Ministry of Public Health of Ukraine Ukrainian Medical Stomatological Academy "Approved" at the meeting of the Department of Human Anatomy «29»08 2020 Minutes № Head of the Department Professor O.O. Sherstjuk ________________________ METHODICAL GUIDANCE for the lecture Academic subject Human Anatomy Module No 3 "The heart. Vessels and nerves of the head, the neck, the trunk, extremities" Lecture No 13 The peripheral nervous system. Spinal nerves. Somatic plexus. Cranial nerves. Year of study І Faculty Foreign students' training faculty, specialty «Medicine» Number of 2 academic hours Poltava – 2020 1. Educational basis of the topic The peripheral nervous system consists of the cranial and spinal nerves and their associated ganglia. There are 31 pairs of spinal nerves that leave the spinal cord and pass through intervertebral foramina in the vertebral column. Inflammatory processes, toxic lesions and injury sequelae are known under common term ‘neuritis’. The state manifests itself as painful sensation in the affected area (mostly in the lumbar and the sacral regions). 2. Learning objectives of the lecture: . to familiarize students with the divisions of the nervous system and structural functional unit of the nervous system; . to specify classification and functional significance of the spinal nerves; . to provide theoretical information on relations of the spinal nerves to the spinal segments; . discuss branches of spinal nerves with featured structural and topographical regularities. 3. Objectives of developing the future specialist’s personality (educational aims and objectives): familiarization with axiological, ethical and deontological principles of medical profession. 4. Interdisciplinary integration The preceding The acquired knowledge subjects Biology What are the main functions of the nervous system. The reflex arc and its variations. Histology Structure of nerve fibers. Neurology Topography of the nervous branches. Physics Describe the mechanism of nerve impulse. Anatomy Structure of the spinal cord, internal and external structures. 5. The plan and organization of lecture structure No The main stages of the lecture Type of lecture. Time and their content Means of motivation. allocation Teaching materials The preparatory stage 5% 1. Determining the relevance of the pp. 1-2 topic, learning objectives and motivation. The main stage Introductory lecture 85% 2. Delivering the lecture material according to the plan: Feedback and questions 1. Name the principal components to students of the peripheral nervous system and give their general PPT presentation with characteristics. diagrams and tables. 2. Describe formation, topography and branches of the spinal nerves. Explain relations of the spinal nerves to the spinal segments. 3. Describe contents, topography and responsibility areas of the posterior branches of spinal nerves. 4. Describe the anterior branches of the cervical plexus including contents, topography and responsibility areas. 5. Describe formation, branches, topography and responsibility areas of the intercostal nerves. 6.Describe formation, topography, parts and classification of branches of the brachial plexus. 7. Describe the femoral nerve. 8. Describe the obturator nerve. 9. Describe the pudendal nerve. 10. Describe the long branches of the sacral plexus. 11. Describe the sciatic nerve. 12. Describe the tibial nerve. 13. Describe the common fibular nerve. 14. Name all pairs of the cranial nerves. 15. Discuss classification of the cranial nerves by fibers contents. 16. Discuss classification of the cranial nerves by origin. 17. Describe origination, formation and topography of the cranial nerves. The final stage Human Anatomy. In 10% 3. General conclusions to the lecture. three volumes. Volume 3: Answers to possible questions. textbook / Edited by Tasks for students’ self-directed V.G. Koveshnikov. - work. Lugansk: LTD «Virtualnaya realnost», 2009. – 384p. 6.The lecture material. THE CERVICAL PLEXUS, PLEXUS CERVICALIS (Cl - C4) The cervical plexus arises from anterior branches of four upper cervical nerves (Cl — C4). It lies on the deep cervical muscles anterior to the transverse processes of cervical vertebrae, below the sternocleidomastoid. The plexus gives rise to the sensory, the motor and the mixed branches. The cutaneous (sensory) branches from under the posterior margin of the sternocleidomastoid: ■ the lesser occipital nerve, nervus occipitalis minor ascends to the skin of the occipital region; ■ the great auricular nerve, nervus auricularis magnus ascend along the sternocleidomastoid to the auricle and the external acoustic opening; ■ the transverse cervical nerve, nervus transversus colli runs transversely to the anterior and lateral cervical areas; ■ the supraclavicular nerves, nervi supraclaviculares descend to the upper thoracic regions and shoulder along the lateral cervical triangle. On the way to destination point, the nerves cross the clavicle. The ansa cervicalis is a purely motor branch. It is formed of the superior and the inferior roots. The superior root arises from the hypoglossal nerve yet it constitutes the motor fibers from the Cl. The inferior root arises from the cervical plexus (C2 — C3) and joins the superior root thus forming the ansa. It resides anterior to the internal jugular vein below the sternocleidomastoid. The ansa gives off some branches to the infrahyoid muscles (the sternohyoid, the sternothyroid, the thyrohyoid and the omohyoid). The muscular (motor) branches supply the deep cervical muscles like the longus colli, the longus capitis, the scaleni muscles, the rectus capitis anterior and the rectus capitis lateralis and the levator scapulae. The phrenic nerve, nervus phrenicus is the greatest nerve of the cervical plexus and the sole mixed-type nerve of the group. It runs downwards along the anterior scalene, musculuus sca-lenus anterior to reach the thoracic cavity. The right nerve enters the thoracic inlet between the subclavian artery and the subclavian vein and runs further on anterior to the root of lung between the respective pleura and the pericardium. The left nerve enters the thoracic inlet posterior to the subclavian vein along the subclavian artery. The nerve crosses the aortic arch and proceeds anteriorly and leftwards along the pericardium to reach the respective portion of the diaphragm. The motor branches terminate within the diaphragm to provide motor nerve supply to the muscle (C3 — C5). The phrenic nerve also comprises the sensory fibers to the pleura and the pericardium — the pericardial branch, ramus pericardiacus. The sensory phrenico- abdominal branches, rami phrenicoabdominales penetrate the diaphragm to supply the related peritoneum. The sensory branches of the right phrenic nerve traverse the coeliac plexus and reach the liver; they provide sensory nerve supply to the peritoneal investment and the fibrous capsule of liver. Fig. Cervical plexus. Clinical applications. Some liver diseases may result in painful sensations along the right phrenic nerve. The pain in this case expands onto the cervical region and concentrates between the crura of the sternocleidomastoid (thus providing easily distinguishable ‘phreni- cus-symptom’). The phrenic nerve is a vital nerve that sets the diaphragm to motion. The nuclei of the phrenic nerve reside within the anterior grey columns of the segments C3 through C6. Injury to the nuclei or to the nerves may result in diaphragm paralysis. Fig. Cervical plexus. THE BRACHIAL PLEXUS, PLEXUS BRACHIALIS (C5-C8 and Thl) The brachial plexus arises from anterior branches of four lower cervical nerves (C4 — C8) and greater portion of the anterior branch of the first thoracic nerve (Thl). The brachial plexus features the supraclavicular and the infraclavicular parts. 1) the supraclavicular part, pars supraclavicularis appears as three trunks that pass between the anterior and the middle scaleni muscles. The trunks are the superior trunk, truncus superior, the middle trunk, truncus medius and the inferior trunk, truncus inferior; 2) the infraclavicular part, pars infraclavicularis is the part situated within the axillary fossa where the trunks regroup into the cords, faciculi that surround the brachial artery. The cords are as follows: the lateral cord, fasciculus lateralis runs laterally along the artery; the medial cord, fasciculus medialis runs medially along the artery; the posterior cord, fasciculus posterior runs posteriorly along the artery. The branches of the supraclavicular part This part gives rise to the short branches related to the pectoral girdle; ■ the dorsal scapular nerve, nervus dorsalis scapulae runs to the levator scapulae and the rhomboid muscles; ■ the long thoracic nerve, nervus thoracicus longus supplies the neighboring serratus anterior; ■ the suprascapular nerve, nervus suprascapularis crosses the suprascapular notch and reaches supraspinous and infraspinous fossae. It supplies the respective muscles and the joint capsule of the shoulder joint; ■ the subclavian nerve, nervus subclavius supplies the muscle of the same name; ■ the lateral and medial pectoral nerves, nervi pectorales lateralis et medialis supply the pectoralis major and the pectoralis minor; ■ the subscapular nerve, nervus subscapularis supplies the subscapularis and the teres major, ■ the thoracodorsal nerve, nervus thoracodorsalis runs along the lateral border of scapula; it supplies the latissimus dorsi; • the axillary nerve, nervus axillaris is the greatest of the short branches. It arises from the posterior cord and proceeds