Late presentation of small bowel obstruction secondary to displaced spiral tack fourteen years after ventral hernia mesh repair

A 65-year-old man presented acutely with abdominal pain to the emergency department. He had a background of gastric bypass surgery more than 15 years prior, with subsequent mesh repair of a midline incisional hernia 1 year later. He reported 12 hours of sudden onset generalised abdominal pain with no nausea or vomiting. His last bowel motion was prior to abdominal pain and he had not passed flatus since. On examination, his abdomen was soft with generalised tenderness but no peritonism. His vitals remained within normal range. His blood tests were all within the normal ranges.

His computed tomography (CT) scan, however, showed a segment of poorly enhancing small bowel with adjacent mesenteric congestion in the left upper quadrant, concerning for vascular compromise (Figure 1).

View Figure 1–2.

The patient proceeded for an exploratory laparotomy. Upon entry into the abdominal cavity, the bowel was inspected. A single metal spiral tack was located near the base of the small bowel mesentery, with two areas of the adjacent mesentery caught between the coils (Figure 2). This had resulted in an internal hernia involving a loop of distal jejunum. The appearance of the involved segment of bowel suggested chronic changes, indicating that the presenting episode was likely an acute on chronic obstruction.

The tack was easily dislodged with sharp dissection. Once the tack was removed, the internal hernia immediately resolved, and the congestion and discolouration improved. The entire small bowel was run and found to be viable, with no resection required. There was no abnormality identified in relation to the previous gastric bypass surgery.

He recovered well and discharged day four post-operatively.

Discussion

This case demonstrates a rare and interesting cause of small bowel obstruction secondary to a displaced intraperitoneal metal spiral mesh tack 14 years after its insertion. Interestingly, on retrospective review of this patient’s previous abdominal CT scans, the causative tack sits against the anterior abdominal wall in 2020 and is later seen in the central intra-abdominal position (the same position as the scan from admission displayed above) on a CT in 2024. This supports the conclusion that the tack migrated from its original position to cause the small bowel obstruction.

The use of mesh in abdominal hernia repair has greatly improved outcomes; however, a small but growing body of evidence demonstrates intra-abdominal tack–related complications. A PubMed review using “Spiral mesh” and “complications” was performed.^1–8 Multiple cases have been reported of small bowel obstruction secondary to spiral tacks caused by being loose in the intraperitoneal cavity or having a role in adhesion formation.^1–5 In some rare situations, loose tacks have also caused small bowel perforation.^6–8 These reported complications of metal tacks in hernia repair have in part motivated the shift towards the use of absorbable tacks. As mesh should be integrated into the surrounding tissue, in theory there is no need for permanent fixation. Current literature shows non-inferiority of absorbable compared with non-absorbable tacks in hernia repair.⁹

This case illustrates the potential complications of metal mesh tacks and the utility of diagnostic surgery in unclear imaging circumstances. The involved clinicians were initially concerned about the possibility of an internal hernia secondary to the patient’s previous gastric bypass, resulting in overlooking of the tacks demonstrated on the CT. While this did not impact the management and overall outcome of the patient, it highlights the potential for anchoring bias to affect how we approach diagnosis.