Fecal incontinence is defined as involuntary emission of gaseous and / or liquid faeces and / or solids through the anus. The accident may be episodic, during such an episode of diarrhea. This incontinence may also be an expression of disorders of higher intellectual functions or loss of autonomy.
Fecal incontinence is common in France since it concerns 11% of the population surveyed.
It is often severe because results in involuntary loss of stool in half the cases, which occur on a weekly basis at least once in three. It is estimated that 2% of the French suffer from incontinence for stool once a week.
This prevalence increases if one focuses on the study of risk groups that is to say those having undergone surgery proctology, rectal malformation carriers children, elderly people in institutions or those suffering from neurological disease central or peripheral. Obstetric factors have a great place, if not the most important in the genesis of female fecal incontinence.
The socioeconomic impact of fecal incontinence is considerable, determining professional absenteeism and a cost of significant support.
Physiology:
The colon is a material storage organ that plays an important role in fecal continence, also ensured by a capacitive system, rectum, and a resistive system, the anal sphincter.
Colon temporarily stores the stool and about once a day, a peristaltic contraction which arises from the transverse pushing intraluminal contents in the rectum causing the need exonérateur.
The rectum is normally empty. Mechanoreceptors, located in the rectal mucosa, are sensitive to pressure variations upon the arrival of the fecal bolus and are causing the need exonérateur. Upon the arrival of feces, the viscoelastic properties of the rectum enable it to let distend and adapt its volume to its content. This rectal compliance helps to remove the need exonérateur and postpone the evacuation of feces.
The sphincter resistive system consists of the internal anal sphincter made of smooth muscle fibers and the external anal sphincter composed of striated muscle fibers. The beam puborectal the levator ani muscle is responsible for the permanent angulation of the anal canal, an essential factor of continence.
The internal anal sphincter is in permanent contraction, responsible for most of the anal resting pressure. The external anal sphincter provides emergency continence and opposes the intra-abdominal pressure rises (coughing, sneezing, etc.).
The external anal sphincter and puborectale strap are innervated by the pudendal nerves. The sympathetic system to a significant part in maintaining fecal continence since it plays an exciting role in the internal anal sphincter.
Continence is an intermittent function whose learning is imposed by sociocultural norms. Indeed, apart from the times when the subject perceives the need, the rectum is normally empty, and continence is assured by the colon.
The arrival of the fecal bolus (either material or gas) determines rectal distension.
This causes a feeling of distension need on the one hand and a reflex relaxation of the internal sphincter, offset by the contraction of the external sphincter. This opening of the top of the anal canal is contacted rectal contents with a sensing zone which allows to recognize the liquid, gaseous or solid rectum.
When evacuation is deferred, the emergency continence provided by the external sphincter allows time for rectal compliance to adjust the volume of fecal bolus and thus reduce the need for sensation.
DIAGNOSIS:
Examination and examinations:
Careful questioning can easily replenish perineal surgical history, obstetrical, diseases that may affect the intestinal transit or sphincter function.
Clinical examination ideally in genupectorale position allows to observe and assess the state of the perineum: state of the anal margin, persistent radial folds.
Digital rectal examination appreciate subjectively the anal sphincter tone itself as well as that of the puborectale strap. When rectal examination, it is useful to push the patient to search previous rectocele, then ask him to contract his sphincter, allowing an appreciation of residual capacities contractions of the perineum. Sphincter rupture is easily recognized in this way.
DRE also allows to assess the existence or not of stool in the rectum, usually empty.
Rectoscopy assesses the state of the rectal mucosa and eliminating inflammation that could contribute to lower the compliance of the rectum (ulcerative colitis).
After these examinations, diagnosis and therapeutic management can be achieved for a majority of patients.
Functional Explorations:
Functional explorations take on their interest in a second time in case of failure of the medical or surgical management.
The main investigations are anorectal manometry, electrophysiological explorations, the endosonography and radiologically, defecography.
Anorectal manometry:
It allows the detection of the anorectal inhibitory reflex (which allows the opening of the internal sphincter when the distension of the rectum).
It mainly studies the rectal capacity and compliance. It also encrypts the values of the resting tone of the sphincter and its voluntary contraction. These figures can be used as reference subsequently when rehabilitation or surgery.
Electrophysiological explorations:
This is the sphincter electromyography one hand and the measurement of latency of the pudendal nerve. This very simple examination can diagnose denervations related to stretching of the nerve in the perineal descent in patients with a descending perineum (thrust forces during constipation, stretching in successive deliveries). The existence of a perineal denervation is a poor prognosis for rehabilitation.
The interest of these explorations first line is not constant, but it must predict whether surgical treatment is planned.
Ultrasound endoanal:
This technique allows perfect anatomic visualization ruptures external and internal sphincters. Through this review, the frequency of sphincter ruptures postobstétricales was significantly revised upwards. If a complete sphincter rupture is usually easy to detect clinically, partial rupture, especially the internal sphincter, is more difficult to recognize clinically.
Dynamic Defecography:
It is a both morphological and functional examination. Is carried opacification of the rectum with a viscous contrast medium and performing the snapshots at rest, thrust retainer and evacuation. This allows to recognize a perineal descent, the existence of a rectocele, to assess the anorectal angle.
It is useful to opacify the small bowel prior to search elytrocele, to an opaque marker in the vagina and the bladder opaque to create a full pelvigraphy to better understand all of the perineal static.
ETIOLOGY:
The function of the various elements described above may be faulty and determine disorders of anal continence.These causes are detailed in Boxes 1-4.
Achievement of anal sphincter and pelvic floor mechanisms:
The main causes of the achievement of anal sphincter and pelvic floor mechanisms are presented in Box 1.
Box 1. Achievement mechanisms anal sphincter and pelvic floor
Functional neurological damage (denervation sphincter)
Pudendal neuropathy stretching
Descending perineum syndrome
Trauma of the pelvic nerves, sacral, spinal conus
Diabetic neuropathy
Myelomeningocele
Sacral agenesis, fixed cord, spinal lipoma cone
Anatomic sphincter injury
Obstetric trauma (degree tear 3 or 4, sphincter injury)
Traumatic postsurgical (anal fistula, hemorrhoidectomy, sphincterotomy, forced anal dilatation)
Anal tumor
Inflammatory bowel disease
Sphincter congenital malformation
Imperforate anus
Rectal prolapse
Primary degeneration of the internal anal sphincter
Trouble intestinal transit:
The essential role of the distal colon is the storage of solid feces. In case of diarrhea, whatever its origin (inflammatory, infectious, malabsorption or if bowel resection), the colon loses this storage capacity. The materials then come quickly and frequently in the rectum overflowing resistive capabilities of a fully functional even sphincter.
The main causes of diarrheal statements are presented in Box 2.
Box 2. diarrheal states: abnormal stool consistency
Irritable bowel syndrome
Infectious diarrhea
Syndrome of malabsorption
Radiation enteritis
Infl ammatory chronic disease of the intestine
Laxative abuse
Short bowel syndrome
Reduced capacity or the compliance of the rectum:
The rectum distensibility who lost properties as can be observed in ulcerative colitis determines an inability to adapt to volume changes: this determines a rapid rise in rectal pressure that can not be offset by the contraction voluntary external anal sphincter.
The main causes of the reduction in capacity or rectal compliance are presented in Box 3.
Box 3. Capacity reduction or rectal compliance
Inflammatory proctitis
Sphincter preservation surgery (low anterior resection, colo-anal anastomosis, iléoanale, ileorectal)
Rectal tumors
Radiation proctitis
Ischemic proctitis
Connective (scleroderma, dermatomyositis, amyloidosis)
Extrinsic compression
Neurological pathology:
Neurological diseases are a common cause of anal incontinence, whether central diseases (stroke, degenerative disease) and peripheral (the ponytail syndrome, peripheral neuropathy). The stretching pudendal neuropathy sometimes associated with falling perineum syndrome is a very common peripheral neurological cause of anal incontinence.
The main causes of the reduction of disturbances of the rectal perception are presented in Box 4.
Box 4. Disturbances of rectal perception
Neurological disorders
Dementia
Cerebrovascular accident
Tertiary syphilis
Multiple sclerosis
Brain tumors, spinal, medullary cone
Sensation Disorders
Overflow incontinence
Fecal impaction
Encopresis
Psychotropics, opiates
Antidiarrheal treatment
Rectocele
Traumatic anal incontinence:
Traumatic causes can be multiple, surgical, obstetric etiology accidental but is predominant.
The incidence of anal incontinence after a first delivery was indeed evaluated at 13%, but fortunately for the usually gas. These incontinence decreased quantitatively and qualitatively in the following months, but it is likely that successive traumatic childbirth can aggravate the table and manifest more fully in middle age.
The mechanisms of these postpartum anal incontinence are mixed, both nerve and muscle.
There is a stretching of the pudendal nerve (also called pudendal) during childbirth that can, with deliveries cessive juice cause irreversible nerve damage, determining a decrease in anal contraction (stretching neuropathy).
Muscle injuries have long been known as incontinence factors in case of perineal laceration stage III or IV despite perineal repair by the obstetrician after childbirth.
Advances in ultrasound endoanales explorations have shown that alongside these macroscopically visible tears, there were subclinical anal sphincter ruptures both external and internal, which play an important role in the genesis of later incontinence.
The risk factors of anal incontinence postpartum are the use of forceps during delivery, perineal tear, median episiotomy and working hours.
TREATMENT:
Several therapeutic options can be considered: drug approach, rehabilitative, surgical.
Drug approach:
It is common for fecal incontinence is revealed during transit disorders with liquid bowel movement more difficult to remember. The purpose of drugs is to try to regulate the transit slowing thereof and obtaining the stool of a higher viscosity. Loperamide, mucilage can fulfill this role. We must also fight against constipation: faecal stasis especially in the rectum being a source of seeps and incontinence.
Rehabilitative approach:
It is recognized that 70 to 80% of patients do not know how to use their perineal musculature. Voluntary movements of contraction and defecation must be relearned by patients. Motivation and patient participation are essential elements prognoses, not always easy to obtain in the very elderly.
To optimize this rehabilitation, biofeedback technique is to make the sphincter and pelvic floor muscle exercises under visual control which determines a quick decision by the patient aware of his muscular capacities. The results are often faster but maintaining improvement over time remains uncertain. The problem with this technique is the small number of motivated teams to support these patients.
Of electrostimulation techniques are most often proposed, for simpler implementation, but have no proven efficacy.
Surgical approach:
This approach has evolved in recent years as one of the alternatives was once only the discharge colectomy.
The new current techniques are still in an exploratory phase.
Direct repair:
If it is possible, is the best solution when there is a sphincter rupture, that it is obstetric, proctology or accidental.Success factors of this intervention are the localized nature of the breakdown and the absence of associated pudendal neuropathy.
Myorraphies:
They aim to tighten the muscle sphincter of the elements, especially the levator ani. The most common procedure is carried posterior myorrhaphy who can recreate a anorectal angle, an important element of continence. This intervention is indicated if the anal sphincter is intact but very functional. The results are average but the intervention has the advantage of simplicity.
Néosphincters:
If the external sphincter can not be repaired due to the complexity of the lesions, replace the sphincter.
There are two solutions:
– Electrostimulated graciloplasty: using a muscle of the thigh (gracilis muscle) technique described by Pickrell there forty years. The muscle is wrapped around the anus. The difficulty was to get a suitable contraction of this muscle.This technique which gives some good results has been updated by the use of electrical stimulators which allows better control of the opening and closing of muscular ring;
– The artificial sphincter can be opened or closed by a device that is inserted into the scrotum in men and in much lip in women. This is a silicone device whose opening and closing are thus controllable by the patient using a pump system. The results are mainly due to means infectious problems, related to the introduction of a foreign material.
CONCLUSION:
Anal incontinence is a public health problem largely undervalued due to reluctance of patients to talk to their doctor, the disorder being felt as demeaning.
The social impact can be very important and support depends on many pathophysiological mechanisms that may be involved, sometimes jointly. Methods for rehabilitations and new sphincter replacement techniques are still at an evaluation stage. A simple clinical assessment remains sufficient in many cases initially to guide treatment, unless serious sphincter lesion that occurs most often in a context postobstétrical or after surgery proctology.