OTHER FORMS OF HERNIA.
The other forms of hernia (umbilical, inguinal, scrotal, femoral, ventral, vaginal, ischiatic) are essentially surgical and need not be further referred to here, than to guard the reader against overlooking them as factors in producing intestinal and omental strangulation and colic. They are all to be recognized by the presence of a local swelling, which may often be obliterated by returning its contents into the abdominal cavity, which sensibly enlarges when the animal is made to cough, and which, if made up of intestine, is subject to gaseous distension, and gurgles when manipulated and returned. A violent colic occurring in a male animal should never be considered as certainly diagnosticated until the scrotal and inguinal region have been carefully examined for hernia.
PARALYSIS OF THE RECTUM.
In solipeds, ruminants, swine, carnivora. Injuries to loins and croup. Palsy of tail and sphincters. Nerve centres in end of cord. Fractures and dislocations of the pelvis. Hæmoglobinuria. Advanced gestation. Sclerosis. Ovariotomy by vagina. Impaction of rectum. Neoplasms. Thrombosis of internal iliac artery. Ptomaines and toxins in fevers. Symptoms: tardy defecation, impaction, over distension, fæces firm, dry, roller like, liquid oozing, excoriation, foul tail and thighs, bulging of anus, incontinence of urine. Paresis and wasting of quarter. Treatment: remove cause, for sprains and fractures sling, treat myelitis, debility, poisoning, unload rectum often, oily or soapy enemata, strychnia, eserine, ergot, barium chloride, derivations.
This is much more common in the horse than in ruminants, swine or carnivora, mainly because the soliped is more exposed to traumatic injuries of the loins, croup, and pelvic bones. It is noticeable that in the majority of cases the paralysis of the rectum is connected with palsy of the tail, anus, and sphincter vesicæ. This comes from the anatomical fact that the centres presiding over the motions of these different parts are situated close to each other in the terminal portion of the spinal cord, and any lesion of that part by traumatism or disease is likely to affect all of these parts alike.
The condition has been especially noticed in fractures or severe sprains of the loins causing pressure on the spinal cord. In some cases injury to the nerves supplied by this part of the cord, leads to an extension of inflammation to the nerve centres, thus paralysis of the rectum has followed on fracture of the ischium, dislocation of the sacro-iliac joint, or even of the first bone of the coccyx. Again, congestions and effusions on the terminal part of the cord, which occur in certain cases of hæmoglobinuria and in old hard worked horses is a cause of these local paralyses. Advanced gestation appears at times to produce the disease through pressure on the nerves, though it has also been noticed in non-breeding animals, and is doubtless traceable to sclerosis or other degenerations of the cord. It sometimes follows vaginal ovariotomy.
Sometimes the condition is traceable to local lesions as over distension of the rectum in horse or dog or in rectitis, but the result in such cases is usually partial, a paresis rather than a paralysis. The same may at times result from the growth of the neoplasms, and from the debility of old age. In other cases thrombosis of the aorta or internal iliac artery, implicates the hemorrhoidal vessels and paresis occurs as a result of the limited blood supply.
It may further result from the action of toxins and ptomaines on the spinal cord as when it supervenes in the course of debilitating fevers. This usually shows itself first as paresis of the sphincter ani, and later implicates the rectum as well.
Symptoms. In the slighter forms defecation is retarded, the fæces accumulate and overdistend the organ, adding to the paresis; they escape only under violent straining and apparently by the peristaltic contractions of the anterior portion of the rectum; the ejected matters are discharged usually in the form of a cylindroid mass; and they are dry, and firmly compressed. In some cases the irritation caused by the impaction leads to a free secretion, which escapes through the widely open anus and runs down the thighs, leading to excoriation of the skin.
In the more severe cases the accumulation is more complete, the expulsion still more difficult, and as the tail is often implicated, it lies flaccid between the thighs, and is smeared with the discharges. The peristalsis in front and the forcible compression by the abdominal muscles may be entirely inadequate to effect defecation so that the fæces have to be removed by the hand. The pressure on the bladder often leads to incontinence of urine, if the paralysis of the vesical sphincter has not already brought this about.