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the muscles between the thorax and the pelvis supporting the abdominal wall. The lateral parts of the wall are formed by the transverse abdominis, the internal oblique, and the external oblique. Anteriorly, on each side, a segmented muscle, the rectus abdominis, spans the distance between the inferior thoracic wall and the pelvis. Other muscles supporting the posterior aspect of the wall are the quadratus lumborum, the psoas major, and the iliacus.
Abdominal MusclesThe large muscles of the anterior abdominal wall—external oblique, internal oblique, rectus abdominalis—which help breathing, support spinal muscles whilst lifting, and help maintain abdominal organs and GI tract in their normal position.
abdominal musclesClinical anatomy The large muscles of the anterior abdominal wall–external oblique, internal oblique, rectus abdominalis, which help in breathing, support spinal muscles while lifting, and help maintain abdominal organs and GI tract in their normal position
The abdominal muscles are made up of the cremaster, external abdominal oblique, iliacus, psoas major, pyramidalis, quadratus lumborum, rectus abdominis, and transversus abdominis muscles.illustration
See also: muscle
abdominal muscleslayers of muscle in the abdominal wall. The rectus abdominis muscles, strap-like, lie vertically each side of the midline; their action can be important in breaking the force of a blow. A 'three-ply' layer of flat muscles, each with the fibres running in different directions (external and internal oblique, and transverse) extend from the lower ribs to the hip bone, and from the sheath of the rectus muscles to the lumbar spine, thickest in the flanks. Actions include: forward flexion and rotation of the trunk; assisting expiration during deep breathing or against airway obstruction, by contracting as the diaphragm relaxes, or acting together with the contracting diaphragm to raise abdominal pressure in straining (urination, defaecation, childbirth) and in vomiting. Figure 1.
pertaining to, affecting or originating in the abdomen. See also abdominal paracentesis, abdominal sounds.
a wide bandage applied to the abdomen to raise intra-abdominal pressure. Its primary purposes are (1) to limit the displacement of the diaphragm during thoracic compression of cardiopulmonary resuscitation, thereby raising intrathoracic pressures achieved and improving forward blood flow, and (2) to maintain blood volume in the central circulation during hemorrhagic shock.
an abnormal form of respiratory movement in which the thorax is fixed and the inspiratory and expiratory movement of the lungs are carried out by the diaphragm and the abdominal muscles so that there are exaggerated movements of the abdominal wall.
the body cavity between the diaphragm and the pelvis; contains the abdominal organs.
may result from fluid effusions (transudate, exudate or blood), enlargement of viscera (neoplasia, dilatation, engorgement or physiological phenomena, e.g. pregnancy), intra-abdominal masses or fat. Weakness of the abdominal wall usually results in a pendulous rather than enlarged abdomen.
see abdominal lavage.
abdominal muscle ischemia
an unexplained ischemic necrosis of the internal oblique muscle of ewes in late pregnancy which are carrying twins or triplets. Results in ventral hernia but often with little apparent effect on the ease of lambing.
the paired muscles of the flank and belly that surround and support the abdominal viscera.
see abdominal pad.
may arise from an abdominal organ, the peritoneum or be referred as from spinal nerves.
arbitrary, descriptive subdivisions of the abdomen made up of three groups of three (like a noughts-and-crosses grid), three along the middle—xiphoid, umbilical and pubic, and three lateral pairs—hypochondriac, lateral abdominal and inguinal.
the shape of the abdomen viewed from behind.
see tunica flava abdominis.
the organs contained within the abdominal cavity; they include the stomach, intestines, liver, spleen, pancreas, and parts of the urinary and reproductive tracts.
consists of the parietal peritoneum, the deep and superficial layers of fascia, the transverse abdominal, internal and external abdominal oblique muscles, the subcutaneous tissue and the skin. It contains the umbilicus, the cicatrix marking the entry point of the umbilical cord, and is traversed by the inguinal canal, and at its caudal extremity carries the prepubic tendon, the ventral attachment of the wall to the pubic bones.
abdominal wall rigidity
reflex response to pain of peritonitis, accompanied by pain on palpation or percussion.