The lumbar region, occupied to a large extent by the kidneys, is limited on the inside by the vertebral column, below by the iliac crest, above by the twelfth rib. On the outside it is continuous with the abdominal wall on a level with the flank.

The frequency of traumatisms of the kidney has not been precisely determined. They are included, and not without reason, amongst wounds of the abdomen.

The antero-posterior course is the most frequent, then come the postero-anterior and the transverse directions. The descending colon and the spleen on the left side, the ascending colon and the liver on the right, and the pleura on each side, are often simultaneously injured.

Contusions are rare, and without much interest; bleeding excoriations, cul-de-sac wounds, through-and-through perforating wounds, are the lesions generally seen. The extent of the perforations is in proportion to the velocity of the projectile. If the latter is slight or average, the track is narrow, and not, or very little, fissured ; it is wide and fissured with great velocity and with a short range. The perforations are clear or prolonged by multiple and starred fissures, especially near the aperture of exit. In explosive firing the kidney may burst; the organ is fissured, deeply divided, separated into several bleeding fragments. The post-renal cellular tissue, less divided than the renal tissue, partly obliterates the posterior wound.

The pelvis of the kidney and the ureter are divided, perforated, and torn. Their lesions give rise to a flow of urine, which may become infiltrated in the perirenal tissue; On the other hand, wounds of the parenchyma by bullets do not produce any outflow of urine.

Wounds of the renal arteries and veins are followed by serious haemorrhage, and with these lesions there is a risk of mortification of the kidney.

Outflow of urine from the posterior wound, a pathognomonic sign, is exceptional (parenchymatous lesions, narrowness of the wound, mixture of urine and blood). Infiltration of urine, which may form a lumbar urinary tumour, with a tendency to diffusion towards the iliac fossa behind the peritoneum, is a characteristic of wounds of the pelvis of the kidney or the ureter.

Haematuria, a characteristic symptom, lasting generally for several days, is a very valuable sign, but it has been observed in only one-thirty-fifth of the peripheral wounds. it would seem only to occur in central wounds.

Oliguria and anuria must also be mentioned.

The relations of the external apertures with the region occupied by the kidney furnish very valuable indications in the diagnosis. In width, the kidney occupies the middle third of the space included between the spinous apophyses and the lateral section of the body, and in height, the space that extends from a superior horizontal line passing across the eleventh rib, to an inferior one which would just touch the second or third lumbar vertebra.

The immediate treatment presents nothing in particular: wide dressings, absolute rest, nothing to drink. We must not meddle with renal effusions when they are aseptic.

For retention of urine, repeated catheterism, or a catheter tied in.

For profuse haemorrhage, general haemostatics; in case of insufficiency, lumbar incision, search for the kidney, direct compression by means of an aseptic pad, fixed by a partial suture to prevent its being pressed out, its action being assisted by an anterior compression of abdomen by a pad of cotton-wool.

We should not meddle with a fissured, even a divided kidney; the fragments which are nearly free are alone to be removed.

For the urinary outflow or a perinephritic abscess, lumbar incision. For pyonephrosis, nephrotomy.

The gravity of these wounds is especially due to both the kidney and the colon being injured; isolated wounds have generally a rather favourable prognosis. They usually heal in two or three weeks. With regard to complicated wounds, their mortality was formerly 50 per cent. (haemorrhage, one-third of the deaths; infection complications, two thirds), but the bad prognosis has diminished with the present bullets, although it is impossible to give precise information on this point.

Chapter 18

Wounds of the Region of the Pelvis