Challenges faced in the clinical application of artificial anal sphincters

Abstract

Fecal incontinence is an unresolved problem, which has a serious effect on patients, both physically and psychologically. For patients with severe symptoms, treatment with an artificial anal sphincter could be a potential option to restore continence. Currently, the Acticon Neosphincter is the only device certified by the US Food and Drug Administration. In this paper, the clinical safety and efficacy of the Acticon Neosphincter are evaluated and discussed. Furthermore, some other key studies on artificial anal sphincters are presented and summarized. In particular, this paper highlights that the crucial problem in this technology is to maintain long-term biomechanical compatibility between implants and surrounding tissues. Compatibility is affected by changes in both the morphology and mechanical properties of the tissues surrounding the implants. A new approach for enhancing the long-term biomechanical compatibility of implantable artificial sphincters is proposed based on the use of smart materials.

Keywords: Artificial anal sphincter (AAS); Biomechanical compatibility; Fecal incontinence (FI); Smart materials.

Conflict of interest statement

Compliance with ethics guidelines: Ming-hui WANG, Ying ZHOU, Shuang ZHAO, and Yun LUO declare that they have no conflict of interest.

This article does not contain any studies with human or animal subjects performed by any of the authors.

Figures

Fig. 1

Acticon Neosphincter American Medical Systems, Inc., Minnetonka, MN, USA (https://pelvichealthsource.com/content/dam/wph/us-region/en/documents/labeling/fecal-incontinence/1006168.r03_ORMan_Acticon_en.pdf)

Fig. 2

German artificial sphincter system (a) and Modified prosthesis design (b) (a) Reprinted from ref. (Doll et al., 2006), Copyright 2005, with permission from Elsevier; (b) Reproduced from ref. (Ruthmann et al., 2010) by permission of John Wiley and Sons

Fig. 3

Pillow-type prosthetic anal sphincter Reproduced from ref. (Finlay et al., 2004) by permission of John Wiley and Sons

Fig. 4

Structure of AAS Reprinted from ref. (Zan et al., 2008) with permission from Zhejiang University and Springer-Verlag GmBH

Fig. 5

Novel artificial sphincter using shape memory alloys and transcutaneous energy transmission technologies Reprinted from ref. (Luo et al., 2006) by permission of Taylor & Francis (http://www.tandfonline.com)