Hybrid Endoscopic-Laparoscopic Management of Colonoscopic Perforation within an Inguinal Hernia Sac

Summary

This case report demonstrates a multidisciplinary management pathway for a rare iatrogenic colonic perforation entrapped within an inguinal hernia sac, using a hybrid strategy of immediate endoscopic closure followed by definitive laparoscopic resection.

Abstract

Colonoscopy is the gold standard for colorectal cancer screening, yet it carries the risk of iatrogenic perforation. A rare, hazardous subtype involves colonoscope incarceration and perforation within an inguinal hernia sac, mechanically driven by a "hinge effect" during withdrawal. The confined anatomical space often masks typical peritoneal signs, challenging diagnosis. A case is presented of a 71-year-old male (Body Mass Index: 24.2 kg/m²) undergoing a routine screening colonoscopy. Significant resistance occurred at the sigmoid colon during withdrawal, revealing a 1.0 cm full-thickness defect. First, an immediate endoscopic "damage control" strategy was employed using a through-the-scope purse-string suture technique combining a nylon endoloop with titanium clips to seal the defect acutely within 15 min. Crucially, an emergency contrast-enhanced Computed Tomography (CT) scan performed at Hour 1:00 post-event identified the perforated segment entrapped within a 4 cm left inguinal hernia sac, suggesting surgical exploration over exclusive conservative observation due to visceral ischemia risks. Consequently, the patient underwent laparoscopic partial sigmoidectomy of a 10 cm segment and high ligation of the hernia sac with internal ring closure under a stable 12 mmHg pneumoperitoneum (operative duration: 165 min; blood loss: 15 mL). The patient recovered uneventfully and was discharged on the seventh postoperative day. Quantified follow-up at 1 and 3 months confirmed complete functional recovery and zero recurrence. This case highlights the need for pre-procedural hernia assessment and suggests that a hybrid approach, pairing immediate endoscopic containment with planned surgical repair, may present a feasible alternative pathway for managing this rare emergency.

Introduction

Colonoscopy is widely regarded as the gold standard for colorectal cancer (CRC) screening, diagnosis, and therapeutic intervention. With the global scale-up of CRC screening initiatives, the number of colonoscopic procedures has risen dramatically. Although colonoscopy is generally safe, it remains an invasive procedure inherently associated with procedural risks. Perforation, identified by the American College of Gastroenterology (ACG) quality indicators as one of the most severe adverse events, occurs in 0.01%–0.1% of diagnostic colonoscopies and up to 0.3% of therapeutic procedures^1,2. Most iatrogenic perforations involve the sigmoid colon or rectosigmoid junction and result from direct mechanical injury, such as loop formation, excessive torque, or barotrauma. However, when perforation occurs within a discrete anatomical compartment, specifically inside an inguinal hernia sac (intra-hernial perforation), clinical presentation, diagnostic evaluation, and therapeutic decision-making become markedly more complex.

Inguinal hernias are highly prevalent among older men. Prior reports have documented a distinct complication in such patients undergoing colonoscopy: entrapment or incarceration of the colonoscope within the hernia sac^3,4,5. This phenomenon arises directly from anatomical distortion. In left-sided inguinal hernias, the sliding sigmoid colon frequently resides within the sac. During scope advancement, the hernia neck functions as a fixed, rigid fulcrum, termed a “pulley” by Koltun et al.⁶. As the colonoscope traverses this segment, axial force is redirected laterally at the fulcrum, generating a shearing stress perpendicular to the bowel wall. This biomechanical alteration, commonly referred to as the “hinge effect”, can lower the threshold for full-thickness mechanical tear, rendering the tissue vulnerable to perforation even under minimal applied force⁷.

Confirmed cases of perforation confined entirely within a hernia sac remain exceedingly rare in the medical literature⁷. Such intra-hernial perforations pose a substantial diagnostic challenge due to their occult clinical presentation. Unlike intraperitoneal perforations, which typically trigger acute generalized peritonitis, characterized by board-like rigidity and rebound tenderness, following rapid spillage of luminal contents, perforations contained within the hernia sac lack classic peritoneal signs, frequently leading to delayed recognition.

Pathophysiologically, colonic loops long-entrapped or sliding within an inguinal hernia configuration are uniquely predisposed to localized microcirculatory compromise^8,9. The mechanical constriction at the narrow hernia neck often impairs venous return and lymphatic drainage, precipitating progressive mural edema and interstitial congestion^8,9. When a mechanical perforation occurs in this pre-existing low-compliance milieu, the compressed space within the sac traps contaminated luminal contents under pressure⁷. This specific microenvironment can substantially accelerate localized tissue necrosis, facilitate progressive necrotizing soft-tissue infection along the inguinal fascial planes, and potentially lead to rapid septic deterioration if the structural risk is not addressed proactively^7,8,9.

Given these pathophysiological complexities, timely recognition and precise anatomical localization of the perforation site relative to the hernia sac are critical determinants of patient outcomes. Multi-detector computed tomography (MDCT) plays an indispensable role in this emergency setting. Beyond detecting extraluminal free air, MDCT enables definitive spatial mapping of the injury. The presence of air bubbles or fluid collections strictly localized within the inguinal hernia sac on CT provides supportive diagnostic evidence that reliably distinguishes intra-hernial from free intraperitoneal perforation¹⁰. Based on published clinical series, this localized radiological presentation often alerts clinicians to the potential failure of exclusive conservative observation and suggests the feasibility of early surgical exploration over wait-and-watch strategies due to the underlying anatomical compartment risk^10,11.

Therapeutically, management of iatrogenic colonic perforation has evolved from open laparotomy toward minimally invasive strategies. For small, clean, and immediately recognized perforations, endoscopic closure using through-the-scope (TTS) clips or over-the-scope clips (OTSC) is well-established as a safe alternative to surgery, avoiding the morbidity of open abdominal surgery^12,13,14.

However, in the specific context of an intra-hernial perforation, isolated endoscopic closure presents inherent clinical limitations. While endoscopic clipping can achieve immediate mucosal apposition and airtight sealing, it neither alleviates the external mechanical constriction at the hernia neck nor corrects the underlying anatomical defect¹⁵. According to expert consensus guidelines, endoscopic-only management may be high risk when there is a risk of ongoing microvascular ischemia secondary to persistent visceral entrapment, as the compromised tissue perfusion severely impairs spontaneous primary healing and predisposes the site to delayed dehiscence^15,16,17. Consequently, a hybrid strategy, combining immediate endoscopic purse-string closure as an immediate damage-control measure to prevent free peritoneal soilage, followed by planned laparoscopic exploration, presents a practical and risk-stratified alternative pathway to address both the visceral injury and the anatomical defect concurrently^15,18.

To provide readers with clear practical applicability guidance, the selection of this hybrid approach over isolated endoscopic clipping is preferred based on three objective criteria: (1) radiological confirmation of the perforation site being completely compartmentalized within a non-reducible hernia sac; (2) clinical signs of localized ischemia, structural entrapment, or persistent regional pain despite successful clipping; and (3) the presence of a large or symptomatic abdominal wall defect that requires mandatory surgical repair to ensure long-term bowel viability and eliminate the risk of recurrent strangulation. By detailing the step-by-step decision-making process, from the intra-procedural recognition of “withdrawal resistance” to radiological confirmation and definitive surgical correction, this article aims to provide endoscopists and surgeons with a practical guide for managing this rare but potentially catastrophic complication.

Case presentation:

A 71-year-old male with a Body Mass Index (BMI) of 24.2 kg/m² and an American Society of Anesthesiologists (ASA) status of Class II was admitted for a routine screening colonoscopy. The patient had a long-standing history of a reducible left inguinal hernia, which had not been surgically repaired before the procedure. The colonoscopy was performed under intravenous sedation using a standard colonoscope with room air insufflation. The insertion of the scope was successful up to the cecum with no mucosal abnormalities noted. However, during the withdrawal phase, a transient increase in resistance was experienced by the operator. Upon further inspection at approximately 30 cm from the anal verge (sigmoid colon region), a full-thickness defect of approximately 1.0 cm was identified, with visible serosa and minor bleeding, confirming an iatrogenic perforation (Figure 1A). While hemodynamic stability was maintained, immediate endoscopic intervention was initiated as an acute damage-control measure.

Following the endoscopic repair, which was accomplished within 15 min, an emergency contrast-enhanced abdominal and pelvic CT scan was performed at Hour 1:00 post-event. The imaging revealed that the perforated segment of the colon was located within a 4 cm left inguinal hernia sac, which contained a small amount of free air and inflammatory exudate (Figure 2). A Multidisciplinary Team (MDT) consensus, including gastrointestinal surgeons and endoscopists, was finalized at Hour 2:30, determining that the risk of delayed ischemia and repair failure within the restricted space of the hernia sac necessitated definitive surgical intervention over exclusive conservative observation.

Diagnosis, assessment, and plan

Diagnosis: Iatrogenic colonic perforation located within an incarcerated left inguinal hernia sac.

Assessment: The clinical priority was to achieve immediate closure of the perforation to prevent extensive peritoneal contamination. Although endoscopic closure was initially successful in achieving an airtight seal, the CT finding of a perforation within a hernia sac significantly increased the long-term risk of localized soft-tissue infection and microcirculatory ischemia. The restricted anatomical space and unique blood supply of the hernia sac render spontaneous healing highly unlikely compared to free intra-abdominal perforations.

Plan: Following the urgent MDT discussion and the acquisition of explicit written informed consent from the patient, emergency laparoscopic surgery was scheduled for Hour 2:55. The dual-objective surgical plan included: (1) Laparoscopic exploration and partial sigmoidectomy of a 10 cm segment to ensure healthy, well-perfused tissue margins with a primary end-to-end stapled anastomosis, and (2) High ligation of the inguinal hernia sac without mesh placement to address the underlying anatomical cause and prevent recurrence while avoiding foreign material in a contaminated environment.

Protocol

This clinical protocol was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee of The First Hospital of PuTian City (Approval No. 2024-168). Written informed consent was obtained from the study participants. The reagents and the equipment used are listed in the Table of Materials.

1. Pre-procedural risk assessment and preparation

1. Elderly male patients were systematically screened for a history of abdominal wall or inguinal hernias via physical palpation and medical chart review before initiating the colonoscopy.
2. Specific iatrogenic risks, including “visceral incarceration within the hernia sac” and “intra-hernial perforation,” were documented and communicated on the specialized informed consent form for patients with known hernias.
3. Elective surgical hernia repair was recommended before scheduling an elective colonoscopy for patients identified with large (>4 cm orifice) or symptomatic hernias to prevent entrapment complications.

2. Intra-procedural management of luminal resistance

1. All scope movements were stopped immediately if increased resistance was felt during the scope withdrawal phase. No forced blind backward traction was applied.
2. Potential scope entrapment was identified by performing immediate physical palpation of the groin to check for a tense swelling or utilizing brief fluoroscopic X-ray imaging to verify if the colonoscope was looped or trapped within a hernia sac.
3. Safe reduction techniques were employed once the scope was confirmed to be trapped. The patient's position was changed (e.g., to right lateral or supine), steady manual pressure was applied directly over the hernia orifice, and high-volume lumen suction was activated to collapse the colonic wall before attempting further careful scope withdrawal.
   1. Successful colonoscope reduction and release were objectively confirmed by the immediate restoration of smooth, unconstrained shaft mobility, the complete visual disappearance of luminal twisting under direct endoscopic vision, and the total resolution of the tense external groin swelling upon physical palpation.

3. Endoscopic perforation closure via through-the-scope purse-string suture

1. Luminal air pressure was managed immediately upon identifying a full-thickness defect. The endoscopic insufflator was switched from room air to carbon dioxide (CO₂) mode, and the flow rate was restricted to less than 1.4 L/min to minimize the risk of tension pneumoperitoneum.
2. A nylon endoloop loop delivery device was deployed through the single-channel of the endoscope, opening the loop circumference completely to encircle the margins of the perforation site.
3. The endoloop was anchored to healthy mucosal tissue. Multiple through-the-scope (TTS) titanium endoclips were deployed sequentially along the perimeter of the defect, capturing both the nylon string and 2–3 mm of the surrounding healthy mucosal margins.
4. A complete, airtight closure was secured. The endoloop was tightened using its plastic slider mechanism to constrict the tissue defect, and additional titanium clips were applied at the center of the cinched site if necessary.
   1. The success of the closure was verified by confirming three distinct visual checkpoints: the complete absence of a visible mucosal defect, tight symmetrical positioning of all anchoring clips, and a puckered/wrinkled mucosal appearance with zero active hemorrhage.

4. Multidisciplinary emergency response and surgical intervention

1. Emergency diagnostic imaging was initiated. An immediate contrast-enhanced multi-detector abdominal and pelvic computed tomography (MDCT) scan was performed within 1 h post-event to determine the spatial localization of extraluminal gas or fluid and to evaluate the regional vascular blood supply.
   1. The MDCT scan was executed utilizing a standardized high-resolution protocol consisting of a 1.0 mm slice thickness, a tube voltage of 120 kV, an automatic tube current modulation range of 150–250 mAs, and the intravenous bolus administration of 100 mL of non-ionic iodinated contrast medium at an injection rate of 3.5 mL/s.
2. A rigid operational threshold was established for surgical transition. An immediate escalation to emergency surgery was proceeded with once CT imaging confirmed that the perforation was compartmentalized within the hernia sac, or if objective criteria for tissue ischemia and compromised bowel viability were identified, rendering isolated endoscopic closure insufficient.
   NOTE: The criteria triggering mandatory surgical intervention included a localized bowel wall thickening exceeding 5 mm, presence of pneumatosis intestinalis, or an absolute absence of mural enhancement during the arterial phase on contrast CT; supplemented intraoperatively by the visual confirmation of a dusky, un-reactive purple discoloration of the serosa, a lack of active marginal bleeding upon localized incision, and a total absence of visible colonic peristalsis.
3. Laparoscopic surgical exploration was executed. Pneumoperitoneum was established using standard techniques, and a stable insufflation pressure of 12 mmHg was maintained. The herniated space was systematically inspected to evaluate the grade of abdominal contamination (e.g., Hinchey Classification) and the structural integrity of the endoscopic clips.
4. Definitive visceral resection was performed. A 10 cm segment of the damaged colon (partial sigmoidectomy) was resected to guarantee completely healthy, well-perfused tissue margins. The gastrointestinal tract was reconstructed by executing a primary end-to-end stapled anastomosis using a laparoscopic linear or circular cutting stapler.
5. The hernia defect was managed concurrently. A high ligation of the hernia sac was completed during the same laparoscopic session. The placement of synthetic mesh materials was deliberately avoided because localized contamination (Hinchey Stage I) was present, thereby reducing the long-term risk of foreign-body infection.

5. Postoperative management and quantified follow-up

1. A standardized infection and nutritional control regimen was administered. A mandatory postoperative intravenous antibiotic pathway was maintained, established as a strict clinical requirement due to the intra-hernial contamination risk rather than an optional illustrative example, consisting of Ceftriaxone (2.0 g every 24 h) combined with Metronidazole (0.5 g every 8 h) for 3 consecutive days. Total parenteral nutrition or strict fluid intake was provided, tailored to the recovery of bowel sounds and flatus.
2. The patient's recovery kinetics were monitored daily. Systemic inflammatory parameters, including white blood cell (WBC) counts and C-reactive protein (CRP) trends, were monitored, and physical signs were evaluated for anastomotic leakage, delayed hemorrhage, or surgical wound-site infection.
3. Structured, quantified long-term follow-up assessments were conducted. Mandatory clinical evaluations were scheduled at 1 and 3 months post-discharge. Recovery success was quantified by verifying four objective parameters: the restoration of normal bowel function/habits, complete primary healing of the surgical incisions, the absence of anastomotic strictures on clinical examination, and a 0% hernia recurrence rate on physical examination.

Results

The patient was an elderly male with a Body Mass Index (BMI) of 24.2 kg/m² and an American Society of Anesthesiologists (ASA) physical status of Class II. He underwent a routine screening colonoscopy utilizing standard room air insufflation. The colonoscopy proceeded smoothly to the cecum without mucosal abnormalities. However, during the withdrawal phase, specifically at approximately 30 cm from the anal verge (sigmoid colon region), the operator detected a transient increase in resistance. Upon detailed insp...

Discussion

This case illustrates a rare yet mechanistically distinct form of iatrogenic injury: sigmoid colon incarceration followed by perforation within an inguinal hernia sac during colonoscopy¹. Although colonoscopy remains the gold standard for colorectal cancer (CRC) screening, diagnosis, and intervention, perforation constitutes its most severe procedural complication. According to consensus quality indicators from the American College of Gastroenterology (ACG) and the American Society for Gastrointes...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Absorbable Suture (1#)	Ethicon (Johnson & Johnson)	VCP359H	Coated synthetic polyglactin absorbable suture (USP 1) utilized for fascial closure. Referred to as "absorbable suture" in text.
Carbon Dioxide (CO2) Insufflator	Olympus	UCR	Standard CO2 regulation unit for medical endoscopic procedures. Referred to as "CO2 insufflator" in text.
CT Scanner	Neusoft Medical Systems	NeuViz 128	Multi-detector computed tomography (MDCT) system for diagnostic imaging. Referred to as "MDCT scan" in text.
Endoloop (Nylon Loop)	Olympus	MAJ-254	Pre-tied nylon loop ligating device with a 30 mm diameter loop. Referred to as "endoloop loop delivery device" in text.
Endoscopic Titanium Clips	Olympus	HX-610-090	Rotatable through-the-scope titanium hemostatic clips. Referred to as "titanium clips" or "endoclips" in text.
Laparoscopic Imaging System	Olympus	Visera 4K	High-definition 4K laparoscopic camera control unit and tower. Referred to as "laparoscopic system" in text.
Laparoscopic Trocars	Ethicon (Johnson & Johnson)	B5LT / B12LT	Bladed and bladeless surgical trocars (5 mm and 12 mm diameters). Referred to as "laparoscopic trocars" in text.
Linear Cutter Stapler	Ethicon (Johnson & Johnson)	TLC55 / TLC75	Heavy-duty linear surgical cutter and stapler for gastrointestinal tract reconstruction. Referred to as "linear cutting stapler" in text.
Negative Pressure Drainage Tube	Pacific Hospital Supply	Simplastic	Medical silicone round negative-pressure drainage system. Referred to as "pelvic silicone drain" in text.
Silk Suture (1-0)	Ethicon (Johnson & Johnson)	EH7350H	Non-absorbable braided silk surgical suture (USP 0). Referred to as "silk suture" in text.
Ultrasonic Scalpel	Ethicon (Johnson & Johnson)	HARH36	High-frequency ultrasonic surgical shears for soft-tissue dissection and coagulation. Referred to as "ultrasonic scalpel" in text.
Veress Needle	Ethicon (Johnson & Johnson)	UV120	Sterile single-use pneumoperitoneum needle (120 mm length). Referred to as "pneumoperitoneum needle" in text.
Video Colonoscopy System	Olympus	CF-H290I	High-definition single-channel electronic video colonoscope. Referred to as "standard colonoscope" in text.