From Big Medical Encyclopedia

SACRAL AREA [regio sacralis (PNA, JNA, BNA)] — the area of a body matching on extent a dorsal surface of a sacrum, border a cut from above pass across the line between the right and left lower lateral lumbar poles (at once below and medialny from an upper back ileal awn), from sides — across the lines going on medial edges of eminences of big gluteuses and agreeing on a tailbone at the beginning of a mezhjyagodichny furrow (fig. 1). To. the lake makes a part of a back wall of a small pelvis. In the middle To. the lake is probed a median sacral crest (crista sacralis mediana), sometimes a lateral sacral crest, on the upper bound — an acantha — L5. Sizes and form K. lakes depend on individual and sexual distinctions of a structure of a basin. At the people having a narrow basin (hl. obr. at men), To. the lake in a form approaches an isosceles triangle with the narrow basis, at people with a wide basin (hl. obr. at women) — to an equilateral triangle.

Fig. 1. Borders of sacral area (are designated by the black line).
Fig. 2. Muscles of sacral area (back view): 1 — a cross and awned muscle; 2 — a big gluteus; 3 — an iliocostal muscle of a waist; 4 — the longest muscle of a breast; 5 — an internal oblique muscle of a stomach.
Fig. 3. Dorsal surface of a sacrum (linking of a sacrum): 1 — an acantha Y lumbar vertebras; 2 — an iliolumbar sheaf; 3 — an upper back ileal awn; 4 — a big sciatic opening; 5 — a long dorsal sacroiliac sheaf; 6 — a sacral and hilly sheaf; 7 — a sacral and awned sheaf; 8 — a small sciatic opening; 9 — a tailbone; 10 — a superficial dorsal sacrococcygeal sheaf; 11 — dorsal sacral openings; 12 — short dorsal sacroiliac sheaves.
Fig. 4. Pelvic surface of a sacrum (linking of a sacrum): 1 — iliolumbar sheaves; 2 — ventral sacroiliac sheaves; 3 — a big sciatic opening; 4 — a kresttsovoostisty sheaf; 5 — sacral bugornaya a sheaf; 6 — a ventral sacrococcygeal sheaf; 7 — a front longitudinal sheaf; 8 — pelvic sacral openings; 9 — the cape of a sacrum.
Fig. 1. Sacral area, the sacral channel (back view) is opened: 7 — a „horse" tail; 2 — upper nerves of buttocks; 3 — a firm cover of a spinal cord; 4 — average nerves of buttocks; 5 — poyasnichno - a sternal fascia; 6 — a big gluteus; 7 — thread of a firm cover of a spinal cord; 8 — back branches of sacral nerves; 9 — the section of arches of sacral vertebrae; 10 — an internal vertebral veniplex; 11 — a front branch of a sacral spinal nerve; 12 — a spinal node.
Fig. 2. Anatomic formations of a pelvic surface of a sacrum (anterior aspect): 1 — the lower vena cava; 2 — a ventral aorta; 3 — the big lumbar muscle (is dissected away); 4 — a square muscle of a waist; 5 — a cross muscle of a stomach; 6 — a podvzdoshnopakhovy nerve; 7 — a genitocrural nerve; lateral cutaneous nerve of a hip; 9 — an ileal muscle; 10 — a median sacral vein; 11 — a median sacral artery; 12 — a locking nerve; 13 — a lumbosacral trunk; 14 — sacral nodes of a sympathetic trunk; 15 — a sacriplex; 16 — a femoral nerve; 17 — a coccygeal muscle; 18 — an internal locking muscle; 19 — a rectum; 20 — an unpaired coccygeal node; 21 — a pubic bone (the pubic symphysis is removed); 22 — the right yaichkovy arteries and veins; 23 — the right outside ileal artery; 24 — the right internal ileal vein; 25 — the right outside ileal vein; 26 — the right lateral sacral artery and a vein; 27 — the right internal ileal artery; 28 — the right general ileal artery; 29 — the right general ileal vein.

Skin To. the island dense, is more fat, than on side surfaces of a trunk, moderately mobile, contains a large number of sweat and sebaceous glands. Hypodermic cellulose and a superficial fascia are expressed poorly. In hypodermic cellulose the network of superficial veins (sources of lateral sacral veins), skin branchings of lateral sacral arteries, average nerves of buttocks are located (nn. clunium medii). Behind the most acting part of a median sacral crest the small hypodermic bag (bursa subcutanea sacralis) sometimes meets. More deeply the superficial leaf of a thoracolumbar fascia (f. thoracolumbalis) forming a back wall of a vagina of the muscle straightening a backbone (m. erector spinae) is located. Under this leaf of a fascia the fibers of the muscle straightening a backbone, originating from a back surface of a sacrum lie: lateral and lumbar iliocostal (m. iliocostalis lumborum) and a medial and initial part of the longest muscle of a breast (m. longissimus thoracis) — fig. 2. Under them are visible a sacral part of a cross and awned muscle (m. trarisversospinalis), and below and in the middle — a dorsal sacrococcygeal muscle (m. sacrococcygea dorsalis) and a superficial dorsal sacrococcygeal sheaf, the cut is deeper there is a deep dorsal sacrococcygeal sheaf, and lateralno — short and long dorsal sacroiliac, sacral and awned and sacral bugornaya sheaves (fig. 3). After removal of muscles the back branches of sacral nerves and a lateral sacral artery and a vein going through dorsal sacral openings are visible. In the sacral channel which is continuation of the vertebral channel Epidural cellulose very friable also has big ability to absorption. In it the veniplex connecting above to an internal vertebral veniplex, and lateralno — with veins of a sacrum and a basin lies. Therefore the epidural veniplex is the collateral way connecting systems top and bottom venas cava. Bonds of a texture with veins of a basin serve by distribution patol, processes (in particular, tumor cells) from a basin in other departments of a body. The firm cover of a spinal cord forms a covering of the channel to S3, and also for sacral roots of a spinal cord. In the bag formed by a firm cover of a spinal cord there is a terminal thread (filum terminale) of a spinal cord and the bottom of a horse tail (cauda equina — tsvetn. fig. 1). On a pelvic surface of a sacrum first of all the front longitudinal sheaf is defined (lig. longitudinale ant.), ventral and lateral sacrococcygeal sheaves (ligg. sacrococcygea ventrale et laterale), iliolumbar (lig. iliolumbale), ventral sacrolumbar, sacral and awned and sacral bugornaya sheaves (fig. 4). Knaruzhi pair pear-shaped muscles originate from pelvic sacral openings (mm. piriformes), and through openings there are in a basin front branches of sacral nerves. In the middle of a pelvic surface of a sacrum there pass a median sacral artery and a vein (and. et v. sacrales medianae), knaruzh from pelvic sacral openings — lateral sacral arteries and veins (aa. et vv. sacrales laterales), sacral department of a sympathetic trunk. Inflows of median and lateral sacral veins form a sacral veniplex (plexus venosus sacralis), an anastomozira yushchy with parietal veins of a basin (tsvetn. fig. 2). Further kpered there is a parietal layer of a pelvic fascia, for the Crimea in cellulose are located sacral limf, nodes, are slightly more left than the middle — upper pryamokishechny vessels, top and bottom hypogastric vegetative textures and a rectum.



Disturbances of complex process of embryonic development To. lakes are an origin any patol, processes here. Not fusion of handles (spina bifida sacralis) of separate sacral vertebrae occurs at 67% of all people (see S pina bifida ). Not fusion of handles in most cases is only option of development of a sacrum. Sometimes it is followed by cystous protrusion of a kzada of the end of a spinal cord (myelocele), its covers (meningocele) or their combinations. In a bag of such hernia of thread of a horse tail can freely go, but are sometimes spliced with its walls or even come to an end in them. Hernia of a spinal cord often is followed by sensitive and motive paralyzes.

From malformations of a bone skeleton unions of lumbosacral vertebrae — a sacralization of L5 or lumbalization of S1 are quite often observed (see. Sacralization , Lumbalization ), cross crevices, bone exostoses (see). Also lack of a sacrum and tailbone (agenesia) or their poor development (hypoplasias) meets. Important practical value has the narrowing of the sacral channel which is the reason of a prelum of a horse tail. From other malformations To. lakes meet dermoid and epithelial cysts, coccygeal funnels, the courses, etc.

In diagnosis of anomalies of development of a bone skeleton To. the lake has essential value rentgenol, a research. On direct back and side roentgenograms happens the union of L-of a vertebra with a sacrum or likening of St is well visible to a lumbar vertebra, not fusion of handles, narrowing of the sacral channel.

Operational treatment at malformations is applied restrictedly; among methods of conservative therapy use thermal procedures, to lay down. gymnastics, dignity. - hens. treatment, novocainic blockade, etc.


At bruises To. the lake can be observed accumulation of blood in hypodermic cellulose in the form of superficial, moderately painful fluctuating tumor. Bruises, anguishes and separations of muscles can lead to ossification of a part of muscles and periosteums on site damages that comes to light on roentgenograms in the form of sites of calcification.

Changes of a sacrum distalny sacroiliac joint (see) meet in 1 — 4% of cases of all changes of pelvic bones. They most often result from direct stroke, is more rare during the falling on buttocks. These changes can sometimes arise at a prelum of the victim in the perednezadny direction. The wedge, a picture of a change is characterized by emergence of a swelling, bruise, local morbidity in the place of a change at a palpation. At changes of a sacrum of the patient cannot stand. At a research through a rectum sometimes it is possible to feel the place of a change and to define degree of shift of fragments. Pressing on a tailbone causes sharp pain in the place of a change, can irradiate edges in the lower extremities and a rump. At this change damage of nervous roots at the time of an injury or their prelum in the subsequent can be observed by the formed bone callosity. Sometimes such changes proceed without considerable painful manifestations, and victims even come to the doctor on foot. On roentgenograms lines of changes are found.

Fire damages To. islands treat the heaviest injuries of bones of a skeleton. Buttonhole, multisplintered, zhelobovaty and regional fractures of a sacrum meet. Fragments and impressions of an outside plate in spongy substance of side masses are sometimes observed. At the same time the hurting shell can get stuck in the bone. These wounds often are followed by shock, considerable bleeding, and is later suppurative processes. V. D. Chaplin observed development of osteomyelitis at gunshot wounds of pelvic bones in 60 — 80%.

At bruises To. lakes apply analgetics, thermal procedures and if the hematoma (was formed especially at amotio of skin) — a puncture to evacuation of blood and a pressure compressing bandage.

At fractures of bones To. lakes produce intra pelvic anesthesia of 2% solution of novocaine. High bed rest on a board 3 — 4 weeks. It is allowed to sit 2 — 3 months later. Disability of 3 — 4 months


B K. lakes are observed inflammatory diseases of soft tissues (furuncles, an anthrax, phlegmons, a bursitis). Decubituses To. lakes often develop at the weakened patients at a long bed rest and lack of due leaving. At heavy patients transition is possible decubituses (see) in phlegmon (see) and as a complication — an erysipelatous inflammation. Epithelial cysts and fistulas To. the lake at ostrovospalitelny process (see. Tailbone ) in connection with inconstancy a wedge, pictures of a disease present difficulties for differential diagnosis with tubercular process, osteomyelitis and even a paraproctitis.

Inflammatory diseases of bones To. lakes meet as in the form of acute inf. osteomyelites, and chronic, is more often than tubercular.

Osteomyelites are observed after scarlet fever, measles, a sapropyra, after injuries. The disease develops quickly, the general state worsens, the fever and pains in the field of a sacrum appear, function of intestines is sometimes broken.

Tuberculosis affects average department of a sacrum — a sacroiliac joint. The disease proceeds in the beginning is latent; at this time there are slowly accruing pains, subfebrile condition, a febricula. Displays of a disease accrue during formation of congestive abscesses on a back surface of a sacrum. Fistular forms of tuberculosis of a sacrum are shown by a slow inflammation with scanty separated gray color. Lack of excess granulations, Tsianotichesky coloring of skin around a wound, intoxication is characteristic.

Development dense, motionless, with a clear boundary, low-painful infiltrate is characteristic of an actinomycosis of the coccygeal course. In the field of the fistular course the small knots which are slightly towering over the level of skin are palpated. From fistulas pus, sometimes with impurity of blood is emitted. Microscopic examination allows to find druses of a fungus of Actinomyces.

Syphilitic defeat To. the lake meets extremely seldom and is expressed in a gummous osteoperiostitis. Diagnosis is complicated because of scarcity a wedge, manifestations. Positive Wassermann reaction helps with diagnosis.

Conservative treatment is carried out only at inflammatory diseases of soft tissues to stages of formation of infiltrate. It is directed to increase in body resistance. At tuberculosis, syphilis, an actinomycosis specific treatment is applied. Tuberculosis and osteomyelitis quite often demand operational treatment.

Tumors are very various on the morfol, structure. From benign tumors in sacral area lipomas, fibromas are observed, hemangiomas (see), neurinoma (see), chondroma (see), chordomas, teratomas (see), osteoid osteomas, etc.

Benign tumors of a sacrum on roentgenograms are usually shown in the form of roundish or oval enlightenments with accurate outlines; on their background islands of calcification can sometimes come to light. From malignant tumors in To. lakes are described primary and secondary chondrosarcomas, reticulosarcomas, giant-cell tumors, the mixed malignant tumors, fibrosarcomas, osteosarcomas, Ewing's tumors, planocellular cancer and metastasises of cancer. Tumors, expanding in various directions, squeeze nervous roots, trunks and branches of a lumbar texture, cause pain of different intensity. Malignant tumors of a sacrum (Ewing's tumor, an osteosarcoma) give a picture of destruction without accurate otgranicheniye from not affected areas of a bone. Side roentgenograms allow to distinguish tumors of a sacrum from patol, the formations of a basin proyektsionno accumulating on a shadow of a sacrum in a direct projection. At benign tumors according to indications apply operation, the vast majority of malignant tumors demands the combined treatment — operational, beam, chemotherapeutic.


At operations on To. islands use both an inhalation anesthesia, and local anesthesia.

Complexity of an anatomic structure of a basin, existence of vitals in narrow anatomic area, abundance of blood vessels and nerves create considerable difficulties at the choice of quick access to these or those departments To. lake. The anomalies of development demanding plastic closing of defect (spina bifida sacralis), a sacrectomy at infringement of a horse tail or removal of a tailbone at hvostopodobny appendages of a tailbone and also opening of furuncles, anthrax, phlegmons and other diseases of soft tissues are the most available to operational treatment. Accesses at primary tumors and gunshot wounds are more difficult To. the lake, especially at the combined defeats and damages of pelvic bodies. After removal of wounded from state of shock primary surgical treatment of a wound is made, edges at the same time is the major preventive action in the prevention of complications a purulent infection. Access at the same time is provided through the place of wound. At emergence of profuse bleedings, in addition to a tamponade, quite often it is required to make bandaging of internal ileal arteries.

Scyphoid access across Knysh is preferable to removal of tumors of a small pelvis.

Bibliography: The multivolume guide to orthopedics and traumatology, under the editorship of N. P. Novachenko, t. 3, page 350, M., 1968; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 13, page 151, M., 1955; T r and p e z N and to about in H. N and r and about r about in and T. M. Primary tumors of pelvic bones, M., 1978, bibliogr.; H and to l and V.D's N. Fundamentals of operational orthopedics and traumatology, page 571, M., 1964; it, Tumours of bones and joints, M., 1974, bibliogr.; In u with le ni of 1 1 T. M and. In 1 and with k b u of n e J. S. Fraeture-dislocations of the sacrum, J. Bone Jt Surg., v. 58-B, p. 467, 1976; K o h 1 e r A. Z i m m e r E.A. .Grenzen des Normalen und Anfange des Pathologischen im Ront-genbild des Skelets, S. 365, Stuttgart, 1967; P e of n k o p f E. Topographische Anato-mie des Menschen, Bd 2, Hft 1, S. 233, B. — Wien, 1943.

A. H. Shabanov; A. H. Maksimenkov, S. S. Mikhaylov (An).