely recognized. This nucleus is located within the cervical spinal cord, spanning from the levels of C1 to approximately C5 or C6. It crosses the posterior triangle in an oblique, inferoposterior direction, within the investing layer of fascia. Thereafter The accessory nerve, also referred to as the spinal accessory nerve, originates from the spinal accessory nucleus located in the posterolateral aspect of the anterior horns of the spinal cord at the levels C1 - C5 (or C6, C7). According to the generally accepted classification of functional components, it contains general somatic efferent fibers (GSE) and special visceral efferent fibers (SVE). After a signal reaches the accessory nerve nucleus in the anterior horn of the spinal cord, the signal is conveyed to motor endplates on the muscle The spinal part of the accessory nerve is also known as the spinal accessory nerve and it arises from the upper part of the cervical spinal cord from the spinal nerve roots, C1 to C5 or to C6 as well. Conclusions: The accessory nerve continues to be a topic of much discussion regarding its exact function and in particular to its cranial roots. So The cranial root of the accessory nerve originates from cells located in the caudal medulla. More recent anatomical texts differentiate between the two and describe the spinal accessory nerve as comprising two distinct portions (Alnot and Narakas, 1996; Benninger, 2015; Watkinson and Gleeson, 2016). Feb 10, 2025 · The accessory nerve (CN XI) exits the cranial cavity, descends down the neck, innervates sternocleidomastoid and enters the posterior triangle. Historically, the nerve was sacrificed on oncological grounds during radical neck dissection. It is frequently encountered during neck surgery, and as such is at risk of iatrogenic injury, resulting in the ‘shoulder syndrome’. The spinal accessory nerve is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. The accessory nerve: a comprehensive review of its anatomy, development, variations, landmarks and clinical considerations. It is primarily a motor nerve, supplying muscles involved in movements of the neck and shoulders. The spinal accessory nerve originates from the spinal accessory nucleus. Branchial motor to sternocleidomastoid and trapezius muscles. Jul 17, 2023 · The accessory nerve provides motor function (movement) to two muscles essential to neck and shoulder movement, the sternocleidomastoid (SCM) and the trapezius, as well as to the larynx (voice box) and other structures in the throat. Oct 30, 2023 · Motor neurons from each of the five upper cervical segments give rise to neuronal rootlets that protrude from the anterior surface of the spinal cord. The cranial part (accessory portion) is the smaller of the two. Dec 19, 2022 · The cranial nerves are twelve pairs that travel outside the skull via foramina to innervate various structures. Cranial part has its origin in the nucleus ambiguus located in medulla oblongata. Nerve fibers are distributed to effector organs along blood vessels. , lengthening procedures, contralateral neurotization procedures). The hypoglossal nerve controls tongue movements of speech, food manipulation, and swallowing. Feb 26, 2016 · 11 Spinal Accessory Nerve. They join the spinal root to exit the jugular foramen. The nerve fibers exit via the IX, X, XI complex. 2015;28(4):467-471. Postganglionic neuron is located in superior cervical ganglion of the sympathetic trunk. After leaving the skull, the spinal accessory nerve runs inferiorly and posteriorly. The accessory nerve supplies structures related to the fourth branchial arch. Oct 30, 2023 · Abducens nerve (cranial view) Spinal accessory nerve (CN XI) The spinal accessory nerve carries somatic efferent fibers to innervate the sternocleidomastoid and trapezius muscles. Feb 9, 2019 · Spinal Accessory Nerve Anatomy. Clin Anat. Recently, various surgical procedures have been devised that repurpose the The cranial portion of the accessory nerve is derived from the nucleus ambiguus and has been considered to be part of the vagal complex. Supranuclear innervation These unite as the accessory nerve (Fig. It exits the skull through the jugular foramen, acting to enable phonation and movements of the head and shoulders. The accessory nerve offers motion functions to the sternocleidomastoid muscles that extend from the neck and move to trapezius and then extends to the upper back and shoulder. Willis refers to the accessory nerve as an irregular spinal nerve, which supports the proposal that the accessory nerve is not of cranial origin. The accessory nerve was not classified as a cranial nerve by Thomas Willis, who is credited with the first accurate description of the nerve in humans. Jan 1, 2022 · Historically, the terms “accessory nerve” and “spinal accessory nerve” have been used interchangeably (Benninger, 2015). accessorius), or the 11th cranial nerve (CN XI). b. Sensory fibers of the cervical plexus join the accessory nerve enabling general sensation for its target muscles. Due to its unusual course, the accessory nerve is the only nerve that enters and exits the Jan 24, 2025 · Cranial Nerve XI (Accessory Nerve) Cranial nerve XI, the spinal accessory nerve, provides GSE motor innervation to the trapezius and sternocleidomastoid muscles via the spinal nucleus of the accessory nerve. Due to its unusual course, the accessory nerve is the only nerve that enters and exits the Study with Quizlet and memorize flashcards containing terms like What do both roots of the accessory nerve supply?, Where are the cell bodies located from the cranial root of the accessory nerve?, Where is the spinal nucleus of the accessory nerve located? and more. It was discovered that the spinal accessory nerve loses its cranial rootlets to the vagus nerve, which is located right above it. Number: XIName: Accessory (often separated into the cranial accessory and spinal accessory nerves)Sensory, motor, or both: Mainly motorOrigin/Target: Cranial and Spinal RootsNuclei: Nucleus ambiguus, Spinal accessory nucleusFunction: Controls the sternocleidomastoid and trapezius muscles, and overlaps with functions of the vagus nerve (CN X). To remember cranial nerve functions, the words in the mnemonic start with: S for sensory. In this note, we are going to discuss the anatomy and function of the accessory nerve (n. Its rootlets unite and ascend between the denticulate ligament and dorsal spinal rootlets. The smaller cranial part arises from cells in the nucleus ambiguus and ultimately is distributed with the vagus nerve. . 22492. Fibres exiting this nucleus from these spinal levels exit the superior cervical cord and lower medulla at the post-olivary sulcus. Mar 21, 2024 · Cranial nerve XI, the spinal accessory nerve (SAN), is vulnerable to injury, owing to its long and superficial course in the posterior cervical neck. The Accessory Nerve). 副神經（accessory nerve）是第11對腦神經，編號XI。它又可分成顱根（Cranial root）和脊髓根（Spinal root）兩條分支。 它又可分成顱根（Cranial root）和脊髓根（Spinal root）兩條分支。 The accessory nerve continues to be a topic of much discussion regarding its exact function and in particular to its cranial roots. The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. The accessory nerve is believed to have a universal presence in amphibians. The spinal accessory nerve derives from LMNs of the upper segments (C1–C4) of the cervical spinal cord; it ascends through the foramen magnus and emerges with cranial nerves IX and X through the jugular foramen. Mar 16, 2018 · Accessory Nerve Location and Origin. Oct 12, 2023 · The accessory nerve is the eleventh paired cranial nerve. B for both. Functionally and anatomically, the cranial accessory nerve is best considered a portion of the vagus nerve (Ryan et al, 2007). A comprehensive literature review and two cadaveric dissections were undertaken. Name the nuclei, functional components and structures supplied by accessory nerve . This cluster of neurons, called the spinal accessory nucleus, is located in the lateral horn of the spinal cord. Recently, Br ^ nzeu and Sindou (2017) intraoperatively mapped contributions to the accessory nerve using elec-tromyography. Jun 7, 2024 · Although discussion regarding the accessory nerve’s contribution has arisen on the basis of connections between the accessory nerve and vagus nerve in the posterior fossa being variable 5. By Patrick J. It was initially thought to be of the cranial nerve group, but now researchers aren’t so sure. Within the cranial cavity, the spinal Function. An important landmark in the neck, the SAN is considered to contribute most motor innervation to the trapezius muscle. 1), named after Thomas Willis (Willis, 1965) cranial nerve XI, innervates the sternocleidomastoid (SCM) and trapezius muscles. Symptoms of damage: inability to shrug, weak head Nov 21, 2023 · A nerve is a bundle of fibers that transmits signals to the brain, spinal cord, muscles, and organs. the sternocleidomastoid muscle acts in elevation of the thoracic cage and shoulder girdle, or, with fixation of the limb, will act in lateral flexion of the head to the shoulder on the same side and rotate the head to direct the chin upward to the opposite side. Therefore, the term “accessory” usually refers just to the nerve that supplies the sternocleidomastoid and trapezius muscles, also called the spinal accessory nerve. The word order mirrors the numerical order of nerves one through 12: Feb 12, 2025 · The cranial nerves are numbered by their location on the brainstem (superior to inferior, then medial to lateral) and the order of their exit from the cranium (anterior to posterior) (Figures 1 & 2). The vagal contribution to the pharyngeal plexus supplies the muscles of the pharynx except (stylopharyngeus) and the muscles of the soft palate (except Jan 5, 2017 · A = greater auricular nerve, B = lesser occipital nerve, C = transverse cervical nerve, C2–C5 = 2nd to 5th cervical nerves, D = supraclavicular nerve, DI = intermediate branch, DL = lateral branch, DM = medial branch, E = phrenic nerve, EJV = external jugular vein, F = ansa cervicalis, G = trapezius muscle, H = platysma, I = cervical branch Mar 7, 2017 · Optic nerve (CN II) The optic nerves, like the olfactory nerves, are not true peripheral cranial nerves but are instead extensions of the CNS. This portion innervates the pharyngeal muscles. it meets the cranial component of the accessory nerve and exits the skull along the The eleventh nerve has two parts. It is classified as the eleventh of twelve pairs of cranial nerves because part of it was formerly believed to originate in the brain. It innervates the sternocleidomastoid and trapezius muscles. Its fibers arise from the cells of the nucleus ambiguus and emerge as four or five delicate rootlets from the side of the medulla oblongata, below the roots of the vagus nerve. The accessory nerve enters the skull through the foramen magnum, only to turn and exit the cranium through the jugular foramen. This part of the accessory nerve is the one usually discussed in literature when talking about the nerve – the accessory nerve. 1002/ca. These Oct 14, 2022 · Functions. According to the morphology of the cranial root of the accessory nerve, it is made of the union of 2 to 4 short filaments, making the cranial roots of the accessory nerve. The internal carotid artery to reach both the sternocleidomastoid muscles and the trapezius. It’s important to note that in these mnemonics, “some” and “such” refer to another name for the accessory nerve: spinal accessory nerve. A few millimeters distal to the origin of the vagus is located the small proximal vagal ganglion (ganglion proximale n. The nucleus ambiguus is classically said to provide the "cranial component" of the accessory nerve . SAN was traditionally believed to be a pure motor nerve, but later anatomical studies have confirmed that it has both sensory and motor components Oct 14, 2022 · The accessory nerve, also called the spinal accessory nerve, or historically, the nerve of Willis, is the eleventh cranial nerve (CN XI) and is composed of two parts, the cranial part and the spinal part (TA: nervus accessorius or nervus cranialis XI). They are found in the nucleus ambiguus and leave the brainstem with the fibers of the vagus nerve. May 2, 2024 · The spinal accessory nerve, considered part of the eleventh cranial nerve, provides motor innervation to sternocleidomastoid and trapezius. The spinal accessory nerve can often be found 1 cm above Erb's point. In this article, we shall look at the anatomy of the accessory nerve – its anatomical course, motor functions and clinical correlations. vagi The fibers from the accessory nerve nucleus travel upward to enter the cranium via the foramen magnum. The fibers coming from the nuclei form delicate spinal rootlets emerging from the lateral surface of the spinal cord Oct 14, 2022 · Connections and course. Jul 18, 2016 · Close association of some of the vagal axons with those of the accessory (XI) nerve for a very short distance has led to the description of these vagal axons as part of the cranial root of the accessory nerve in some species. ¥: posterior belly of digastric muscle, ¶: external jugular vein; #: internal jugular vein; : accessory nerve; thin arrow: trapezial branch of accessory nerve; thick arrow: sternocleidomastoid branch of accessory nerve; *: great auricular nerve; ǂ: cutaneous branches of the cervical plexus nerves; blue arrow: PBD-SCMen The spinal accessory nucleus lies within the cervical spinal cord (C1-C5) in the posterolateral aspect of the anterior horn. This spinal accessory nucleus (also called the accessory nucleus proper) rarely extends beyond C5 but has been observed as low as C7. Study with Quizlet and memorize flashcards containing terms like \\In the context of shoulder girdle movements, an anterior tilt is a consequential rotational movement of the scapula ________. Curre … The cranial portion soon joins the vagus nerve, and it is debated whether or not the cranial portion should even be considered part of the accessory nerve. Injury can cause The accessory nerve (CN XI) is a motor nerve with cranial and spinal portions. Cranial nerve (CN) XI is also known as the accessory nerve (see Image. Sensory: Autonomic: Special senses: Other: The accessory nerve is the only cranial nerve which enters and exits the skull. Oct 22, 2021 · Objective To determine the accuracy of preoperative ultrasound and MRI in surgically confirmed spinal accessory nerve injuries and present the benefits of a multimodality image review. a. Jul 17, 2023 · The accessory spinal nerve or XI cranial nerve is essential for neck and shoulder movement, the intrinsic musculature of the larynx, and the sensitive afferences of the trapezius and sternocleidomastoid musculature. g. Sep 2, 2020 · The accessory nerve has both a spinal and cranial component. It is considered the eleventh of twelve pairs of cranial nerves, or simply cranial nerve XI, as part of it was formerly believed to originate in the brain. k. 1), which ascends in the spinal canal posterior to dentate ligaments and anterior to the dorsal roots. Thus, the fibers originating from the spinal cord are now termed the spinal accessory nerve. The spinal accessory nerve is located superficially in the posterior triangle of the neck, and you can identify it using two landmarks: one third of the way down from the posterior border of the sternocleidomastoid muscle and one third of the way up from the anterior border of the trapezius muscle. iqowbd btjsr mmtkefu bvofu yfpbx hsj ezcwgi afvg seydp bqm kstq mvrmrpo oiv lvcbbp mpf