The percussion in the semiotics of the abdomen is of much less importance than the palpation, which is richer in relief; however, the percussion comes to confirm and specify the data of the palpation regarding the lower limits of the hypochondriac organs, to fix the upper borders of these organs, to demonstrate the presence of scarce abdominal effusions, to delimit the boundaries of the stomach and colon (better after air insufflation), to delimit the hollow organs containing air from the solid structures and in particular to demonstrate the presence of gas in the peritoneal cavity (pneumoperitoneum).
Normally the
percussion of the abdomen provides a tympanic sound, in relation to the presence of air contained under tension in the hollow viscera. Keep in mind that if the
consistency and the size of the liver are normal, the lower edge of the bowel can be appreciated only in those with very thin and loose abdominal walls, in
the deep breaths; at the epigastrium, given the thinness of the margin and the presence of the right muscles, the palpatory appreciation of soles is
particularly difficult. On the other hand, percussion is the only method that allows the delimitation of the upper edge of the bowel.
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At the hemiclavicular line A, this organ extends from the V intercostal space B up to the costal margin C; since the liver can lower by 1-3 cm during inspiration, a palpable hepatic margin is not always indicative of hepatomegaly |
To delimit the upper boundaries of the liver, percussion is performed on the anterior patient's supine wall and on the lateral and posterior wall when the
patient is seated; the percussion will be performed from top to bottom, according to the vertical lines of the thorax, while the patient breathes
quietly. The hepatic dullness must be distinguished in relative and absolute.
The first indicates the upper boundaries of the bowel which are covered by the lower pulmonary flaps and for which, therefore, it is necessary to use a strong
percussion, given their deep seat, ultimately resulting in a sound of non-absolute dullness, ie a relative dullness and therefore a hypophonic sound;
the second indicates the part of the viscera that remains uncovered from the lower limbs of the lung and this is to be found with a light percussion,
resulting in an absolute obtuseness.
The absolute dullness, therefore, coincides with the course of the lower margins of the right lung, while the upper limits of relative opusity run parallel to the first, 3-4 cm higher upwards; going backwards, this difference is reduced, as the extension of the lung covering the liver is reduced. The limits of relative dullness normally correspond: at the lower edge of the IV rib on the right marginal-sternal, at the upper border of the V rib on the parasternal, at the lower border of the V on the emiclaveal, at the 6th intercostal space on the anterior axillary, at the VII space on axillary medium, at the ninth apophysis spinous on the spondyloid line; that is, they coincide with those of the hepatic dome and come to draw on the chest a line, which rises up, going from back to front.
The upper limits of absolute dullness usually correspond: at the lower edge of the V rib on the right marginal to the upper border of the VI on the parasternal, at the lower border of the VI on the emiclavial, at the upper edge of the VII rib on the anterior axilla, at the lower edge of the VII on the average axel; at the VIII coast on the posterior axillary, on the IX coast on the angle of the scapula, on the XI coast on the paravertebral. The upper limit of liver opacity, both absolute and relative, descends by about 2 cm in the deep inspirations and about 1 cm in the transition from the supine to the erect position; about the same is the displacement at the bottom of the lower edge of the bowel. Due to the plural delimitation of the lower margin of the liver, a very light percussion must be used, given the tympanic resonance that this maneuver raises at the level of the stomach, the small intestine and the colon underlying the liver, favored by the subtlety of the margin.
Normally, in the supine position during the respiratory pause the hepatic border corresponds to the costal arch from the average axillary to the migraine, from where it starts to overflow, reaching 1 transversus finger
roughly between the migraine and the parasternal.
The trend of the hepatic border on the median line varies according to the constitutional type: it roughly cuts the xifoombelicale to half in the
normosplancnici, to the union of the superior third with the 2/3 inferior in the microsplancnici and to the union of the 2/3 higher with the lower third in
macrosplancnici; in the normotype it is introduced under the left rib arch between para-sternal and hemiclavic, in the macrosplancnico on the migraine and
in the microsplancnico on the left parasternal. The dimensions of the liver are evaluated by calculating the distance between the upper margin of absolute
opuseness and the lower margin of the bowel on the hemiclavic line. Normal values are affected by the constitution of the subject; in the adult male on
this line it measures 12 + 2 cm; it is 8-9 cm on the anterior axillary, 6-7 cm on the posterior axilla, 4-6 cm on the angle-scapular; anteriorly, the relative
dullness, as we said, measures 3-4 cm more.
To deepen the theme:
Epatomegalie: perchè un fegato è ingrossato?
Hepatic cystic changes and
other common injuries
L'anatomia del fegato
percussione aia fegato