DISEASES OF RECTUM AND TAIL Paralysis of the Rectum Although by no means a common condition, paralysis of the rectum is occasionally met with as a result of spinal injury, or as a part of a generalized paraplegia. The muscles of the tail are frequently involved, and in some instances the bladder and the retractor penis muscle become paralysed simultaneously. Aged animals appear to be more frequently affected than younger ones, probably on account of senile changes occurring in the lumbar region of the cord and its meninges. In these cases there is frequently chronic dilatation or"bal looning"of the rectum with atony of the walls, and a continual accumulation of faeces.
In a case recently observed in a five-year-old gelding which had fallen down a steep bank, the following symptoms were noticed: from the commencement the retractor penis muscle was paralysed so that the penis constantly protruded from the sheath and hung pendulous. The bladder was partially affected, the urine being expelled in small quantities at a time with apparent effort. The rectum was completely paralysed and was found to be greatly dilated and packed with faeces, which were removed by hand twice daily, otherwise the horse manifested symptoms of colic.
Treatment was mainly expectant, though cold water enemas and nerve stimulants were ad ministered throughout.
The bladder regained its power at the end of ten days, the penis became retracted into its sheath at the same time. The rectum remained paralysed for three weeks, after which recovery was gradual. After two months the horse defmcated in a normal manner.
Whilst cases arising from spinal injury may thus recover, it must not be imagined that prognosis is always favourable.
In aged horses, and when the symptoms form part of a generalized paraplegia, the prognosis is decidedly unfavourable. In paralysis of the rectum dependent upon injury the prognosis must always be guarded, as in many cases it is impossible to diagnose the exact amount of damage done to the cord or its nerves, and fracture occurring in the lumbar region cannot be detected with any degree of certainty.
A form of rectal paralysis is often evident as a symptom of general intestinal paralysis, and is 'indicated by relaxation of the sphincter ani and failure of the rectal walls to contract upon the hand when inserted. Should peristalsis become re-established in the intestines the rectum again commences to contract.
A similar condition is often seen in cattle after acute diarrhoea, the anus being widely opened and the rectum empty and"ballooned." In some cases the muscles of the tail become simultaneously affected so that the long hair becomes soiled with urine and faeces. In advancing paralysis the tail is almost constantly affected, whilst the bladder and lumbar muscles become involved generally at a later stage.
Treatment. This is usually more or less use less, as in cases of paraplegia the administration of medicines is quite futile, whilst in accidental injury to the spine, recovery, when it does occur, is a matter of time.
Emptying the rectum by hand must be practised at least twice a day, whilst some practitioners recommend the use of cold water enemas. Nerve tonics have little effect, though subcutaneous injections of strychnine and small doses of arecoline may be beneficial, but the rectum should be emptied by hand previously. In cases of injury to the lumbar region, counter irritation can do no harm, and may be of advantage.
Paralysis of the Tail In the majority of cases paralysis of the tail either accompanies rectal paralysis or is the forerunner of this affection. At a later stage, general paraplegia, with anaesthesia of the pos terior extremities, atrophy of muscles, and paralysis of the bladder, usually sets in.
The condition seems to be due to gradually developing sclerosis of the cord in the lumbar or sacral region. Dexter observed fatty degenera tion of the muscles of the tail, dilatation of the rectum, and changes in the mucous membrane of the bladder. The cauda equina was greatly thickened, and contained masses of connective tissue interposed between the nerve bundles, with partial fatty degeneration of the nerve elements, and constriction of the vessels from pressure. A similar condition was present in the spinal ganglia of the lumbar and sacral regions. (See Regional Veterinary Surgery and Operative Technique, A. W. Dollar.)
We have observed cases of unilateral paralysis of the curvator coccygis muscle in two horses which formed part of a stud of hunters. The exciting cause could not be discovered. The tail in each instance as well as being carried to one side was also curved throughout its length. One case recovered in a few days; the other, in spite of all treatment, continued to be carried laterally.
Prognosis in most cases is very unfavour able. Treatment is of no avail. Stimulants, massage, and electricity have all been tried without success. Cases of paraplegia have to be slaughtered eventually.
Tumours of the Tail Botryomycosis of the tail is sometimes met with, principally in horses which have been recently"docked."Cases, however, not infre quently occur several years after this operation has been performed, and it would almost appear that the organisms responsible lie latent in the tissues for considerable periods. The same re mark applies to invasion of the spermatic cord and muscular tissues of the shoulder and other parts, in which lesions often do not occur until some considerable period after the in fliction of the wound or other injury which it is surmised has been the point of entry of the organisms.
Various other growths may invade the tissues of the tail. In aged grey horses melanomata are not uncommon, and may appear either upon the sides or at the root of the tail, whereas botryomycomata usually occur at the extremity extending towards the base. Fibromata are not very common at this situation, but are occasionally met with. Carcinomata and sarco mata sometimes occur, more especially in aged animals, but are decidedly rare growths in this region.
Occasionally large vascular tumours appear on the tail, particularly in cattle. They appear to consist of a mass of varicose vessels with a moderate amount of fibrous connective tissue surrounding them.
Treatment. Tumours occurring at the ex tremity of the tail arc best removed by"dock ing"as far above the growth as is compatible with a good appearance. When the diseased condition extends to the bone or when malignant growths exist upon the stump of the tail it will be necessary to amputate two joints above the point of origin of the tumour, otherwise healing is subsequently incomplete, and the growth is liable to recur. We once"re-docked"a horse which was affected with carcinoma of the end of the tail upon two separate occasions, but the growth recurred after each operation, and the animal being of little value was subsequently destroyed. Probably had a larger portion of the tail been removed at the first operation the result might have been more satisfactory.
Tumours occurring at the side of the tail or at any point above the stump may be dissected out when docking is out of the question, but malignant growths can only be got rid of by amputation of the tail. Docking close to the root of the tail is an unsatisfactory operation as it leaves a large stump uncovered by hair. The flap operation leaves a far larger area of skin provided with hair roots, which will provide a natural covering of some length, and which will to some extent obviate the unsightly appearance which would otherwise arise from the operation of docking.
The operation is performed as follows: After clipping, shaving, and disinfecting the tail, a tourniquet is applied around its root. Two flaps, one on the dorsal, the other on the ventral surface, are then formed by means of curved incisions meeting on the lateral surfaces of the tail. Whilst these are held apart by an assistant, the tail is amputated by dividing one of the caudal articulations. After releasing the tourni quet the bleeding vessels are picked up with forceps and twisted, or they may be ligatured separately with fine silk. The edges of the flaps are then trimmed to the required shape and length, brought into apposition, and held in position by closely applied interrupted sutures, whilst one or more deep"quilled"sutures are inserted so as to bring the inner surfaces of the flaps into contact, and obliterate any cavity which might otherwise exist between them.