Diaphragm
Last reviewed: 23.04.2024
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Diaphragm (diaphragma, sm phrenicus) - a movable muscular-tendon septum between the thoracic and abdominal cavities. The diaphragm has a domed shape, due to the position of the internal organs and the difference in pressure in the thoracic and abdominal cavities. The convex side of the diaphragm is directed into the thoracic cavity, concave - down, into the abdominal cavity. The diaphragm is the main respiratory muscle and the most important organ of the abdominal press. The muscle bundles of the diaphragm are located on the periphery, have a tendon or muscle origin on the bone portion of the lower ribs or costal cartilages surrounding the lower aperture of the chest, on the posterior surface of the sternum and lumbar vertebrae. Coming to the top, toward the middle of the diaphragm, the muscle bundles pass to the tendon center (centrum tendineum). Accordingly, the beginning distinguish the lumbar, costal and sternal parts of the diaphragm. Muscular bundles of the lumbar part (pars lumbalis) of the diaphragm begin at the anterior surface of the lumbar vertebrae, forming the right and left legs (crus dextrum and crus snistrum), and also on the medial and lateral arcuate ligaments. The medial arched ligament (lig. Arcuatum mediale) is stretched over the large lumbar muscle between the lateral surface 1 of the lumbar vertebra and the apex of the transverse process II of the lumbar vertebra. The lateral arcuate ligament (lig. Arcuatum laterale) runs transversely in front along the square lower lumbar and connects the tip of the transverse process 11 of the lumbar vertebra with the XII rib.
The right leg of the lumbar part of the diaphragm is developed more strongly and begins on the front surface of the bodies of I-IV lumbar vertebrae. The left foot originates on the first three lumbar vertebrae. The right and left legs of the diaphragm are intertwined in the anterior longitudinal ligament of the spine. Above, the muscle bundles of these legs cross in front of the body of the I lumbar vertebra, restricting the aortic opening (hiatus aorticus). Through this aperture pass the aorta and the thoracic (lymphatic) duct. The edges of the aortic aperture of the diaphragm are limited by bundles of fibrous fibers - this is the middle arc-shaped ligament (lig. Arcuatum medianum). With the contraction of the muscle bundles of the diaphragm's legs, this ligament protects the aorta from compression. Above and to the left of the aortic opening, the muscle bundles of the right and left legs of the diaphragm re-cross, and then again diverge, forming the esophageal foramen (hidtus esophageus). Through this opening, the esophagus, together with the vagus nerves, passes from the thoracic cavity to the abdominal cavity. Between the muscle bundles of the right and left legs of the diaphragm pass the corresponding sympathetic trunk, the large and small celiac nerves, as well as the unpaired vein (right) and the semi- unpaired vein (left).
On each side between the lumbar and costal parts of the diaphragm is a triangular shape, devoid of muscle fibers, the so-called lumbar-rib triangle. Here the abdominal cavity is separated from the thoracic cavity only by thin plates of the intra-abdominal and intrathoracic fascia and serous membranes (peritoneum and pleura). Within this triangle, diaphragmatic hernias can form.
The anterior part (pars costalis) of the diaphragm begins on the inner surface of six or seven lower ribs by separate muscle bundles that wedge between the teeth of the transverse abdominal muscle.
The sternal part (pars sternalis) of the diaphragm is the narrowest and weakest, begins on the posterior surface of the sternum.
Between the sternum and the costal parts of the diaphragm there are also triangular patches - the sternocostal triangles , where, as noted, the thoracic fascia and abdominal cavity are separated from each other only by the intrathoracic and intra-abdominal fascia and serous membranes (pleura and peritoneum). Here, too, diaphragmatic hernias can form.
In the tendon center of the diaphragm on the right there is an opening of the inferior vena cavae (foramen venae cavae), through which this vein passes from the abdominal cavity to the thoracic vein.
Function of the diaphragm: when the diaphragm is contracted, its dome is flattened, which leads to an increase in the thoracic cavity and a decrease in the ventral cavity. With a simultaneous contraction with the abdominal muscles, the diaphragm helps increase intra-abdominal pressure.
The innervation of the diaphragm: diaphragmatic nerve (CIII-CV).
Diaphragm blood supply: upper and lower diaphragmatic arteries, posterior intercostal arteries (lower).
[Diseases of the diaphragm
Damage to the diaphragm can occur with penetrating wounds to the chest and abdomen and with closed trauma, mainly during transport or catatravel (falling from height). Against the background of this injury, diaphragm damages are not always determined clinically, but in all cases of chest and abdominal damage the diaphragm should be examined without fail, and it should be remembered that in 90-95% of cases of closed trauma the left dome is damaged.
The most common pathology of the diaphragm is a hernia. By localization, the hernia of the dome of the diaphragm and esophageal opening is distinguished. Very rarely there are hernia slits of the sympathetic trunk, inferior vena cava, the opening of the intercostal nerve, but they do not give the clinic and more often serve as an operational finding. By origin, hernias are divided into congenital and acquired, with a missed rupture. Clinical manifestations depend on the size of the hernial gates and tissues emerging through them into the thoracic cavity. With a small size and prolapse of only the epiploon of clinical manifestations of a hernia may not be. The most severely affected are the herniated dome of the diaphragm (hernia of the esophagus is never infringed): a sudden attack of sharp pains in the epigastrium and chest, may even be painful shock, palpitation, dyspnea, vomiting, with bowel obstruction, signs of intestinal obstruction.
Sliding herniation of the dome of the diaphragm, more often traumatic genesis, but can also form with the underdevelopment of the diaphragm with localization in the rib-lumbar triangle, usually on the left (hernia of Bogdalek), accompanied by two syndromes: gastrointestinal and cardio-respiratory or a combination of them. Gastrointestinal syndrome manifests itself in pain in epigastrium and hypochondrium (more often in the left), in the chest, giving up - to the neck, arm, under the scapula, emaciation, vomiting, sometimes with an admixture of blood, paradoxical dysphagia (freely passes solid food, azhidkaya is delayed, followed by vomiting ). When prolabirovanii in the chest cavity of the stomach can be gastric bleeding. Cardiorespiratory syndrome is manifested by cyanosis, dyspnea, palpitation, which is intensified after eating, physical activity, when in a position in the slope. In the physical examination of the chest, there may be a change in the percussion sound (tympanitis or dullness), weakening or lack of breathing in the lower lobes, intestinal noise can be detected, etc.
Hernias of the diaphragmatic hole are accompanied by pain and burning in the epigastrium and behind the sternum, heartburn, belching, vomiting, and sometimes dysphagia. Symptom is worse after eating, in a horizontal position, torso of the trunk. Sen's syndrome can be formed: a combination of hernia of the esophagus, cholelithiasis and diverticulitis of the colon. Rarely can there be relaxation of the diaphragm: congenital, caused by underdevelopment of the musculature, and acquired, formed during inflammation in the diaphragm, damage to the diaphragmatic nerve. They are accompanied by pains in epigastrium and hypochondria, shortness of breath, palpitations, a feeling of heaviness after eating, belching, nausea, constipation, weakness. Patients with frequent relapsing pneumonia have lower lobes.
The examination should include: lung and abdominal radiography, according to indications, a barium suspension and pneumoperitoneum (with a ready-made set for pleural cavity or thoracocentesis puncture), laparoscopy or thoracoscopy with artificial pneumothorax, FGS is performed with contrasting of the stomach and intestine. The aim of the study is not only to establish the pathology of the diaphragm, but also to conduct differential diagnosis with tumors of the esophagus, tumors and cysts in the liver, spleen.
Tactics: treatment is performed promptly, the examination is complex, so the patient must be admitted to the thoracic department, less often to the abdominal surgery department.