ABDOMINAL WALLS, Diseases of. But little more will be needed in this article than to give a brief outline of the nature of the affections to which the abdominal walls are liable, as most of these are but local forms of diseases which are fully described in other parts of this work. The parietal peritoneum will be excluded from consideration, as its morbid conditions are treated of separately.
1. SUPERFICIAL AFFECTIONS. --
a. The skin covering the abdomen may be the seat of various eruptions. The rash of typhoid fever is chiefly observed over this region.
b. When the abdomen is greatly enlarged, its cutaneous covering becomes stretched and thinned, often presenting a shining appearance, this may even give way, so that it exhibits superficial cracks or fissures. If it has been distended for a considerable time or on several occasions, as after repeated pregnancies, the skin becomes impaired in its structure, and is often the seat of permanent white lines or furrows--lineæ albicantes. In this connection allusion may be made to the umbilicus, which, in certain forms of distension of the abdomen, may become pouched out, everted, or actually obliterated.
c. The veins of the skin frequently become enlarged and tortuous, when the return of the blood which is normally conveyed through them is in any way impeded. The particular vessels which are distended will necessarily depend upon the seat of the obstruction.
d. The cutaneous sensibility over the abdomen is sometimes materially altered. In certain nervous diseases it may become more or less impaired or lost; but the most important deviation is a marked increase of sensibility -- hyperæthesia -- which is occasionally observed in hysterical females, and which may simulate more serious affections, particularly peritonitis, especially if it is accompanied with symptoms of much depression. This condition is characterised by extreme superficial sensibility or tenderness of the abdomen, the slightest touch being resented; but if the patient's attention can be taken off, and deep pressure be then made, this is borne with little or no indication of distress. The aspect of the patient, the presence of other symptoms indicative of hysteria, and the absence of pyrexia, usually serve to distinguish this affection from others of a graver nature. The surface of the abdomen may also be affected with neuralgia, which is sometimes very severe.
2. SUBCUTANEOUS ACCUMULATIONS. --
a. The chief morbid condition coming under this head is oedema or dropsy of the subcutaneous tissue. This generally follows anasarca of the legs, and may be associated with ascites. The fluid tends to collect especially in the lower part of the abdominal walls and towards the flanks. The skin often presents a white pasty aspect; the abdomen may be more or less enlarged; the umbilicus appears depressed and sunken, if the oedema extends up to this level; the superficial structures pit on pressure, and yield the peculiar sensation of dropsical tissue; and the percussion note is frequently muffled.
b. The abdominal subcutaneous tissue is, in many persons, the seat of an abundant collection of fat, which may be important from its causing general enlargement, and simulating or obscuring other more serious morbid conditions which enlarge the abdomen.
3. AFFECTIONS OF THE MUSCLES AND APONEUROSES. --
a. The abdominal walls may be the seat of muscular rheumatism, which is particularly likely to follow undue straining, such as that caused by violent coughing or vomiting. It is characterised by pain, sometimes severe, evidently located in the muscular and tendinous structures, accompanied with much soreness and tenderness. The affected parts are kept as much at rest as possible, and any action which disturbs them materially aggravates the pain.
b. As the result of violent strain, the muscular or aponeurotic tissue may be more or less torn or ruptured. As a consequence a protrusion of some internal structure may take place, forming a hernia.
c. The abdominal muscles are liable to be the seat of spasmodic contractions, cramp, or rigidity. These are not uncommonly excited in sympathy with grave disturbance of the alimentary canal, as in cholera. In certain painful internal affections also some of the abdominal muscles are occasionally kept in a state of more or less rigid tension, as if they were involuntarily contracted in order to protect the diseased parts underneath from injury. The spasmodic contractions in tetanus not unfrequently cause great suffering over the abdomen.
d. On the other hand, the abdominal muscles are occasionally paralysed, as the result of centric nervous disease. The movements of respiration are then altered in character; while the expulsive acts in which the abdominal muscles naturally take part are much interfered with.
4. RELAXED ABDOMINAL WALLS. --
All the structures forming the walls of the abdomen are often in a relaxed and flabby state, yielding to any pressure form within, so that the abdomen becomes enlarged and prominent, especially if, as is frequently the case, this condition is associated with much flatulence. It materially weakens the act of defæcation, and promotes constipation.
5. INFLAMMATION AND ABSCESS. --
Local inflammation may be set up in any of the abdominal structures, and this may terminate in suppuration and the formation of an abscess. Purulent accumulations from within, as in cases of pelvic abscess, as well as certain abscesses originating in diseases of bones or joints, may likewise extend among the tissues of the abdominal walls, causing thickening and induration, or may make their way outwards, directly or through a sinus. Subsequently permanent sinuses or fistulæ may be left.
6. The abdominal wall may be the seat of extravasation of blood; and various kinds of tumour or new growth may form in its structures.
-- Frederick T. Roberts.