which cranial nerve controls the trapezius and sternocleidomastoid muscles?which cranial nerve controls the trapezius and sternocleidomastoid muscles?

They are named for their function or structure; for example, the trigeminal nerve consists of three primary branches, while the vestibulocochlear nerve serves the organs of equilibrium and hearing. and grab your free ultimate anatomy study guide! [1] The cranial component rapidly joins the vagus nerve, and there is ongoing debate about whether the cranial part should be considered part of the accessory nerve proper. On average, around four rootlets usually arise from this area, measuring roughly 17 mm in length. Laura Jean Shipley MD, in Pediatric Clinical Advisor (Second Edition), 2007, Tight SCM muscle, often with palpable, hard, olivelike mass in the midsection of the cervical muscle, Typically regresses by 4 to 6 months, leaving only contracture and fibrotic thickening of the involved muscle, Head tilt in the direction of the muscle involved with chin turned away from the contracted side, Later findings include facial asymmetry and plagiocephaly (flattening on affected side), Assess for other orthopedic abnormalities that may be associated with torticollis (e.g., congenital hip dysplasia), Assess for associated ophthalmologic and neurologic abnormalities, In Pediatric Clinical Advisor (Second Edition), 2007. Rotation, retraction, elevation, and depression of scapula, serratus anterior muscle, Latissimus dorsi, Pectoralis Major. They write new content and verify and edit content received from contributors. Dysarthria can be clinically categorized into spastic, cerebellar, extrapyramidal or lower motor neurone in type. The actions of the trapezius muscle is largely dependent on the direction of the fibres that are contracting. Variation of innervation pattern to the sternocleidomastoid muscle. The ACH causes the resting potential to increase above -55mV, thus initiating an action potential which travels along the muscle fiber. The cookies is used to store the user consent for the cookies in the category "Necessary". For cosmetic reasons, we use a small (2-3cm) skin incision along the posterior border of the SCM. In most cases Physiopedia articles are a secondary source and so should not be used as references. If you do not agree to the foregoing terms and conditions, you should not enter this site. As it moves caudally, it is medially related to the stylohyoid and digastric muscles, as well as the styloid process. The internal carotid artery to reach both the sternocleidomastoid muscles and the trapezius. Cranial Nerves Trochlear nerve: Ability to move your eyes up and down or back and forth. Post-radiation therapy has also been identified as a cause for isolated CN XI injuries as well. Sternocleidomastoid Muscle What is the closest relative to a hamster? When one side acts alone, it causes the head to rotate to the opposite side and flexes laterally to the same side (ipsilaterally). The trapezius muscles attach to several bones, including the spine, scapulae (shoulder blades), ribs and clavicle (collarbone). Which cranial nerve controls the trapezius and sternocleidomastoid muscles? The fibres from the cranial part are then distributed through the vagus nerve. What are the jumps called in show jumping? The sternocleidomastoid muscles are responsible for turning the head while the trapezius muscles control the action of Within the foramen, the spinal accessory nerve is laterally related to the vagus nerve. [7] Weakness in head-turning suggests injury to the contralateral spinal accessory nerve: a weak leftward turn is indicative of a weak right sternocleidomastoid muscle (and thus right spinal accessory nerve injury), while a weak rightward turn is indicative of a weak left sternocleidomastoid muscle (and thus left spinal accessory nerve). In addition, the trapezius is also involved in the movements of the head and neck. [5] Outcomes with surgical treatment appear to be better than conservative management, which entails physiotherapy and pain relief. What causes muscle spasms in the trapezius? The parts of the trapezius include: Along with latissimus dorsi, the trapezius is the most superficial of the superficial extrinsic back muscles. Cranial nerve Cranial Nerves This cookie is set by GDPR Cookie Consent plugin. when a weight is being carried in the hand. Linea nuchalis superior ossis occipitalis. [5], Injury to the accessory nerve can result in neck pain and weakness of the trapezius muscle. [9] Because diagnosis is difficult, electromyogram or nerve conduction studies may be needed to confirm a suspected injury. Schematic 3D model of the cranial nerves The hypoglossal nerve (XII) exits the skull using the hypoglossal canal in the occipital bone . Its main advantage is its regional proximity to the areas being reconstructed. The spinal accessory nerve then leaves the posterior border of the sternocleidomastoid to enter the posterior triangle of the neck. It also allows retraction, elevation, and rotation of the scapula. [13] This is in line with the observation that the spinal accessory nucleus appears to be continuous with the nucleus ambiguus of the medulla. [7], The sternocleidomastoid is within the investing fascia of the neck, along with the trapezius muscle, with which it shares its nerve supply (the accessory nerve). We stimulate the tissue along the posterior border of the SCM to confirm that there are no more nerve supplies to the SCM. To learn more on the ways that nerves heal after injury watch the great 8 minutes video clip below, Get Top Tips Tuesday and The Latest Physiopedia updates, The content on or accessible through Physiopedia is for informational purposes only. Anatomy and human movement: Structure and function. For completion, the other two columns form the nucleus of the hypoglossal nerve(general somatic efferent; CN XII) medially, and the special somatic efferent nuclei that innervate the derivatives of the derivatives of the pharyngeal arches. The spinal part supplies innervation to the Sternocleidomastoid and Trapezius muscles.[2]. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc. The fibres of the spinal accessory nerve originate solely in neurons situated in the upper spinal cord, from where the spinal cord begins at the junction with the medulla oblongata, to the level of about C6. All content published on Kenhub is reviewed by medical and anatomy experts. Together with the descending part, the ascending fibers also produce a rotation of the scapula around an axis which runs anteroposteriorly through the base of the scapular spine. [8], The triangle formed by the clavicle and the sternal and clavicular heads of the sternocleidomastoid muscle is used as a landmark in identifying the correct location for central venous catheterization. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. Language links are at the top of the page across from the title. Fig 1 Extracranial course of the accessory nerve. Reviewer: This portion of the nucleus ambiguus is referred to as the cranial nucleus of the accessory nerve. This test, coupled with the functionality test for sternocleidomastoid muscle, can be used to assess damage of the accessory nerve. Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. Trapezius muscle the XI nerve The muscles innervated directly by the XI nerve are the trapezius and the sternocleidomastoid, in addition to the laryngeal musculature (in collaboration with the vagus nerve), such as the palatal, pharyngeal, laryngeal muscles. It carries motor innervation to the pharyngeal constrictors, larynx, and muscles of the soft palate (except tensor veli palatini). [10], Traditionally, the accessory nerve is described as having a small cranial component that descends from the medulla and briefly connects with the spinal accessory component before branching off of the nerve to join the vagus nerve. In the original Bertrands technique, the peripheral main trunk of the eleventh nerve is completely exposed by sectioning the SCM with a large skin incision along the direction of the eleventh nerve. Accessory Nerve Cranial Nerve 11 Nerve damage and repair. A thorough medical and objective history should be carried out to determine the reasons for damage and the extent of the damage. The function of this muscle is to rotate the head to the opposite side or obliquely rotate the head. Copyright 2023 ElegantQuestion.com | All rights reserved. Sternocleidomastoid pain symptoms You may experience pain in your sinuses, forehead, or near your eyebrows. The fibers from the accessory nerve nucleus travel upward to enter the cranium via the foramen magnum. The patient presents with the head being turned toward the side of the lesion and away from the paralyzed side of the body. This assesses the power of the trapezius muscles. The trapezius muscle has several origin points along the midline of the posterior neck and back. The Accessory Nerve It is based either superiorly on the occipital and posterior auricular arteries or inferiorly on a branch of the thyrocervical trunk. The sternocleidomastoid provides excellent carotid coverage, but it is often resected during neck dissection, and it is therefore rarely used in head and neck oncologic surgery. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. Register now accessory_nerve Because there is another musclethe platysmabetween the sternocleidomastoid and the overlying skin island, it is theoretically unlikely that the sternocleidomastoid perforators would be the major blood supply to this skin, and clinical experience has confirmed this. Causes of damage may include trauma, surgery, tumours, and compression at the jugular foramen. The rootlets eventually coalesce to form a solitary nerve fiber known as the spinal accessory nerve. Because the function of the muscle is to flex and rotate the head to the opposite side, it is difficult to test in the newborn, especially in the premature infant. Author: This allows us to raise our arm above our heads beyond the level of the shoulder. It is often ipsilateral to the lesion and may radiate along the upper back and neck. The fibers merge together in the olfactory bulb, which is located above your nose. It is classified as the eleventh of twelve pairs of cranial nerves because part of it was formerly believed to originate in the brain. With a fine monopolar stimulation (1-5V, 5Hz, 0.2-0.5ms), the location of the eleventh nerve trunk is roughly confirmed by strong contractions of the trapezius muscle. What happens if cranial nerve 11 is damaged? Accessory Nerve Gray's Anatomy: The anatomical basis of clinical practice (41tst ed.). Traditionally, the accessory nerve is divided into spinal and cranial parts. Consequently, the nerve is commonly discussed according to the two divisions (i.e. [9] The nerve is intentionally removed in "radical" neck dissections, which are attempts at exploring the neck surgically for the presence and extent of cancer. Bilateral contraction of the descending part of trapezius (i.e. [2], Contributes to the supplying of the soft palate, larynx and pharynx muscles ( with larger contributions from cranial nerves 9 and 10 ), As the Trapezius and sternocleidomastoid muscles are derived from the pharyngeal arches some believe they must carry special visceral efferent information and other argue that they must contain general somatic efferent information.[1]. V1 (ophthalmic nerve) is located in the superior orbital fissure Therefore, the end organ motor may not be severely affected by unilateral upper motor neuron lesions. Make the changes yourself here! two components). Along their course, all fibers of the trapezius converge laterally on the superior angle of the scapula to attach on their respective insertion points. [4] Injury can cause wasting of the shoulder muscles, winging of the scapula, and weakness of shoulder abduction and external rotation.[5]. The upper fibers can elevate and upwardly rotate the scapula and extend the neck. The upper fibers can elevate and upwardly rotate the scapula and extend the neck. The jugular bulb also passes through this part of the foramen as well. 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 fibers located at the clavicle. Function of the sternocleidomastoid muscle is mediated by cranial nerve XI. At this very early period it is innervated by the nervus accessorius (CN XI in the adult form), and as the muscle mass moves into its adult position, it extends and moves caudally, carrying the nerve with it. The sternocleidomastoid muscle tilts and rotates the head, while the trapezius muscle, connecting to the scapula, acts to shrug the shoulder. We use cookies to help provide and enhance our service and tailor content and ads. As the trapezius muscle has an extensive vascular supply, it can be used as a site for musculocutaneous tissue flap harvesting for reconstructive purposes in other areas of the body, such as for breast reconstruction. You also have the option to opt-out of these cookies. Grounded on academic literature and research, validated by experts, and trusted by more than 2 million users. Contraction or contracture of the muscles of the neck causes the head to be tilted to one side. This is directed at restoring function to the shoulder girdle with emphasis on sternocleidomastoid and trapezius muscle. One useful maneuver with the full-term infant is to gently extend the head over the side of the bed with the child in the supine position. Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. What would happen if there were nerve damage to the sternocleidomastoid? From: Handbook of Clinical Neurology, 2012, Takaomi Taira, in Nerves and Nerve Injuries, 2015. Radiation therapy to the lymph nodes in the neck, Fracture of the atlas bone or hyoid due to direct trauma. The accessory nerve (cranial nerve XI) controls the sternocleidomastoid and trapezius muscles of the shoulder and neck. The function of the trapezius muscle can be tested by placing a hand on the patients shoulder and assessing their ability to elevate or shrug the shoulder against resistance. The trapezius muscle is the only muscle of the upper limb that does not receive its innervation from the brachial plexus. In this article, the anatomical course, motor functions and clinical relevance of the nerve will be examined. In higher vertebrates (reptiles, birds, mammals) there are 12 pairs of cranial nerves: olfactory (CN I), optic (CN II), oculomotor (CN III), trochlear (CN IV), trigeminal (CN V), abducent (or abducens; CN VI), facial (CN VII), vestibulocochlear (CN VIII), glossopharyngeal (CN IX), vagus (CN X), accessory (CN XI), and hypoglossal (CN XII). The spinal portion arises from neurones of the upper spinal cord, specifically C1-C5/C6 spinal nerve roots. The nerve has an intracranial course, a brief passage through a foramen, and an extracranial course. However, it is more common to observe the nerve passing anterolaterally with respect to the internal jugular vein. These are raised parts of the muscle that can be painful. It has a purely somatic motor function, innervating the sternocleidomastoid and trapezius muscles. damage to this nerve impairs vision. Congenital torticollis can have an unknown cause or result from birth trauma that gives rise to a mass or tumor that can be palpated within the muscle. As the spinal accessory nerve leaves the jugular foramen to enter the posterior triangle of the neck, it has a variable relationship to the internal jugular vein. The signaling process to contract or relax the sternocleidomastoid begins in Cranial Nerve XI, the accessory nerve. The formed nerve enters the skull through the foramen magnum, the large opening at the skull's base. Philadelphia, PA: Lippincott Williams & Wilkins. Oxford, England (6th edition): Churchill Livingstone. [17], English anatomist Thomas Willis in 1664 first described the accessory nerve, choosing to use "accessory" (described in Latin as nervus accessorius) meaning in association with the vagus nerve. The cranial part , along with the cranial nerves 9 and 10, supplies innervation to the soft palate, larynx and pharynx. Trapezius: ask the patient to shrug the shoulders. It leaves the cranium via the jugular foramen, where it briefly contacts the spinal part of the accessory nerve. The arterial supply to trapezius varies depending on the level. Anatomy, Head and Neck, Scalenus Muscle - StatPearls - NCBI Bookshelf. The pars nervosa is the smaller than the pars vascularis, located anteriorly toward the medial aspect of the foramen. The accessory nerve enervates the sternocleidomastoid muscles and the trapezius muscles. Sternocleidomastoid muscle Transmits visual signals from the retina of the eye to the brain. The cranial nerves also control balance, hearing, and swallowing. Syringomyelia, brainstem tumors, or infarctions can give rise to these lesions. [3], Strength testing of these muscles can be measured during a neurological examination to assess function of the spinal accessory nerve. The main function of the trapezius is stabilizing the scapula in its anatomical place, as well as controlling it during movements of the shoulder and upper limb. [8], In the neck, the accessory nerve crosses the internal jugular vein around the level of the posterior belly of digastric muscle, in front of the vein in about 80% of people, and behind it in about 20%,[8] and in one reported case, piercing the vein. Accessory nerve: want to learn more about it? Edinburgh: Elsevier Churchill Livingstone. Necessary cookies are absolutely essential for the website to function properly. Read more. It briefly meets the cranial portion of the accessory nerve, before exiting the skull (along with the glossopharyngeal and vagus nerves). Most texts will still refer to the accessory nerve as having two components. The contralateral paralysis of trapezius and ipsilateral paralysis of the sternocleidomastoid are associated with a unilateral cortical infarct. The accessory nerve nucleus is in the anterior horn of the spinal cord around C1-C3, where lower motor neuron fibers mark its origin. Dissection should be carried out until the eleventh nerve trunk is identified. The nucleus ambiguus is a large motor neuron that is embedded in the reticular formation. The sternocleidomastoid muscle has been used with an overlying skin paddle for oral cavity and pharyngeal reconstruction. WebWhich cranial nerve innervates the trapezius and sternocleidomastoid? V3 (mandibular nerve) is located in the foramen ovale. This point should be marked before introduction of anesthesia when the patient is still in a supine position. It is classified as the eleventh of twelve pairs of cranial nerves because part of it was formerly believed to originate in the brain. Surgical options comprise nerve surgery, nerve grafting, and nerve regeneration. This category only includes cookies that ensures basic functionalities and security features of the website. cranial and spinal roots). By visiting this site you agree to the foregoing terms and conditions. The corticobulbar fibers to the trapezius are crossed, and thus one cerebral hemisphere supplies the contralateral trapezius muscle. Try a cervical pillow. t e 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. By continuing you agree to the use of cookies. Cranial nerves It is a paired structure (with one on either side of the skull) that is limited posteromedially by the occipital boneand anterolaterally by the temporal bone. Available from: The Audiopedia. Revise the location of the 12 cranial nerves with the following quiz. Fig 2 Lateral view of the neck. and grab your free ultimate anatomy study guide! Nerve Test the other sternocleidomastoid by reversing the test. More rarely, the adjoining margins of the sternocleidomastoid and trapezius are in contact. Attempts are made to spare it in other forms of less aggressive dissection. Analytical cookies are used to understand how visitors interact with the website. While every effort has been made to follow citation style rules, there may be some discrepancies. Caution: Carotid artery. Torticollis gives the appearance of a tilted head on the side involved. These fibres coalesce to form the spinal part of the accessory nerve, which then runs superiorly to enter the cranial cavity viathe foramen magnum. It innervates both the trapezius and the sternocleidomastoid muscles. Further points regarding lesions of the accessory nerve will also be included here. Learning anatomy is a massive undertaking, and we're here to help you pass with flying colours. Get rid of shoulder and scapular pain by flossing. The trapezius is largely involved in movements of the shoulder girdle, and is therefore functionally considered as a muscle of the upper limb rather than of the back . 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 fibers located at the clavicle. Seldom there are isolated lesions of the accessory nerve. 2023 In addition, the trapezius covers several muscles of the superficial layer of the intrinsic muscle group, such as the splenius capitis, splenius cervicis, spinalis, longissimus and iliocostalis muscles. This means that the sternocleidomastoid is controlled by the brain on the same side of the body. The theoretic possibility of transplanting neck metastases is another concern. [caption id="attachment_9762" align="aligncenter" width="596"], [caption id="attachment_9763" align="aligncenter" width="457"]. Grounded on academic literature and research, validated by experts, and trusted by more than 2 million users. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. What nerve runs through the trapezius muscle? Treasure Island (FL): StatPearls Publishing; 2019 Jan-. This cookie is set by GDPR Cookie Consent plugin. Found an error? The sternal head is a round fasciculus, tendinous in front, fleshy behind, arising from the upper part of the front of the manubrium sterni. However, you may visit "Cookie Settings" to provide a controlled consent. 3 Which cranial nerves affect swallowing? What is the antagonist muscle to the trapezius? This nerve actually originates in the upper cervical spine but ascends into the cranium before descending back to its muscular connections, thereby making either cervical or intracranial sites locations for lesions that might result in weakness. Physiopedia is not a substitute for professional advice or expert medical services from a qualified healthcare provider. Lesions of the accessory nerve can be classified according to where along the course of the nerve the injury arises. This cluster of neurons, called the spinal accessory nucleus, is located in the lateral aspect of the anterior horn of the spinal cord, and stretches from where the spinal cord begins (at the junction with the medulla) through to the level of about C6. The cranial portion is much smaller and arises from the lateral aspect of the medulla oblongata. The supraclavicularis muscle arises from the manubrium behind the sternocleidomastoid and passes behind the sternocleidomastoid to the upper surface of the clavicle. A cranial nerve (a nerve that originates from the brain) controls the trapezius. [1] The cranial part , along with the cranial nerves 9 and 10, supplies innervation to the soft palate, larynx and pharynx. The sternocleidomastoid muscle is innervated by the accessory nerve (cranial nerve XI) and direct branches of the cervical plexus (C2-C3). Brian Abelson. 5 How does the cranial nerve innervate the trapezius? The patient's upper extremities should be otherwise relaxed. It then travels along the posterior edge of the sternocleidomastoid and then travels posteroinferiorly across the posterior triangle. XII Hypoglossal: Mainly motor Medulla: Located in the hypoglossal canal. The patient's upper extremities should be otherwise relaxed. Root [edit | edit source] The spinal part on the SAN arises from C1- You need our trunk wall muscle anatomy chart! "5. The accessory nerve (Fig. Cranial Portion: travels from medulla up to jugular foramen to exit and join the vagus nerve on its way to supply the soft palate, larynx and pharynx. It then separates into ventral and dorsal thickened areas known as basal and alar plates. However, there may be drooping of the affected shoulder as the muscle is no longer able to passively elevate the shoulder. Interrelationship of the Spine, Rib Cage, and Shoulder", "28. Match the names of the cranial nerves with their functions. In this article, we will discuss the detailed anatomy and function of the trapezius muscle. An operative microscope is essential to find fine branches to the SCM and to preserve the eleventh main trunk. Let us know if you have suggestions to improve this article (requires login). Get instant access to this gallery, plus: Introduction to the musculoskeletal system, Nerves, vessels and lymphatics of the abdomen, Nerves, vessels and lymphatics of the pelvis, Infratemporal region and pterygopalatine fossa, Meninges, ventricular system and subarachnoid space. The upper part of the trapezius also overlies the suboccipital region. The fibers arising from the intracranial component is known as the cranial accessory nerve, while those fibers arising from the spinal nucleus are called the spinal accessory nerve. [3], Course and distribution of the glossopharyngeal, vagus, and accessory nerves. Once you've finished editing, click 'Submit for Review', and your changes will be reviewed by our team before publishing on the site. Reading time: 10 minutes. Function Lateral flexion of neck There are usually 3 to 4 branches from the main trunk to the SCM. Palastanga, N., Field, D., & Soames, R. (1989). This nerve controls neck and shoulder movement and works with the sternocleidomastoid and trapezius muscles. [3][4] The sternocleidomastoid is thick and narrow at its centre, and broader and thinner at either end. The sternocleidomastoid muscle tilts and rotates the head, while the trapezius muscle, connecting to the scapula, acts to shrug the shoulder. Spinal Portion: Travels upwards as the C1-C5/6 spinal root section join together and exit out the jugular foramen, with the cranial portion. The middle fibers adduct (retract) the scapula. Language links are at the top of the page across from the title. Benign fibrosis of sternocleidomastoid (SCM) muscle, Most common cervical mass of infancy: Postulated to be muscular response to birth trauma or peripartum injury, Often diagnosed clinically without imaging, Ultrasound modality of choice when imaging required, Process entirely intramuscular (contained within SCM), without local invasion or inflammatory changes, Thick & short compared to contralateral SCM, Variable heterogeneity of lesion with loss of normal muscle architecture, Ranges from nearly homogeneous to markedly heterogeneous on US/CECT/MR, Variable internal vascularity within/about mass, No associated adenopathy or fluid collection, Contralateral occipital flattening (plagiocephaly), Treatment: Self-limited, usually resolves by 6 months of age, 90% fully recover with conservative treatment & physiotherapy, Surgery only in unusual cases when craniofacial asymmetry or refractory torticollis persists after 1 year, Jean-Pierre Barral, Alain Croibier, in Manual Therapy for the Cranial Nerves, 2009.