OPEN Research Support

Karam Matlub Sørensen
Department of Surgery, Odense University Hospital

Projekt styring
Projekt status    Sampling ongoing
Data indsamlingsdatoer
Start 01.04.2017  
Slut 01.03.2020  

Surgical treatment of complex anal fistual. Retrospective cohort study

Short summary

A retrospective cohort study aiming to look at the outcome of surgical treatment of complex high anal fistula, by fistulectomy and anal sphincter repair, in 10 years period between 2006-2015. Surgical treatment of such complex fistula is demanding and associated with considerable risk of complications as well as recurrence. The primary end point is the recurrence rate of fistula following fistulectomy and sphincter repair. Secondary end points survey evaluation of fecal incontinence, quality of life and evaluation of eventual risk factors of recurrence.


Anal fistula presents the chronic form of anorectic sepsis. 25% of patients with anal sepsis end up with a complex fistula, including all high fistulae (involving more than one third of the anal sphincter), low fistula with secondary branches, fistulae associated with Crohn's disease and fistula in patients with incontinence. The surgical treatment of complex fistula is difficult and aims to completely heal the fistula, preventing recurrence, without affecting the anal sphincter function. The surgical treatment options include fistulectomy and sphincter repair, intersphincteric ligation of the fistula (LIFT), advanced flap and cutting Seton suture. All The methods have a relatively high recurrence and complication rate including the risk of anal incontinence.  Fistulectomy and primary reconstruction of the anal sphincter have been reported to have a success rate of between 90 - 95.8%, the rate of 7.1-9.7% and 5-30% of the incontinence rates in varying degree. There are few RCT in the literature about treatment complex anal fistula treatment and there is no conclusive evidence of which method is the best.  In addition, there is lack of knowledge about the functional outcome and quality of life in this group of patients.

Description of the cohort

Patient's recruitment will be done by searching the electronic patients journal system for adult patients with complex anal fistula treated at the surgical department, A, Odense University Hospital, between 2006-2016. An inclusion criterion is adult patient operated for complex anal fistula with fistulectomy and sphincter repair between 2006-2015. Exclusion criteria are simple anal fistula, rectovaginal fistula and recurrent fistula. Eligible patients will be asked to participate and those who will enroll, will be asked to fill survey analysis with SF-36 quality of life scheme and fecal incontinence Wexner score scheme. Surgical data and patient demography will be collected from the electronic patient journal.

Statistical analysis will be applied for the primary endpoint using Cox regression model.

Data and biological material

Data collection will be through:

  • SF-36 survey
  • Wexner Score survey
  • Clinical data
  • Surgical findings

Collaborating researchers and departments