CERVICAL PLEXUS [plexus cervicalis (PNA, JNA, BNA)] —
the pair part of a peripheral nervous system formed by connection of front branches of the first four cervical spinal nerves near their escaping of intervertebral foramens.
Highway of page is located in front from an average scalene (m. scalenus med.) and the muscle raising a shovel (m. levator scapulae) under an upper part of a grudino-klyuchich-but-mastoidal muscle (tsvetn. tab., Art. 176, fig. 6). Motive branches of Sh. of page innervate nek-ry muscles of a neck (see below) and a diaphragm, and sensitive — skin of occipital area of the head, an auricle, a front and side surface of a neck, partially upper part of a breast.
Sh.'s nerves of page anastomose with a hypoglossal nerve (see), forming at the same time a cervical loop (ansa cervicalis), with an eleventh cranial nerve (see), a facial nerve (see), with a brachial plexus (see) by means of a non-constant anastomosis with the 5th cervical spinal nerve, and also with an upper cervical node of a sympathetic trunk.
The largest nerve of Sh. of page is the phrenic nerve (n. phrenicus). Usually it is formed by two roots, coming from Ssh and the additional root from Cv is available CIV, less often. In addition to motive and proprioceptive sensitive fibers pass in a phrenic nerve as well sensitive fibers, the innervating pericardium and partly a pleura and a peritoneum. The phrenic nerve on a neck goes down on a front surface of a front scalene (m. scalenus ant.), passes between a subclavial artery and the vein of the same name, then gets into a chest cavity. Further it follows together with a perikardodiafragmalny artery (a. pericardiacophrenica) and the vein of the same name on a side surface of a mediastinal pleura, passes ahead of a root of a lung and reaches a diaphragm near its tendinous center. The right phrenic nerve is shorter than left and passes from top to down more rectilinearly. The left nerve passes in front from an aortic arch and, going down to a diaphragm, bends around heart at the left. The branches of a phrenic nerve going to the peritoneum covering a diaphragm have bonds with branches of a celiac texture (see the Autonomic nervous system). Especially often the right phrenic nerve has such bonds, than irradiation of pain to the area of a neck at diseases of a liver speaks (see Frenika with - a symptom).
Short muscular branches of Sh. of page depart to long muscles of the head and a neck, front and lateral direct muscles of the head, front, average and back scalenes, the muscle raising a shovel (mm. longi colli et capitis, recti capitis ant. et lat., scaleni ant., med. et post., levator scapulae); quite often they depart directly from front branches of spinal nerves. Branches, the innervating muscles located below a hypoglossal bone (subhypoglossal muscles,
T.) — grudinopodjyazychny, grudinoshchitovidny, shchitopodjyazychny, scapular and hypoglossal, and also geniohypoid (mm. sternohyoideus, sternothyreoideus, thyreohyoideus, omohyoideus, genio-hyoideus), depart from the cervical loop formed upper koreshkokhm, going from a hypoglossal nerve (contains the fibers from the 1st and 2nd cervical spinal nerves getting into its structure on an anastomosis), and the lower root containing fibers from the 2nd and 3rd cervical spinal nerves.
Highway of page has sensitive branches, to-rye leave from under the rear edge grudino - a clavicular and mastoidal muscle approximately in the middle of it. The main sensory nerves of Sh. of page are the small occipital nerve, a big ear nerve, a cross nerve of a neck and supraclavicular nerves (3 — 5 nerves). The small occipital nerve (n. occipitalis minor) is formed by fibers of the 1st and 2nd cervical spinal nerves, climbs the rear edge grudino - a clavicular and mastoidal muscle and branches in skin of occipital area and partially an auricle. The big ear nerve (n. auricularis magnus) is formed by fibers of the 2nd and 3rd cervical spinal nerves, goes on an outer surface of the same muscle and branches in skin of an auricle and the inferiolateral surface of a face. The cross nerve of a neck (n. transversus colli) includes fibers from the 2nd and 3rd cervical spinal nerves, leaves from under the rear edge grudino - a clavicular and mastoidal muscle, goes forward and is divided into a number of the branches innervating skin of front department of a neck, its upper branch connects to a cervical branch of a facial nerve (ramus colli n. facialis). Supraclavicular nerves (nn. supraclaviculares) are formed by fibers of the 3rd and 4th cervical spinal nerves, go down to a clavicle, fanlikely branch and innervate skin of lower parts of a neck, and also the skin covering a deltoid muscle and anterosuperior department of a breast (to the II—III level of an edge).
Sh.'s defeats by the village happen unilateral and bilateral, and separate nerves, than all texture are surprised more often. Sh.'s pathology of page and its branches can arise at injuries (wounds of a neck, a birth trauma, etc.), inflammatory processes and surrounding tissues of a neck (see Shay), at infections or intoxications, at kraniovertebralny anomalies and tumors, coming from various formations of a neck and nearby bodies and fabrics, at metastasises of malignant tumors in deep limf, nodes of a neck, aneurisms of large vessels of a neck Observe also Sh.'s defeats by the village at radiation therapy of malignant lymphoma of a neck or radiation of metastasises of a malignant tumor in cervical limf. nodes. For development of pathology of Sh. of page and its branches the physical overstrain, the sharp movements or long stay in an inconvenient pose (static or dynamic loads), local and general cooling
, etc. can be provocative factors.
Defeat of branches of Sh. of page is shown by paralyzes, disturbances of sensitivity of skin in zones of an innervation of these branches, is more rare spasms of deep muscles of a neck. At paralysis of the muscles innervated by Sh. page, the head of the patient is inclined forward and it cannot lift it up. Spasms of the affected muscles are observed seldom. The unilateral tonic myotonia causes a picture of a wryneck (see), clonic — twitchings of the head to the opposite side, sometimes with simultaneous lifting of a shoulder; the bilateral clonic spasm leads to the nodding movements of the head (see Spasms, Thicke). Disturbance of sensitivity at irritation of nerves of Sh. of page has the nature of neuralgia (see), at deeper defeat the hypesthesia in a zone of an innervation of the struck Sh.'s branch of page develops. Damage of a small occipital nerve causes severe pains and a hyperesthesia of skin (is more rare a hypesthesia) in occipital area and partially skin of an auricle, morbidity at a palpation in points of an exit of a nerve on the rear edge of an upper third appears grudino - a clavicular and mastoidal muscle. At damage of a big ear nerve note disorders of sensitivity of skin (more rare than pain) in the field of a corner of a mandible and an auricle. At damage of supraclavicular nerves there are disturbances of sensitivity of skin in supraclavicular, subclavial, verkhnelopatochny areas and in verkhnenaruzhny department of a shoulder (skin over deltoid and big chest muscles). Damage of a phrenic nerve is more often observed in combination with damages and various patol. processes in adjacent bodies. At the same time can develop a phrenoplegia with an asthma, difficulty of tussive movements or (at irritation of a nerve) a hiccups (see) and the pains extending to the area of a shoulder girdle, a shoulder joint, neck and thorax.
Diagnosis of defeats of III. the page is based on the data of the anamnesis characteristic a wedge. manifestations (disturbance of movements and disorder of sensitivity) and careful inspection of bodies of a neck and chest cavity. For recognition of damage of a phrenic nerve the chest fluoroscopy matters, at a cut paradoxic movements and the unusual provision of a diaphragm on the party of defeat can be revealed; for recognition of neurogenic tumors of a neck an informative method of a research is the computer tomography.
394 CERVICOBRACHIAL SYNDROMES
Treatment of defeats of III. the page shall be directed to elimination of the reason which caused pathology and also to improvement of conductivity of nerve fibrils of a texture and stopping of a pain syndrome. Drug treatment is combined with physical therapy, LFK and massage (at an exception of pathology of Sh. of page caused by a malignant tumor). At the persistent hiccups caused by irritation of a phrenic nerve make a novocainic nerve block on a neck.
The forecast depends on character of the basic disease which caused Sh.'s pathology of page.
Bibliography: An intra barreled structure of peripheral nerves, under the editorship of. A. N. Mak-simenkova, L., 1963; The Multivolume guide to neurology, under the editorship of S. N. Da-videnkov, t. 3, book 1, page 99, M., 1962; About p e l I am a N with to and Ya. Yu. Vertebro-gennye's Y1 of a disease of a nervous system, t. 3, Kazan, 1981, bibliogr.; R and t of N e r A. Yu. and Soldatov L. P. Obstetric paralyzes at children, Kazan, 1975; Sinelnikov R. D. Atlas of anthropotomy, t. 3, page 24, M., 1981; A. V Triumphs. Topical diagnosis of diseases of a nervous system, L., 1974; Favorskii B. A. To a question of vnut-ristvolny very tectonics of a peripheral nervous system, Zhurn. neuropath, and psikhiat., t. 61, No. 2, page 305, 1961;
Clara M. Das Nervensystem des Men-schen, Lpz., 1959.
I. P. Antonov (pathology), V. I. Kozlov