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Completed

NCT Number: NCT07496216

Closed Versus Open Lateral Internal Sphincterotomy for Chronic Anal Fissure

This randomized controlled trial will compare closed versus open lateral internal sphincterotomy (LIS) under spinal anesthesia in patients with chronic anal fissure. The study will evaluate wound healing rates, postoperative pain, return to work, anal incontinence, and recurrence. A total of 160 patients will be randomized equally to either closed LIS or open LIS. The primary outcome will be complete wound healing at 6 weeks. Secondary outcomes include pain at 24 hours measured by Visual Analog Scale (VAS), return to work (days), anal incontinence at 6 weeks and 1 year, and recurrence at 1 year. Multivariate analysis will identify independent predictors of non-healing.

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Key information

Conditions

Chronic Anal Fissure

Age range

20 year–70 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Services Institute of Medical Sciences

Lahore, Punjab Province, 54000, Pakistan

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Diagnosis of chronic anal fissure (symptoms > 6 weeks)
  • Failure of conservative medical management (dietary fiber, stool softeners, topical lignocaine, and at least 4 weeks of topical glyceryl trinitrate 0.2%)
  • Willing to provide informed consent

Exclusion criteria

  • Multiple fissures
  • Concomitant anorectal pathology (anal fistula, abscess, significant hemorrhoids, rectal cancer)
  • Inflammatory bowel disease
  • Previous anorectal surgery
  • History of anoreceptive intercourse
  • Psychiatric disease or inability to consent

Treatment and study plan

Closed Lateral Internal Sphincterotomy

Procedure

A bivalve anal retractor will be inserted to visualize the intersphincteric groove. A number 11 scalpel blade will be introduced into the intersphincteric groove in the left lateral position, advanced to the level of the dentate line, and then rotated medially to divide the internal anal sphincter. A dry gauze wick soaked with xylocaine gel will be placed in the anal canal for hemostasis and removed on the evening of the operation day.

Open Lateral Internal Sphincterotomy

Procedure

A 1-2 cm curvilinear incision will be made in the intersphincteric groove in the left lateral position. The intersphincteric plane will be dissected to expose the internal anal sphincter, which will then be divided under direct vision up to the level of the dentate line. The wound will be left open to heal by secondary intention.

Primary outcomes

  1. Number of Patients with complete wound healing

    Time frame: 6 weeks

    Defined as evidence of scarring at the fissure site

  2. Anal incontinence

    Time frame: 6 weeks

    Wexner Continence Grading Scale

Secondary outcomes

  1. Pain score

    Time frame: 24 hours

    Pain score through visual analog score

  2. Return to work in days

    Time frame: 2 weeks

  3. Recurrence

    Time frame: 1 year

    Reappearance of ulcer or tear in previously healed scar

Sponsors and collaborators

Lead sponsor

Services Hospital, Lahore

Other Gov

Collaborators

  • Services Institute of Medical Sciences, Pakistan

Registry information

Official study title

Outcomes of Closed Versus Open Lateral Internal Sphincterotomy for Chronic Anal Fissure: A Randomized Controlled Trial

Acronym: LIS-CLOSED Tri

Important dates

Study start
2019
Primary completion
2025
Study completion
2026
First posted
Mar 27, 2026
Registry last updated
Mar 27, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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