Keywords

1 Introduction

Anal incontinence (AI) is the occurrence of an involuntary loss of gas or feces that strongly impairs patients’ quality of life. It affects individuals of all ages, races and gender; its overall prevalence in adults ranges from 11% to 15% and increases with age [1]. However, its real prevalence is probably underestimated as patients tend to avoid seeking medical care due to considerable embarrassment and stigma [2]. The manifestations of AI differ according to the severity of the condition, leading to a variety of heterogeneous clinical presentations, from the unintentional elimination of flatus or slight soilage, to the complete and unnoticed loss of feces. The mechanisms responsible for physiologic continence involve a complex interplay between stool consistency, compliance of the rectal reservoir, pelvic floor muscle groups, and proper functioning of the anal sphincter complex. Alterations in any of these elements—from stool consistency to muscular proficiency—may impact continence to flatus, liquid and solid stool and give rise to symptoms related to AI. It is known that the ideal stool consistency ranges between type 3 and 4 of the Bristol Stool Scale [3]. A change in stool consistency to the liquid pattern may impair continence even in the absence of sphincter lesions. Conversely, the presence of sphincter lesions or pelvic floor motility disorders may imply AI symptoms regardless of stool consistency. Alterations of the nervous system directly impairing the sampling reflex may also contribute to the occurrence of AI [4, 5]. AI may be also caused by the often-neglected functional alterations correlated to a thoraco-abdomino-perineal dyssynergia. The physiologic defecatory act in fact not only involves synchronism between the rectum and anus, but also requires correct thoraco-abdomino-perineal dynamics and vertebral position. Indeed, chest, abdomen, vertebral column and perineum are to be considered different parts of the same complex, all actively playing their role in patients with defecation disorders. Pelvic floor contraction and relaxation for physiologic defecation and urination depends on the harmonic integration of what can be schematized as the four sides of an “imaginary cuboid”: the diaphragm, the abdominal wall, the spine and the pelvic floor itself (Figs. 9.1 and 9.2) [6, 7]. For example, the correct movement of the diaphragm has a decisive role in increasing intra-abdominal pressure, a well-known and studied pattern of physiologic defecation [8]. AI severity depends on the type and frequency of episodes and, of course, on the extent to which the episodes affect the patients’ quality of life.

Fig. 9.1
An illustration of the factors behind pelvic floor rehabilitation. The factors include dyssynergies, costal breathing, hyperlordosis, alimentary behavior, muscular synergies, defecatory posture, postural disorders, toilet training, abdominal wall defects, and pelvic floor.

Pelvic floor dyssynergies, defecatory posture, postural disorders, alimentary behavior, pudendal neuropathy, and the correct interaction and equilibrium among all the structures belonging to the “imaginary cuboid” are all parameters to be evaluated to indicate pelvic floor rehabilitation, which aims at the functional correction of any altered physiatric parameters. (Reproduced from [6] with permission from Springer)

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Fig. 9.2
An illustration with 4 parts depicts the coordinated functioning of structures for the treatment of pelvic floor disorders. Parts a and b are labeled imaginary cuboids and c and d are inspiration and expiration. During inspiration, the abdomen expands and the perineum lowers. During expiration, the abdomen deflates and the perineum closes.

A brief representation of the interaction of the different structures forming the “imaginary cuboid”, whose correct functional interplay is the goal of pelvic floor rehabilitation and the necessary basis for treating pelvic floor disorders. (Reproduced from [7] with permission from Springer)

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2 Clinical Physiatric Evaluation

Routinely, the diagnostic algorithm for defecation disorders, such as AI, includes clinical tests (e.g., the Cleveland Clinic Incontinence Score), proctologic examination, radiologic imaging, instrumental tests (3D endorectal ultrasonography and high-resolution anorectal manometry), performed to assign patients an incontinence level [9,10,11]. Medical history should include previous anal surgery, hysterectomy, or previous vaginal deliveries; however, although these represent predictive factors of AI, they do not help to select patients amenable to pelvic floor rehabilitation nor do they provide any information predicting the effectiveness of the rehabilitative treatment. In this setting, it is important to extend the assessment of the proctological patient to include a clinical-physiatric evaluation [12] to be carried out alongside the clinical examinations and instrumental tests, consisting of:

  • Puborectalis contraction This parameter is useful to detect a paradoxical muscle contraction and an absent or incomplete relaxation.

  • Pubococcygeal test Phasic and tonic contraction can be evaluated by hooking a finger in the anal canal and asking the patient to contract the anus for the longest possible period of time [13, 14]. Incontinent patients show significantly worse pubococcygeal test than healthy controls.

  • Perineal defense reflex This evaluates the pelvic floor and abdominal muscle action following an increase in intra-abdominal pressure. The patient is asked to cough, so that the physician can observe and rate perineal muscle contraction as either a physiologic rising or a pathologic descending which, if marked, might be associated with emission of urine and flatulence [15,16,17]. The perineal defense reflex is evaluated as an expression of a correct thoraco-abdomino-perineal dynamics [16,17,18].

  • Muscular synergy The activity of both agonist (glutei and abductors) and antagonist (abdominals, diaphragm) muscles has to be evaluated with the patient in Sims’ position. The physician places a hand over the abdominal wall and observes the gluteal and abductor contraction as the patient is asked to contract the anus [15, 16]. In the case of a request for anal sphincter contraction, in fact, the recruitment of agonist muscles, such as the gluteus and abductor groups, can be caused by the patient’s incapacity to selectively recruit the correct muscles to comply with the request. Vice versa, the identification of antagonist muscles (abdominal muscles) during anal sphincter contraction also represents a conflict between the abdominal and perineal muscles [19]. A higher rate of agonist and antagonist muscle synergies has been noticed in incontinent patients.

  • Postural evaluation of lumbar lordosis The distance between the plumb line and the spinous process of L3 is measured, considering a range between 25 and 40 mm as normal [20]. In patients with severe lumbar hyperlordosis, the sacrum is positioned almost horizontally while the pelvic promontory is displaced dorsally and the coccyx ventrally [21]. According to its severity, lumbar lordosis may alter the orientation of the sacral promontory, the anorectal angle, and the puborectalis tone and consequently affect defecation.

  • Breathing dynamics During the first clinical examination it should be assessed whether or not the patient knows how to recruit the diaphragm and execute a correct breathing technique. In physiologic breathing, lowering of the diaphragm causes an increase in abdominal pressure, which is useful for the act of defecation. Regardless of the patient’s clinical presentation, the failure to recruit the diaphragm should be corrected through rehabilitation [22].

It is clear that a patient who might benefit from rehabilitation cannot be only clinically and instrumentally assessed: a physiatric assessment appears necessary, to enable the identification and correction of the altered parameters that modify the harmony of the “imaginary cuboid”. A proper and complete evaluation of physiatric parameters should therefore be included in every diagnostic protocol for incontinent patients [6, 7]. Only the finding of one or more altered physiatric parameters can justify the indication for pelvic floor rehabilitation, which is otherwise inappropriately prescribed. Correction of the altered parameters aims at reconstructing the physiologic harmony of the pelvic floor and the other structures forming the “imaginary cuboid”; this harmony is a necessary, though not always sufficient, condition for achieving clinical resolution of the symptoms. Only after improvement of function can we assess whether there is also clinical benefit. An inappropriate indication to rehabilitation not only leads to unnecessary treatment, but also fails to benefit the patient, and is responsible for incorrectly associating pelviperineal rehabilitation to a poor outcome.

3 Pelvic Floor Rehabilitation Treatment

3.1 The Re-Education Phase

A conservative therapeutic approach such as pelviperineal rehabilitation could be the first-line option when incontinence is associated with proven functional alterations.

What constitutes an ideal and complete pelvic floor rehabilitation treatment is a holistic management of the patient affected by AI, starting with a phase of re-education. The re-education.

program should be based on four mandatory points [7]:

  1. 1.

    Knowledge of anatomic-physiologic notions of the pelvic floor and defecation.

  2. 2.

    Awareness of the role of correct breathing and defecatory posture.

  3. 3.

    The importance of perception of the gastrocolic and gastroileal reflexes after an abundant meal without procrastinating the defecatory stimulus.

  4. 4.

    The great importance of consuming, in the right quantity and quality, the constituent elements of the feces (water, fiber, lactic acid bacteria).

More precisely, the re-education phase starts with providing the patient with correct information about ideal stool consistency and the diet to be followed to achieve it, as well as teaching the patient about the pelvic floor as an anatomic entity and its physiologic function. The pelvic floor is pierced by organs belonging to the sexual, urinary and defecatory systems, and it is useful, as well as desirable, for patients to have knowledge of its functioning [7]. Patients’ awareness of the anatomy and physiology of the district actively helps them to be part of the rehabilitation treatment. The clinical-physiatric approach and the re-educational phase aim to improve an altered bodily function; they are not merely cognitive steps, but they prepare the patient toward an active, rather than passive, role with deep participation during the healing process.

3.2 Pelvic Floor Rehabilitation “Tools”

Different pelvic floor rehabilitation techniques are used by the physician as different “tools”, depending on which physiatric parameter is found altered. Electric stimulation, for example, is a useful rehabilitation treatment for inducing consciousness of the anal area, a feature that may be as useful as the stimulation itself [23, 24].

A rehabilitation treatment should be based on different techniques specifically tailored to correct each functional alteration, and not applied as a standard undiscriminating recipe. Pelvic floor rehabilitation should in fact not only be identified with biofeedback alone, but should employ all of the different rehabilitation techniques:

  • External electrical stimulation helps patients to become aware of the perineal district [25] and to improve their muscular performance. An anal probe with a pulse generator is used to achieve adequate electrical stimulation, which has to be performed in cycles.

  • Biofeedback [26, 27] is performed using an electromyographic biofeedback system. Visual feedback is provided by observing changes in pressure activity on a monitor. Patients are taught to mainly practice contraction and relaxation of the anal canal, while evaluating the activity of the abdominal or gluteal/abductor muscles by using surface electromyography.

  • The principles of volumetric rehabilitation are based on the mechanical distension of the rectum [26, 27]. The aim of this technique is to restore impaired rectal sensation. The technique involves the twice daily administration of a tepid water enema. The goal of this rehabilitation technique is to help patients understand the three basic phases of the defecatory act (perception, retaining, passing), in order to become aware of the pelviperineal muscular activity.

  • Augmented self-perception and muscle reinforcement can be achieved by extracorporeal magnetic stimulation as well as electrostimulation, but magnetic stimulation is noninvasive and not embarrassing as patients do not have to be undressed while undergoing rehabilitation and do not need insertion of an anal plug (as in electric stimulation). The stimulation is provided by an electromagnetic generator in the seat of a chair where patients sit during the whole treatment session. Different studies had already assessed the effectiveness of extracorporeal magnetic stimulation in urinary incontinence [28], and in our experience it proved to be an effective treatment for idiopathic fecal incontinence [29].

  • Pelvic floor physical therapy, also referred to as pelvic floor muscle training, is a general term for the instruction of pelvic muscle strengthening, relaxation, and coordination exercises by a trained physical therapist [30] and comprises manipulations that have proven to be effective in reducing incontinence episodes, especially when associated with biofeedback [31].

3.3 Post-Rehabilitation Assessment

After the rehabilitation treatment, a follow-up clinical-physiatric evaluation should be carried out. The parameters found altered at the initial assessment and that supported the indication for pelvic floor rehabilitation should have been corrected by the treatment. This does not imply the clinical resolution of the symptoms but it represents the basis of a successful therapy, which will benefit from re-established harmony of the pelvic floor with the different sides of the “cuboid”.