Proctology

Incompetence of the Anal Sphincter (Incontinence)

Incompetence of the anal sphincter (anal incontinence) is the partial or total disruption of the arbitrary or involuntary retention of the colon content.

Normal closing apparatus of the rectum is capable of holding solid, liquid and gaseous intestinal contents not only at different positions of the body, but during exercise, coughing, sneezing, etc. the Ability to hold the contents of the rectum depends on such circumstances as the quantity and quality of intestinal contents, as zamechatelnogo apparatus of the rectum and pelvic floor muscles, the integrity of the reflex arc and Autonomous innerviruemah colon and anal sphincter.

Causes

In accordance with the reasons of occurrence there are the following types of incontinence: post-traumatic, post Natal, functional and innate.

The most common cause of incontinence is injury of the obturator apparatus of the rectum, is most commonly associated with obstetric or surgical trauma. Then the frequency should be functional insufficiency of the anal sphincter, associated with diseases of the peripheral or Central nervous system. In third place are various anorectal malformations, which in the majority of cases complicated by insufficiency of the anal sphincter.

The most common cause of anal incontinence is a traumatic injury of the obturator apparatus. Among the damaging factors that lead to anal sphincter insufficiency, the most common is the surgical trauma of the muscle fibers of the sphincter during interventions concerning various diseases of the distal rectum and the perineum. The risk of damage to the sphincter especially great with the surgery abscess. More than half of patients in this group failure develops after surgery for chronic paraproctitis. Incontinence of intestinal contents occurs in 10% of cases after operations for acute paraproctitis, 6 % — after operations for recto-vaginal fistula and anal fissures, 7 % after hemorrhoidectomy and 3 % of cases after surgery for caudal teracom coloramerican fiber. Other causes of anal sphincter insufficiency, it should be noted domestic injury of the type “falling number”, traumatic rupture of rectum by foreign bodies, etc. Incontinence of the anal sphincter due to traumatic injury of the rectum and perineum is 11% of cases.

The cause of failure of postpartum anal sphincter in 20% of patients is birth trauma. Breaks crotch III degree in labor the most are often the cause of anal incontinence. This fact is due to the fact that the closure of the postnatal defects recto vaginal septum is often accompanied by suppuration of the wound, the divergence of the seam, the development of scar tissue that often leads to failure of the anal sphincter.

Functional disorders of the sphincter apparatus of the rectum due to the neuro-reflex disorders and pronounced local changes of the muscular structures of the pelvic floor and anal canal. The reason these disorders are often concomitant diseases of the rectum and anal canal. It is known that the atony of the anal sphincter occurs with proctitis, proctosigmoiditis, colitis. In these diseases as a result of inflammatory process disturbed state of the receptor apparatus suffers from motor function of the colon. Permanent stretching of the anal sphincter, occurs when the prolapsed hemorrhoid and prolonged rectal prolapse, leads to a decrease in the contractility of the obturator apparatus of the rectum.

Congenital deficiency of the anal sphincter due to two reasons: 1) congenital disorders of Central and peripheral innervation of the rectum, occurring when nezareatmene arches of sacral vertebrae, a herniated spinal cord; 2) atresia of the anal canal with complete or partial absence zamechatelnogo apparatus of the rectum. Congenital deficiency of the anal sphincter is quite rare.

Retention of intestinal contents — the key to successful treatment of any disease of the rectum. Studying the causes of incontinence of the anal sphincter, you need to imagine what is in the rectum retention of intestinal contents. It is provided by the interaction of the sensitive areas of the receptor apparatus of the distal rectum and anal canal, neural pathways sacral plexus, spinal cord and brain from muscular structures of the internal and external sphincters, supporting the tonic and willful hold. In addition, factors such as the closure of the anus, its slit-like form, anorectal angle, coordinated motor-evacuation activity of the colon, must be considered in the diagnosis and choice of treatment of incontinence of the anal sphincter.

In the development of anal incontinence in clinical and functional changes of the obturator apparatus of the rectum is isolated abnormalities in muscle structures and neuro-reflex pathology. Organic changes in the muscular structures of the anal sphincter without the expressed neuro-reflex defects characterized by the development of cicatricial process in the region of the anal sphincter.

Off reflex or a neuromuscular level in the complex system of anal retention causes various clinical manifestations of anal failure. Loss of function of the external sphincter leads to leaking of intestinal contents at the time of filling of the rectum. The patient while maintaining the defecation may not retain the intestinal contents during the filling of the rectum. In case of violation of innervation of the internal sphincter incontinence occurs when off conscious control of the function of the sphincter during sleep, emotional stress. With the defeat of the receptor apparatus of the distal rectum is no defecation and the presence of intestinal contents is only the perianal skin. With the defeat of the Central nervous system occurs a breakdown in communication and coordination of external and internal sphincters. It should be remembered that a violation of the receptor apparatus pathways or the Central nervous system, any surgical intervention will be ineffective.

Symptoms

There are three degrees of clinical manifestations of deficiency of the anal sphincter. When I degree patients do not keep gases, at the II degree — for this symptom with incontinence of liquid stool, third degree — the sick can’t hold all the elements of the intestinal contents. In addition to subjective feelings, when determining the degree of failure is of great importance to the objective characteristics of the contractility of the obturator apparatus of the rectum. Normal muscle tone of the sphincter according to sfinkterami equal to an average of 410 g at the maximum contraction of the anal sphincter it increases to an average 650 g. first-degree anal sphincter insufficiency indicators sfinkterami reduced to 260-360 g at the II degree — up to 130-300 g, at III — up to 0-180 g.

Classification and types

In the literature there are various classifications of anal sphincter insufficiency. In practice the most commonly used classification described above considering degree of failure. For each degree of failure are different types of treatment. When I degree of failure with sphincter defect of less than 25% of the main treatment is conservative. When anal sphincter insufficiency II—III degree surgical treatment.

It is recommended to use the classification, podrazdelyayutsya incompetence of the anal sphincter in the form of etiology, degree of retention of intestinal contents, at the clinical functional and morphological changes of the anal sphincter.

Classification of anal sphincter insufficiency

I. form:

1. Organic.

2. Inorganic.

3. Combined.

II. According to the etiology:

1. Congenital (associated with malformations).

2. Traumatic:

  • after operations on the rectum and perineum;
  • postpartum;
  • actually post-traumatic.

III. The degree of retention of intestinal contents:

1. I degree.

2. II.

3. III degree.

IV. According to the clinical and functional changes of the obturator apparatus of the rectum:

1. Violation of muscle structures:

  • internal sphincter;
  • external sphincter;
  • the pelvic floor muscles.

2. With neuro-reflex violations:

  • the receptor apparatus;
  • conductive tracks;
  • the Central nervous system.

V. the morphological changes of the obturator apparatus of the rectum.

1. With the localization of the defect of the muscles around the circumference of the anal canal:

  • on the front wall;
  • on the rear wall;
  • on the side wall;
  • on several walls (a combination of defects);
  • the entire circumference.

2. For the length of the defect of the muscles around the circumference of the anal canal:

  • up to a quarter of a circle;
  • a quarter of a circle;
  • up to half of the circumference;
  • half of the circumference;
  • three-quarters of a circle;
  • absence of sphincter.

Complications

In the complicated form of insufficiency of the anal sphincter, it is advisable to allocate its combination with chronic abscess, recto vaginal fistulas, strictures of the anal canal. Patients with this form of the disease account for 17 % of all patients with weakness of the anal sphincter. Difficulties of treatment are exacerbated by the presence of purulent process, as observed in patients with chronic abscess or the presence of a pronounced scar process, after repeatedly surgery.

Diagnostics

The diagnosis of insufficiency of the anal sphincter is primarily based on the complaints of the patient on the incontinence of gases and feces. Patient survey carried out on the gynecological chair in the same position as for hemorrhoidectomy. In this estimate the closeness of the anus and its location, the presence of cicatricial deformity of the perineum and anus, the condition of the skin of the perianal area, sacrococcygeal area and buttocks. Sometimes when inspecting the perineum and anal opening, you can identify these comorbidities this area as anal fissure, hemorrhoids, fistula, or rectal prolapse. Palpation of the perianal region helps to determine the cicatricial process, the subcutaneous portion of the external sphincter.

The great value has a digital rectal exam, which determines the presence and length of the scar process, the spread of it within the walls of the anal canal, elasticity and length of the sphincter, the preservation and condition of the pelvic floor muscles. Also determine anatomical relations of the muscular and skeletal structures of the pelvic ring. The doctor notes the tone of the sphincter of the anus, the character of its reduction, the presence of the hiatus after removing the finger.

Anoscopy enables you to visually examine the walls of the anal canal and distal rectum and to determine the extent of the scar process. With sigmoidoscopy to examine the mucosa of the rectum and distal sigmoid colon. If proctography determine the relief of the mucous membrane of the rectum, the magnitude of the anorectal angle, condition of the pelvic floor. In addition, patients undergo a barium enema with double contrast. This study allows to assess the condition of the colon, to detect presence of narrowed and extended areas, fecal stones, abnormal arrangement of the colon.

Often patients with urinary intestinal contents noted unstable stool, bloating, flatulence. In the study of intestinal flora they quite often reveal a goiter, so in the survey include bacteriological examination of feces by inoculation of selective aerobic and anaerobic culture medium. According to indications in patients with postpartum trauma and recto vaginal fistula, be sure to study the degree of purity of the vagina.

Great importance in the diagnosis and assessment of extent of scar process and that of insufficiency of the anal sphincter are the physiological methods of research. The most common method of assessing the functional state of the obturator apparatus of the rectum is sfinkterami, which is determined by contractile function of the external and internal sphincters. The magnitude of the tonic stress in a greater degree characterizes the condition of the internal sphincter, and volitional contraction — contractility of the outer. The study of the contractility of the muscles of the obturator apparatus is allowed to establish average norms for both sexes. Found that when the traumatic nature of incontinence reduced tonic and an arbitrary pressure in the region of the external sphincter, and in congenital deficiency of the anal sphincter is often altered reflex activity of the external and internal sphincters, decrease the total pressure in the anal canal and the nature of the pressure in the projection of the internal sphincter.

A particular value in the study of the obturator apparatus of the rectum is electromyography. It is established that the external sphincter and pelvic floor muscles have a continuous electrical activity, the value of which changes at random and reflex influences.

An important component in determining the state of the obturator apparatus of the rectum is the assessment of the anal reflex. In the study of the contractility of the sphincter muscles and the severity of the anal reflex identified a direct correlation between them. Study of the anal reflex is carried by a dashed irritation of the perianal skin bellied probe. The reflex response is estimated alive (or normal), when in response to irritation occurs a complete reduction of the external sphincter; increased — when at the same time as the sphincter is the muscle contraction of the perineum, sometimes the buttocks and bring the hips; weakened — if the reaction of the external sphincter is barely visible.

The most complete picture of the functional status of the anal sphincter gives profilometry is a method of evaluating geometrical model of the intracavitary pressure. Using the appropriate computer program, you can register pressure throughout and have a clear idea of the spread of the scar process, and the degree of dysfunction of the anal sphincter.

These methods of research allow to determine the functional state of the obturator apparatus of the rectum, to evaluate the basic properties of the muscular frame and nervous-receptor apparatus of the rectum to delineate functionally intact sphincter muscles of the anus and pelvic floor. In individuals with impaired retention of this complex allows to determine the degree, nature and extent of the lesion, that determines the choice of treatment and the type of surgical intervention aimed at correcting the obturator apparatus of the rectum.

Treatment

At the mixed form of incontinence, affecting the nervous and muscular structures must carry out a comprehensive treatment as to pre-and postoperative period.

Conservative therapy as the primary and only treatment indicated for patients with non-organic insufficiency of the anal sphincter, in particular developed as a result of rectal prolapse or hemorrhoids. This type of treatment is used in patients with I—II degree of weakness of the obturator apparatus of the rectum, and in violation of the neuro-reflex connections at various levels, atrophy of muscle fibers of the anal sphincter, associated with changes in the Central nervous system. In addition, conservative treatment to be patients with organic lesions of the sphincter with a linear defect for one quarter of the circumference of the anal canal on skin and mucous level, with involvement of superficial layers of muscles of a press and the lack of deformation of the walls of the anal canal. Conservative treatment includes electrical stimulation of the muscles of the anal sphincter and perineum, a set of physical therapy and drug therapy. Electrostimulation actively affects the obturator apparatus of the rectum, increases tonic muscle tension. Therapeutic exercises aimed at increasing strength, improving contractile ability of muscles. Drug treatment aimed at improvement of excitation in the neuromuscular synapses and activity of muscle tissue.

Surgical treatment most patients with organic weakness of the anal sphincter. The indication for surgical correction are the defects of the sphincter size from one quarter of a circle and more, the spread of cicatricial process in the muscles of the obturator apparatus of the rectum, the deformation of the walls of the anal canal. Surgical treatment is indicated for patients with weakness of the anal sphincter II—III degree, developed as a result of rectal prolapse with the presence of atrophy of the pelvic floor muscles, violation of the anatomical relationship of the muscles of the obturator apparatus. Contraindications to surgical correction is the defeat of the Central and peripheral nervous system innervating the pelvic organs.

Organic damage to the muscular structures of the obturator apparatus without the expressed neuro-reflex violations are subject to surgical treatment. The nature of the surgery is determined by the location of the defect of the muscles around the circumference of the anal canal, extent and prevalence of cicatricial process.

Operation of stone the movement of the distal rectum in the remaining obturator apparatus can be performed in patients with congenital dysfunction of the hold content and the location of the anus outside the anal sphincter.

Patients with organic deficiency of the anal sphincter the I—II degree, with the defect extending up to one quarter of the circumference of the anal canal, the proliferation of scarring process at the level of the perianal skin, mucous membranes and the sphincter muscles, any localization of the defect on the circumference of the channel, the deformation of the hole of the anus is sphincteroplasty.

With more severe changes of the obturator apparatus of the rectum perform sphincteroplasty. The indications for it are organic sphincter insufficiency II—III degree, the existence of the defect to one quarter of its circumference on the front or back of the semicircle of the anal canal, the spread of cicatricial process in the sphincter muscle of the anus, as well as the insufficiency of II—III degree, developed as a result of rectal prolapse after the elimination of the latter.

In case of insufficiency of II—III degree with the defect of the sphincter up to one third of a circle and its localization in the lateral or anteroposterior the semicircles, the proliferation of cicatricial process in the sphincter and pelvic floor muscles need to form the obturator apparatus of the rectum and strengthen the pelvic floor. With this purpose, perform sphincteroplasty — replacement of defect of the sphincter of the short flap gluteus Maximus.

The greatest difficulty is the treatment of patients with extensive defects of the anal sphincter, or lack of either acquired or congenital in nature. It can be patients after various injuries of the sphincter or a congenital absence of the muscles of the obturator apparatus of the rectum. This raises the necessity of forming a practically new obturator apparatus.

In patients with extensive damage to the anal sphincter optimal are the creation of an artificial obturator apparatus of the distal rectum and the pelvic floor formation of long flaps by one or two large gluteal muscles. The operation can be performed in 1 or 2 stages, alternately using the right and left gluteal muscles. The feasibility of this technique due to the fact that large glutes compared to the other closest to the rectum. They have a large mass, have long muscle fibers. Innervation of them, as the muscles of the external sphincter, is from the sacral plexus. Large gluteal muscle, if necessary, by subtracting, contribute to the external sphincter to hold the bowel contents.

Conducted anatomical-topographical and experimental studies allow to introduce into clinical practice the original operation — the formation of the obturator apparatus of the rectum fasciale-muscle graft tender thigh muscles.

In addition to muscle plastic, used in clinical practice device, which is a elastic filled with air, the balloon is placed around the distal colon in the form of a circular cuff. This kind of surgery is accompanied by high frequency of complications caused by implantation of the device.

Muscle plastic remains the most promising method to solve this problem it is necessary to study the methods and results of the formation of the obturator apparatus of the rectum of tender thigh muscles.

Forecast. In General, the use of conservative and surgical treatment allows to achieve recovery or improvement of function of holding the absolute majority of patients.

Reviewed by the QSota Medical Advisory Board