Novel insights into physiological mechanisms underlying fecal continence

The machinery maintaining fecal continence prevents involuntary loss of stool and is based on the synchronized interplay of multiple voluntary and involuntary mechanisms, dependent on cooperation between motor responses of the musculature of the colon, pelvic floor, and anorectum, and sensory and motor neural pathways. Knowledge of the physiology of fecal continence is key toward understanding the pathophysiology of fecal incontinence. The idea that involuntary contraction of the internal anal sphincter is the primary mechanism of continence and that the external anal sphincter supports continence only by voluntary contraction is outdated. Other mechanisms have come to the forefront, and they have significantly changed viewpoints on the mechanisms of continence and incontinence. For instance, involuntary contractions of the external anal sphincter, the puborectal muscle, and the sphincter of O'Beirne have been proven to play a role in fecal continence. Also, retrograde propagating cyclic motor patterns in the sigmoid and rectum promote retrograde transit to prevent the continuous flow of content into the anal canal. With this review, we aim to give an overview of primary and secondary mechanisms controlling fecal continence and evaluate the strength of evidence.

The Most Common Functional Disorders and Factors Affecting Female Pelvic Floor

The pelvic floor (PF) is made of muscles, ligaments, and fascia, which ensure organ statics, maintain muscle tone, and are involved in contractions. This review describes the myofascial relationships of PF with other parts of the body that determine the proper functions of PF, and also provides insight into PF disorders and the factors contributing to them. PF plays an important role in continence, pelvic support, micturition, defecation, sexual function, childbirth, and locomotion, as well as in stabilizing body posture and breathing, and cooperates with the diaphragm and postural muscles. In addition, PF associates with distant parts of the body, such as the feet and neck, through myofascial connections. Due to tissue continuity, functional disorders of muscles, ligaments, and fascia, even in the areas that are distant from PF, will lead to PF disorders, including urinary incontinence, fecal incontinence, prolapse, sexual dysfunction, and pain. Dysfunctions of PF will also affect the rest of the body.

Composite Antropyloric Valve and Gluteus Maximus Muscle Wrap for Neoanal Reconstruction: Initial Results

BACKGROUND

Severe fecal incontinence has a significant negative impact on patient well-being. Current surgical methods of total anorectal reconstruction to substitute a colostomy have suboptimal results. A composite graft using antropyloric valve transposition and gracilis wrap has been described with good outcomes. However, this procedure requires extensive training of patients. Gluteus maximus, an accessory muscle for continence, may be better suited for this purpose.

OBJECTIVE

The purpose of this study was to evaluate the outcomes of composite antropylorus-gluteus graft for intractable fecal incontinence.

DESIGN

Patients underwent a 3-stage procedure: antropyloric transposition with diversion stoma followed by gluteus wrap. Stoma was closed after ensuring the anatomic and functional integrity of the graft.

SETTINGS

This study was conducted at a single tertiary care institution.

PATIENTS

Patients who were on permanent colostomy for intractable incontinence or would have had one after abdominoperineal resection were included.

MAIN OUTCOME MEASURES

Endoultrasonography, MRI, loopogram, saline holding test, anal manometry, St. Mark's fecal incontinence score, and personal interviews were used for measurement.

RESULTS

Eleven patients underwent the procedure with a median follow-up of 16 months (range, 13-34 mo). Digital rectal examination revealed a resting tone with a distinct squeeze provided by the composite graft. Radiological imaging confirmed healthy grafts. There was a significant improvement in mean anal manometry values (resting pressure: preoperative = 10.25 mm Hg vs postoperative = 20.45 mm Hg; squeeze pressure: preoperative = 22.63 mm Hg vs postoperative = 105.18 mm Hg) and mean incontinence score postprocedure (preoperative = 22.8 vs postoperative = 8.6). On personal interview, majority of the patients were continent and expressed satisfaction with the procedure.

LIMITATIONS

The study was limited by its small sample size with no control group.

CONCLUSIONS

Composite graft in patients with intractable fecal incontinence can serve as a viable novel method for total anorectal reconstruction. However, it should only be recommended for a highly select group of individuals in a surveillance setting. Its long-term outcomes remain to be determined as well as its risk versus benefit.

Effect of abdominal drawing-in maneuver during hip extension on the muscle onset time of gluteus maximus, hamstring, and lumbar erector spinae in subjects with hyperlordotic lumbar angle

Background

The abdominal drawing-in maneuver (ADIM) is used to prevent abnormal movements of the lumbar spine and pelvis during therapeutic exercises. This study compared the effects of ADIM on the muscle onset time of the hamstring, gluteus maximus, and erector spinae muscles during prone hip extension exercise in subjects with or without hyperlordotic lumbar angle. Forty healthy adults (18 male, 22 female) were recruited for this study.

Methods

The lumbar lordotic angles and pelvic tilt angles of the subjects were measured using the Avaliação postural analysis software. The subjects were divided into two groups: the lumbar hyperlordotic angle (LHLA) and lumbar normal lordotic angle (LNLA) groups. The muscle contraction onset time of the hamstring, gluteus maximus, and erector spinae were assessed using surface electromyography.

Results

During ADIM application, the muscle contraction onset time of the gluteus maximus was significantly increased in the LHLA group compared with the LNLA group.

Conclusions

ADIM application during prone hip extension was more effective for gluteus maximus onset time in the LHLA group. Therefore, ADIM during prone hip extension may be useful for gluteus maximus training in individuals with lumbar hyperlordosis.

The effect of pelvic physiotherapy on reduction of functional constipation in children: design of a multicentre randomised controlled trial

Background

Functional constipation is a common disorder worldwide and is found in all paediatric age groups. Functional constipation can be caused by delayed colonic transit or dysfunction of the pelvic floor muscles. Standard medical care in paediatric practice is often based on clinical experience and mainly consists of a behavioural approach and toilet training, along with the prescription of laxatives. Evidence to evaluate the effectiveness of pelvic physiotherapy for this complaint is lacking.

Methods/design

A two-armed multicentre randomised controlled trial has been designed. We hypothesise that the combination of pelvic physiotherapy and standard medical care will be more effective than standard medical care alone for constipated children, aged 5 to 17 years. Children with functional constipation according to the Rome III will be included. Web-based baseline and follow-up measurements, scheduled at 3 and 6 months after inclusion, consist of the numeric rating scale in relation to the perceived severity of the problem, the Strength and Difficulties Questionnaire and subjective improvement post-intervention (global perceived effect). Examination of the pelvic floor muscle functions, including digital testing and biofeedback, will take place during baseline and follow-up measurements at the physiotherapist. The control group will only receive standard medical care, involving at least three contacts during five months, whereas the experimental group will receive standard medical care plus pelvic physiotherapy, with a maximum of six contacts. The physiotherapy intervention will include standard medical care, pelvic floor muscle training, attention to breathing, relaxation and awareness of body and posture. The study duration will be six months from randomisation, with a three-year recruitment period. The primary outcome is the absence of functional constipation according to the Rome III criteria.

Discussion

This section discusses the relevance of publishing the study design and the development of the presented physiotherapy protocol. It also addresses difficulties when interpreting the literature with regard to the effectiveness of biofeedback, potential confounding, and future research indications. To our knowledge, this article is the first to describe the design of a randomised controlled trial among children with constipation to assess the effect of pelvic physiotherapy as an add-on to standard medical care.

Trial registration

Current Controlled Trials NL30551.068.09

Functional interactions between the fossa ischioanalis, levator ani and gluteus maximus muscles of the female pelvic floor: a prospective study in nulliparous women

PURPOSE

We evaluated the role of the fossa ischioanalis (FI) in functional relations between the levator ani (LA) and gluteus maximus muscles (GM) in healthy female volunteers.

METHODS

Twenty-three nulliparae were examined. Electromyogramms of LA and GM were simultaneously recorded during voluntary contraction of the pelvic floor muscles (PFM) and at rest in six body positions. The surface areas of LA (LAA), FI (FIA) and GM (GMA) were evaluated using MRI.

RESULTS

Simultaneous LA and GM contractions were electromyographically observed irrespectively of body position in 97.2 %. MRI revealed synchronous movement of all structures: while LAA (-7.4 %) reduced, GMA increased (+6.8 %), FIA changed significantly (+3.4 %).

CONCLUSIONS

The LA, FI and GM are morphologically and functionally connected. We recommend considering these structures as the 'LFG-Complex', emphasising the importance of this unit for functional integration of the pelvic floor. The findings of this study may contribute to understanding of urinary continence mechanism and disorders after pelvic floor surgery and obstetrical trauma.