Archived Policies - Surgery

Plugs for Fistula Repair


Effective Date:08-15-2011

End Date:12-31-2013


Biosynthetic fistula plugs, including plugs made of porcine small intestine submucosa or of synthetic material, are considered experimental, investigational and unproven for all indications including, but not limited to, repair of anal and rectal fistulas.


A fistula is an abnormal communication between one surface in the body that connects to another.  Fistulas can occur at different places in the body, the most common being anal.  Rarer forms may communicate with the vagina (rectovaginal fistula), other pelvic structures, the bowel (enterocutaneous), or tracheoesophageal.

An anal fistula occurs between the interior of the anal canal or rectum and the skin surface.  Most fistulas begin as anorectal abscesses.  When the abscess opens spontaneously into the anal canal (or has been opened surgically), a fistula may occur.  Other causes of fistulas include tuberculosis, cancer, and inflammatory bowel disease.  Fistulas may occur singly or in multiples. Symptoms include a purulent discharge and drainage of pus and/or stool near the anus, which can irritate the outer tissues causing itching and discomfort.  Pain occurs when fistulas become blocked and abscesses recur.  Flatus may also escape from the fistulous tract.  Anal fistulas are described as low (present in the lower part and not extending up to the anorectal sling) or high (extending up to or beyond the anorectal sling).  High fistula can be associated with incontinence.  Diagnosis may involve fistula probe, anoscopy, fistulography, ultrasound, or magnetic resonance imaging.  Treatment is aimed at repairing the fistula without compromising continence.  Treatments include fistulotomy/fistulectomy, endorectal/anal sliding flaps, seton drain, and fibrin glue.  Lay-open fistulotomy in high fistulas carries risk of incontinence.  Draining setons can control sepsis but few patients heal after removal of the seton, and they are poorly tolerated long term.  Cutting setons can cause continence disturbances.

A rectovaginal fistula occurs between the rectum and the vagina.  It may result from trauma (including operative, obstetric, and traumatic injuries), infection, inflammatory bowel disease (Chron’s) , carcinoma, and radiation.  Symptoms include passage of gas or stool from vagina, recurrent vaginal infection, and foul-smelling vaginal discharge.  Diagnosis may involve ultrasound, water and blue dye tests, vaginogram, barium enema, cat scan, or magnetic resonance imaging. Treatment is surgical repair and may include a transanal endorectal advancement flap, fibrin glue, and depending upon severity and cause, even a proctectomy.

Enterocutaneous fistulas (ECFs) occur between the small or large bowel and the skin, and some definitions include other areas of the gastrointestinal (GI) tract.  ECFs can occur due to surgical complications of the GI tract, cancer, radiation, inflammatory bowel disease, diverticulitis, infections, or ischemic conditions.  Management is individualized due to complexity and size, however, treatment focuses on hydration, antibiotics, nutritional support, skin protection and fistula drainage.

Biosynthetic fistula plugs are devices proposed to promote healing and prevent recurrence of  fistula.  The conical-shaped plug is anchored in the fistula and acts as a scaffold into which new tissue can grow to close the fistula.  The plug is absorbed into the body in six to eight weeks.  The procedure may require 12–24 hours observation postoperatively.  The procedure can be repeated in case of failure.

  • The SIS Fistula Plug (Cook Biotech) received 510(k) clearance from the U.S. Food and Drug Administration (FDA) in March 2005 based on predicate devices, including the SURGISIS® Soft Tissue Graft and the STRATASIS® Urethral Sling, both manufactured by Cook Biotech Incorporated.  The SIS Fistula Plug is manufactured from porcine small intestinal submucosa (SIS) “for implantation to reinforce soft tissue where a rolled configuration is required, for repair of anal, rectal, and enterocutaneous fistulas”.  
  • The modified SIS Fistula Plug, also manufactured from porcine small intestinal submucosa (SIS), is supplied in a tapered configuration with a button to provide increased retention of the plug and improved blockage of the fistula.  The SIS Fistula Plug received 510(k) clearance in October 2006.  
  • In February 2009, Cook Biotech received 510(k) clearance from the FDA for Surgisis® Biodesign™ Enterocutaneous Fistula Plug based on predicate devices, including the SURGISIS® Soft Tissue Graft and the STRATASIS® Urethral Sling, both manufactured by Cook Biotech Incorporated.  The plug is manufactured from porcine small intestinal submucosa and the indications of use are “for implantation to reinforce soft tissue for repair of enterocutaneous fistulas”.
  • In March 2009, W.L. Gore & Associates received 510(k) clearance for the BIO-A® Fistula Plug intended for use in anorectal fistulas.  The GORE BIO-A Fistula Plug device comprises a porous structure of synthetic bioabsorbable PGA/TMC copolymer fiber, degraded via a combination of hydrolytic and enzymatic pathways, the same material, technology, and three-dimensional disk with tubes mesh design as the predicate GORE Bioabsorbable Mesh hernia plug device.  The indications for use and performance of the GORE BIO-A™ Fistula Plug are substantially equivalent to the predicate Cook SIS Fistula Plug.


There is limited published data on outcomes of fistula plug procedures, and in all of the published studies, fistula plugs were made of porcine small intestinal submucosal tissue.  A search of the peer-reviewed literature found one randomized controlled trial and three retrospective comparative studies.  

Ortiz and colleagues in a European trial compared use of porcine submucosal (Surgisis) anal fistula plug (AFP) with an endorectal anal flap (ERAF) procedure in a randomized controlled trial (RCT) with 43 patients who had high anal fistula.  The primary endpoint was fistula healing. Recurrence was defined as the presence of an abscess in the same area or obvious evidence of fistulization.  Five patients in the AFP group and six in the ERAF group did not receive the allocated intervention, leaving 32 patients.  One patient in the AFP group was lost to follow-up. A large number of recurrences in the fistula plug group led to premature closure of the trial.  After one-year, fistula recurrence was seen in 12 of 15 patients treated with an anal fistula plug versus two of 16 patients who underwent the flap procedure (relative risk 6.40 [95% confidence interval {CI} 1.70-23.97]); p<0.001).  Fistulas recurred in 9 of 16 patients who had previously undergone fistula surgery; 8 of the 9 patients had an AFP. A trend for more sphincter involvement and more females in the ERAF group was noted. Complications were not reported in this paper.

Christoforidis et al. performed a retrospective analysis of patients from a U.S. center with transsphincteric fistulas treated with ERAF (n=43) or anal plug (Surgisis) (n=37) between January 1996 and April 2007.  Success was defined as closed external opening in absence of symptoms at minimal follow-up of six months.  The success rate was 63% in the ERAF group and 32% in the in AFP group after a mean follow-up of 56 (range, 6–136) months for ERAF and 14 (range, 6–22) months.  After exclusion of patients with early AFP extrusion, which may by considered a technical failure, the ERAF advantage did not meet statistical significance (p=0.06). Twenty-three of 27 patients who had ERAF and seven of 12 patients who had AFP responded to a questionnaire addressing functional outcomes.  In the ERAF group 11 of 23 patients had no continence disturbance versus six of seven in the AFP group.  The lack of prospectively collected incontinence scores prior to the procedure and low response rate in the AFP group prohibit valid comparisons on functional outcomes.  Complication rates were low in both groups; two patients in the ERAF group required reoperation for bleeding.  No serious complications occurred in the AFP group.  The authors conclude that “randomized trials are needed to further elucidate the efficacy and potential functional benefit of AFP in the treatment of complex anal fistulas.”

Wang et al. compared outcomes of all patients with transsphincteric fistulas treated with AFP from July 2005 to December 2006 (n=29) and compared them with historical controls treated with ERAF (2001–2005) (n=26).  Of 26 initial flap procedures, 10 failed and 16 healed.  Of 29 initial plug procedures, 19 failed and 10 healed.  In total, 30 advancement flaps and 34 plug procedures were performed (including the additional treatments for failed initial procedures). Closure rates were 34% for plugs (mean follow-up 279 [range, 110–690] days) and 62% for flaps (median follow-up 819 [range, 93–1928] days; p=0.045).  Complications were not reported.  The authors conclude that a systematic randomized trial with long-term follow-up comparing advancement flaps with fistula plugs is needed, and they calculate that 112 patients would need to be randomized to detect a statistically significant difference in success rates for each procedure.  Because the fistula plugs are costly, the authors recommend that cost-benefit analysis be performed.

A retrospective study of 232 patients treated in Canada between 1997 and 2008 by a variety of methods for high transsphincteric anal fistulas was reported by Chung et al.  Postoperative healing rates at the 12-week follow-up for the fistula plug, fibrin glue, flap advancement, and seton drain groups were 59.3%, 39.1%, 60.4%, and 32.6%, respectively.  They conclude that closure of the primary fistula opening using a biological anal fistula plug and anal flap advancement result in similar fistula healing rates in patients with high transsphincteric fistulas, and that these strategies are superior to seton placement and fibrin glue.  “Given the low morbidity and relative simplicity of the procedure, the anal fistula plug is a viable alternative treatment for patients with high transsphincteric anal fistulas.”  The 12-week follow-up time in this study is likely too short to evaluate the durability of treatment.

The remainder of the published evidence for anal fistula plug consists of case series, most with small numbers of subjects.  A 2009 systematic review by Garg reports a wide range of success rates.  In the 12 included studies, all case series, reported success rates for the AFP procedure were from 24% to 92%.  Success rates in treating complex fistula-in-ano in the eight prospective studies reviewed were 35%–87%.

Other papers report treatment of very small numbers of patients with rectovaginal fistulas, endoscopic treatment of postoperative enterocutaneous fistulas after bariatric surgery, a colocutaneous fistula, and a recurrent tracheoesophageal fistula treated with fistula plug.  In 2007 Ballie et al. reported on eight case reports involving 137 patients that underwent bioprosthetic material to facilitate complex abdominal wall reconstruction, including one for enterocutaneous fistula.  The authors’ conclusions were that prospective randomized controlled studies were needed to compare the safety and effectiveness of other techniques as well as porcine bioprostheses.   

A number of clinical trials are proposed or recruiting patients, including a study in which 300 patients will be randomized to receive either the Surgisis plug or placement of a cutting seton drain, and an industry-sponsored study comparing the Surgisis plug with advancement flap surgery.  

The most recent (2005) Practice Parameters for the Treatment of Perianal Abscess and Fistula-in-Ano from the American Society of Colorectal Surgeons does not mention treatment with a biosynthetic plug for any indication.  

The American College of Gastroenterology does not mention treatment with a biosynthetic plug for any indication in any of their clinical guidelines.

The National Institute for Health and Clinical Excellence (NICE) published guidance on the suturable bioprosthetic plug in June 2007.  NICE determined that while there are no major safety concerns, evidence on the efficacy of the procedure is not adequate for it to be used without special arrangements for consent and for audit or research.  Further, clinicians wishing to perform the procedure should inform the clinical governance leads in their Trust, ensure that patients understand the uncertainty about the procedure’s efficacy and provide them with clear written information, and audit and review clinical outcomes, ideally through collaborative data collection.  Publication of safety and efficacy outcomes would be useful.


Evidence of efficacy of  fistula plug treatment is quite limited.  An RCT and retrospective comparisons did not demonstrate that fistula plugs improved healing rates or reduced recurrence of fistulas.  Case series report a wide range of results.  Randomized controlled trials with sufficient numbers of patients and with at least six months of follow-up reporting healing and recurrence rates and sphincter function before and after procedures are required.  

In light of the limited data available and inconsistent outcomes reported, use of fistula plugs is considered experimental, investigational, and unproven as the impact on net health outcome is not known.


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Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.

The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.

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The following codes may be applicable to this Medical policy and may not be all inclusive.

CPT Codes

43305, 43312, 44640, 46707, 57300, 57305, 57307, 57308



ICD-9 Diagnosis Codes

530.84, 565.1, 569.81, 619.1, 998.6

ICD-9 Procedure Codes

31.73, 46.74, 48.73, 48.93, 49.11, 49.12, 49.73, 70.73

ICD-10 Diagnosis Codes

K22.70 - K22.719, K60.3 - K60.5,  K50.013 - K63.2,  N82.2 - N82.4 , T81.83xa - T81.83xa

ICD-10 Procedure Codes


Medicare Coverage:

The information contained in this section is for informational purposes only.  HCSC makes no representation as to the accuracy of this information.  It is not to be used for claims adjudication for HCSC Plans.

The Centers for Medicare and Medicaid Services (CMS) does not have a national Medicare coverage position.  Coverage may be subject to local carrier discretion.

A national coverage position for Medicare may have been developed since this medical policy document was written.  See Medicare's National Coverage at <>.


Whiteford MH, Kilkenny J 3rd, Hyman N et al. Standards Practice Task Force; American Society of Colon and Rectal Surgeons. Practice parameters for the treatment of perianal abscess and fistula-in-ano (revised). Dis Colon Rectum 2005; 48(7):1337-42.

Surgisis® AFP™ Anal Fistula Plug – Product information.  West Lafayette, Indiana: Cook Biotech, Inc., (2006).

Johnson, E.K., Gaw, J.U., et al. Efficacy of anal fistula plug vs. fibrin glue in closure of anorectal fistulas.  Diseases of the Colon and Rectum (2006 March) 49(3):371-6.

Baillie, D.R., Stawicki, S.P. et al. Use of human and porcine dermal-derived bioprosthesis in complex abdominal wall reconstructions: a literature review and case report. Ostomy Wound Manage (2007 May) 43(5):30-7.

National Institutes for Health and Clinical Excellence (NICE). Closure of anal fistula using a suturable bioprosthetic plug. June 2007. Available at >. (accessed February 4, 2011). 

FDA – 510(k) Summary for SIS Fistula Plug.  Food and Drug Administration – Office of Device Evaluation, Center for Devices and Radiological Health.  Available at <>  (accessed February 4, 2011).

Ortiz H, Marzo J, Ciga MA et al. Randomized clinical trial of anal fistula plug versus endorectal advancement flap for the treatment of high cryptoglandular fistula in ano. Brit J Surg 2009; 96(6):608-12.

Christoforidis D, Pieh MC, Madoff RD et al. Treatment of transsphincteric anal fistulas by endorectal advancement flap or collagen fistula plug: a comparative study. Dis Colon Rectum 2009: 52(1)18-22.

Wang JY, Garcia-Aguilar J, Sternberg JA et al. Treatment of transsphincteric anal fistulas: are fistula plugs an acceptable alternative? Dis Colon Rectum (2009 Apr) 52(4):692-7

Chung W, Kazemi P, Ko D et al. Anal fistula plug and fibrin glue versus conventional treatment in repair of complex anal fistulas. Am J Surg 2009; 197(5):604-8.

Garg P, Song J, Bhatia A et al. The efficacy of anal fistula plug in fistula-in-ano: a systematic review. Colorectal Dis (2009 Jul);11(6):588-91

Clinical Available at >. (accessed February 4, 2011). 

Plugs for Fistula Repair.  Chicago, Illinois: Blue Cross Blue Shield Association Medical Policy Reference Manual. (December 2009). Surgery 7.01.123.

Policy History:

8/15/2011        Document updated with literature review.  Coverage language changed as follows: Biosynthetic fistula plugs, including plugs made of porcine small intestine submucosa or of synthetic material are considered experimental, investigational and unproven for all indications including, but not limited to, repair of anal and rectal fistulas. Complete revision of description and rationale. Codes updated.

5/1/2009          Revised/updated entire document

2/15/2007        New medical document

Archived Document(s):

Title:Effective Date:End Date:
Plugs for Fistula Repair07-15-201803-31-2019
Plugs for Fistula Repair04-15-201707-14-2018
Plugs for Fistula Repair04-15-201604-14-2017
Plugs for Fistula Repair04-15-201504-14-2016
Plugs for Fistula Repair01-01-201404-14-2015
Plugs for Fistula Repair08-15-201112-31-2013
Anorectal Fistula Repair Using an Acellular Xenogeneic Plug05-01-200908-14-2011
Anorectal Fistula Repair Using an Acellular Xenogeneic Plug02-15-200704-30-2009
Anorectal Fistula Repair using an Acellular Xenogeneic Plug01-01-200702-14-2007
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