Artificial sphincters (ASs) are used to replace the function of the biological sphincters in case of severe urinary and fecal incontinence (UI and FI), and gastroesophageal reflux disease (GERD). The design of ASs is established on different mechanisms, e.g., magnetic forces or hydraulic pressure, with the final goal to achieve a implantable and durable AS. In clinical practice, the implantation of in-commerce AS is considered a reasonable solution, despite the sub-optimal clinical outcomes. The failure of these surgeries is due to the malfunction of the devices (between 46 and 51%) or the side effects on the biological tissues (more than 38%), such as infection and atrophy. Concentrating on this latter characteristic, particular attention has been given to the interaction between the biological tissues and AS, pointing out the closing mechanism around the duct and the effect on the tissues. To analyze this aspect, an overview of existing commercial/ready-on-market ASs for GERD, UI, and FI, together with the clinical outcomes available from the in-commerce AS, is given. Moreover, this invited review discusses ongoing developments and future research pathways for creating novel ASs. The application of engineering principles and design concepts to medicine enhances the quality of healthcare and improves patient outcomes. In this context, computational methods represent an innovative solution in the design of ASs, proving data on the occlusive force and pressure necessary to guarantee occlusion and avoid tissue damage, considering the coupling between different device sizes and individual variability.

Fecal incontinence is a disabling condition affecting up to 20% of women.

We investigated fecal incontinence assessment in both inflammatory bowel disease and non-inflammatory bowel disease patients to propose a diagnostic approach for inflammatory bowel disease trials.

We searched on Pubmed, Embase and Cochrane Library for all studies on adult inflammatory bowel disease and non-inflammatory bowel disease patients reporting data on fecal incontinence assessment from January 2009 to December 2019.

In total, 328 studies were included; 306 studies enrolled non-inflammatory bowel disease patients and 22 studies enrolled inflammatory bowel disease patients. In non-inflammatory bowel disease trials the most used tools were the Wexner score, fecal incontinence quality of life questionnaire, Vaizey score and fecal incontinence severity index (in 187, 91, 62 and 33 studies). Anal manometry was adopted in 41.2% and endoanal ultrasonography in 34.0% of the studies. In 142 studies (46.4%) fecal incontinence evaluation was performed with a single instrument, while in 64 (20.9%) and 100 (32.7%) studies two or more instruments were used. In inflammatory bowel disease studies the Wexner score, Vaizey score and inflammatory bowel disease quality of life questionnaire were the most commonly adopted tools (in five (22.7%), five (22.7%) and four (18.2%) studies). Anal manometry and endoanal ultrasonography were performed in 45.4% and 18.2% of the studies.

Based on prior validation and experience, we propose to use the Wexner score as the first step for fecal incontinence assessment in inflammatory bowel disease trials. Anal manometry and/or endoanal ultrasonography should be taken into account in the case of positive questionnaires.

No systematic review has examined the collective randomized and nonrandomized evidence for fecal incontinence treatment effectiveness across the range of surgical treatments.

The purpose of this study was to assess the efficacy, comparative effectiveness, and harms of surgical treatments for fecal incontinence in adults.

Ovid MEDLINE, EMBASE, Physiotherapy Evidence Database, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine, and the Cochrane Central Register of Controlled Trials, as well as hand searches of systematic reviews, were used as data sources.

Two investigators screened abstracts for eligibility (surgical treatment of fecal incontinence in adults, published 1980-2015, randomized controlled trial or observational study with comparator; case series were included for adverse effects). Full-text articles were reviewed for patient-reported outcomes. We extracted data, assessed study risk of bias, and evaluated strength of evidence for each treatment-outcome combination.

Surgical treatments for fecal incontinence were included interventions.

Fecal incontinence episodes/severity, quality of life, urgency, and pain were measured.

Twenty-two studies met inclusion criteria (13 randomized trials and 9 observational trials); 53 case series were included for harms. Most patients were middle-aged women with mixed FI etiologies. Intervention and outcome heterogeneity precluded meta-analysis. Evidence was insufficient for all of the surgical comparisons. Few studies examined the same comparisons; no studies were high quality. Functional improvements varied; some authors excluded those patients with complications or lost to follow-up from analyses. Complications ranged from minor to major (infection, bowel obstruction, perforation, and fistula) and were most frequent after the artificial bowel sphincter (22%-100%). Major surgical complications often required reoperation; few required permanent colostomy.

Most evidence is intermediate term, with small patient samples and substantial methodologic limitations.

Evidence was insufficient to support clinical or policy decisions for any surgical treatments for fecal incontinence in adults. More invasive surgical procedures had substantial complications. The lack of compliance with study reporting standards is a modifiable impediment in the field. Future studies should focus on longer-term outcomes and attempt to identify subgroups of adults who might benefit from specific procedures.

Antegrade continence enema is a proximal colonic stoma that allows antegrade lavage of the colon for the treatment of fecal incontinence and functional constipation. Its role in the treatment of these conditions in adults has not been established.

This review aimed to evaluate the clinical response and complications of antegrade continence enema in the adult population.

A systematic literature search of MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases from January 1980 to October 2013 was conducted.

Studies reporting clinical outcomes of antegrade continence enema in adult patients were considered. Only studies with participants aged 16 years and older were selected.

Use of the antegrade continence enema for the treatment of constipation and incontinence in adults was investigated.

The primary outcome was the number of patients irrigating their stoma. Secondary outcomes included the incidence of stoma stenosis, assessment of functional outcome, and evaluation of quality of life.

Overall, 15 studies were selected, describing outcomes in 374 patients. All of the reports were observational cross-sectional studies, and 4 were prospective. The number of participants still using their stoma ranged from 47% to 100% over a follow-up period of 6 to 55 months. Eleven studies reported achievement of full continence in 33% to 100% of patients. Four studies described functional outcomes, and 7 studies reported a wide range of patient satisfaction. The rate of stoma stenosis varied from 8% to 50%.

There were considerable heterogeneities within and across studies. Most studies were of poor quality, as reflected in the Methodological Index for Nonrandomized Studies score.

Antegrade continence enema has been reported as an acceptable treatment of both functional constipation and fecal incontinence in adults across several analyses. There is wide variation regarding outcome measures. Larger prospective studies are required to assess the role of antegrade continence enema in the adult population.

Fecal incontinence (FI) is a multifactorial disorder that imposes considerable social and economic burdens. The aim of this article is to provide an overview of current and emerging treatment options for FI. A MEDLINE search was conducted for English-language articles related to FI prevalence, etiology, diagnosis, and treatment published from January 1, 1990 through June 1, 2013. The search was extended to unpublished trials on ClinicalTrials.gov and relevant publications cited in included articles. Conservative approaches, including dietary modifications, medications, muscle-strengthening exercises, and biofeedback, have been shown to provide short-term benefits. Transcutaneous electrical stimulation was considered ineffective in a randomized clinical trial. Unlike initial studies, sacral nerve stimulation has shown reasonable short-term effectiveness and some complications. Dynamic graciloplasty and artificial sphincter and bowel devices lack randomized controlled trials and have shown inconsistent results and high rates of explantation. Of injectable bulking agents, dextranomer microspheres in non-animal stabilized hyaluronic acid (NASHA Dx) has shown significant improvement in incontinence scores and frequency of incontinence episodes, with generally mild adverse effects. For the treatment of FI, conservative measures and biofeedback therapy are modestly effective. When conservative therapies are ineffective, invasive procedures, including sacral nerve stimulation, may be considered, but they are associated with complications and lack randomized, controlled trials. Bulking agents may be an appropriate alternative therapy to consider before more aggressive therapies in patients who fail conservative therapies.

Fecal incontinence is a frequent and debilitating condition that may result from a multitude of different causes. Treatment is often challenging and needs to be individualized. During the last several years, new technologies have been developed, and others are emerging from clinical trials to commercialization. Although their specific roles in the management of fecal incontinence have not yet been completely defined, surgeons have access to them and patients may request them. The purpose of this project is to put into perspective, for both the patient and the practitioner, the relative positions of new and emerging technologies in order to propose a treatment algorithm.

This paper proposes a novel artificial anal sphincter system (AASS) for severe fecal incontinence. The AASS is composed of an artificial anal sphincter (AAS), an external transcutaneous energy transmission system (TETS), and an external control device. The AAS is composed of a cuff, a micropump, a reservoir, and a remote control device. It is designed to be implanted into the body of the patient. The function of the AAS is to open and close the patient's natural anus. Patients suffering from loss of their natural sphincter lose rectal sensation and are thus unable to perceive imminent fecal incontinence. In order to restore rectal sensation, a pressure sensor in the AAS cuff is designed to detect pressure in the colon. The pressure reflects the present quantity of colon contents, allowing patients to control the AAS to open or close the anus according to the pressure. The TETS is designed to provide electrical energy to the implanted AAS without wire connections. The external control device is designed to receive the pressure information from the AAS and send the patient's command to the implanted device. This paper provides a thorough discussion of the design of the novel AASS and describes the performance of the AASS when tested in vivo on two Beagle dogs who were chosen to be the subjects for receiving the implant. The experimental results verified that the performance of the AASS met the functional requirements it was designed for; however, the trial also revealed some challenges to be further studied.

Fecal incontinence is a disabling symptom with medical and social implications, including fear, embarrassment, isolation and even depression. Most patients live in seclusion and have to plan their life around the symptom, with secondary impairment of their quality of life. Conservative management and biofeedback therapy are reported to benefit a good percentage of those affected. However, surgery must be considered in the non-responder population. Recently, sacral nerve electrostimulation, lately named neuromodulation, has been reported to benefit patients with fecal incontinence in randomized controlled trials more than placebo stimulation and conservative management, by some unknown mechanism. Neuromodulation is a minimally invasive procedure with a low rate of adverse events and apparently favorable cost-efficacy profile. This review is intended to expand knowledge about this effective intervention among the non-surgically skilled community who deals with this disabled group of patients.

Fecal incontinence (FI) remains a socially isolating condition with profound impact on quality of life for which autologous myoblast cell therapy represents an attractive treatment option. We developed an animal model of FI and investigated the possibility of improving sphincter function by intrasphincteric injection of syngeneic myoblasts. Several types of anal cryoinjuries were evaluated on anesthetized Fischer rats receiving analgesics. The minimal lesion yielding sustainable anal sphincter deficiency was a 90° cryoinjury of the sphincter, repeated after a 24-h interval. Anal sphincter pressure was evaluated longitudinally by anorectal manometry under local electrostimulation. Myoblasts were prepared using a protocol mimicking a clinical-grade process and further transduced with a GFP-encoding lentiviral vector before intrasphincteric injection. Experimental groups were uninjured controls, cryoinjured + PBS, and cryoinjured + myoblasts (different doses or injection site). Myoblast injection was well tolerated. Transferred myoblasts expressing GFP integrated into the sphincter and differentiated in situ into dystrophin-positive mature myofibers. Posttreatment sphincter pressures increased over time. At day 60, pressures in the treated group were significantly higher than those of PBS-injected controls and not significantly different from those of normal rats. Longitudinal follow-up showed stability of the therapeutic effect on sphincter function over a period of 6 months. Intrasphincteric myoblast injections at the lesion borders were equally as effective as intralesion administration, but an injection opposite to the lesion was not. These results provide proof of principle for myoblast cell therapy to treat FI in a rat model. This strategy is currently being evaluated in humans in a randomized double-blind placebo-controlled clinical trial.

Fecal incontinence is a common and severely disabling disorder. For patients with severe fecal incontinence, surgery may prove to be the only adequate treatment option.

This study reports on 43 patients that were treated with a prosthetic sphincter system between 2005 and 2009 in three coloproctological centres.

complications, anal pressures before and after surgery, fecal continence score.

The new artificial sphincter system significantly improves continence but leads to some complications in clinical practice. After implantation of the device, continence improved significantly (Keller & Jostarndt continence score 2.6 to 14.3 (P < 0.01)). With the band activated, resting pressure improved significantly as compared to baseline (10.7 mmHg vs. 66.1 mm Hg, P < 0.01). The same holds for anal sphincter squeeze pressure (32.2 mmHg versus 85.9 mm Hg, P < 0.01). Complications occurred in 21 patients (48.8%): 10 surgical and 13 technical. Two patients were affected by both technical and surgical problems. The median time of the occurrence was 3 months postop. In five patients difficulties arose within the first postoperative month leading to explantation of the device in three patients. 90% of complications occurred in the first year.

The soft anal band of AMI (AAS), a new artificial anal sphincter, improves severe anal incontinence, but it must be regarded as a last treatment option to avoid a stoma.

Fecal incontinence is a socially devastating problem that can be cured by the artificial bowel sphincter in selected cases.

This study evaluates short- and long-term morbidity and functional results of the artificial bowel sphincter.

This study is a retrospective evaluation of consecutive patients.

This study was conducted at 2 academic colorectal units.

Between May 2003 and July 2010, all consecutive patients who underwent artificial bowel sphincter implantation for severe fecal incontinence were included in the study.

The artificial bowel sphincter was implanted through 2 incisions made in the perineum and suprapubic area.

Patients were reviewed at months 1, 6, and 12, and then annually. Mortality, morbidity (early infection within the first 30 days after implant, and late thereafter), and reoperations including explantations were analyzed. Anal continence was evaluated by means of the Cleveland Clinic Florida score. Mean follow-up was 38 months (range, 12-98).

Between May 2003 and July 2010, 21 consecutive patients with a mean age of 51 years (range, 23-71) underwent surgery. There was no mortality. All patients presented with at least 1 complication. Infection or cutaneous ulceration occurred in 76% of patients, perineal pain in 29%, and rectal evacuation disorders in 38%. The artificial bowel sphincter was definitely explanted from 17 patients (81%). The artificial sphincter was able to be activated in 17 patients (81%), and continence was satisfactory at 1 year in those who still had their sphincter in place (n = 12).

There is a very high rate of morbidity and explantation after implantation of an artificial bowel sphincter for fecal incontinence. Four of 21 patients who still had an artificial sphincter in place had satisfactory continence at a mean follow-up of 38 months.

The aim of this study was to evaluate the short- and long-term outcome of the radiofrequency treatment for moderate to severe fecal incontinence.

This study is a retrospective review of a single-institution experience.

Patients who underwent the radiofrequency procedure were included.

The primary outcomes measured were the complication rate, short- and long-term response, and the rate of subsequent intervention for incontinence.

Twenty-seven patients underwent 31 radiofrequency procedures (81% women; mean age, 64 years). Median length of symptoms was 3 years. Biofeedback had failed for 52% of patients, and 23% of patients had previous surgical intervention. Thirty-eight percent of patients had a sphincter defect. Minor complications were observed in 19% of the patients. A treatment response was noted in 78% of the patients (mean Cleveland Clinic Florida Fecal Incontinence Score: 16 (baseline) and 10.9 (3 months postoperatively)). However, a sustained long-term response without any additional intervention was noted in 22% of the patients, and 52% of the patients underwent or are awaiting additional intervention for persistent or recurrent incontinence (mean follow-up, 40 months).

This study is limited by its retrospective nature and the limited number of subjects.

The radiofrequency procedure was safe, but a long-term benefit was noted in a minority of patients with moderate to severe fecal incontinence. Additional interventions were required in more than half of the patients. Larger studies are needed to determine the impact of various patient-related factors on the outcome of the radiofrequency treatment to identify the ideal patient for this therapy.

Faecal incontinence is a significant source of distress, and a permanent stoma is frequently offered to these patients. The antegrade colonic enema (ACE) procedure is an alternative approach to treat faecal incontinence. The long-term outcome remains unknown in adults with faecal incontinence. The aim of this study was to evaluate the long-term results of the ACE procedure for incontinence in adults and its impact upon quality of life.

All patients who underwent an ACE procedure between 1999 and 2009 were included. Clinical and demographic data and postoperative course were obtained from a review of medical records and databases. Each patient underwent a telephone interview. Quality of life was assessed using the GIQLI and SF36 scores, and faecal incontinence was evaluated using the Wexner score.

Seventy-five patients (54 females; 72%) were included. An ileal neoappendicostomy was performed in 68 patients (90%). The mean hospital stay was 9 days (range 6-24 days). Early complications occurred in four patients and late surgical complications (after 3 months) were observed in 12 (16%) patients. At a median follow up of 48 months, 64 (91%) were still performing enemas, and treatment was judged to be successful in 55 (86%) of 64 patients. The Wexner score was 3.4 ± 2.4, showing a significant reduction when compared with the preoperative value (P < 0.0001). Quality of life scores were in the range of a control population.

The ACE procedure is an effective long-term strategy in the treatment of faecal incontinence, with low and acceptable morbidity, and should be preferred before definitive colostomy.