Strangulated Small Bowel Within a Posterior Rectus Sheath Hernia in a Patient Without Prior Abdominal Surgery.

BACKGROUND: Posterior rectus sheath hernia is an exceptionally rare interparietal abdominal wall hernia in which abdominal contents herniate through the posterior rectus sheath into the retrorectus space while the anterior rectus sheath remains intact. Clinical diagnosis may be difficult because the hernia remains confined within the abdominal wall, and delayed recognition may result in bowel strangulation. We report a rare case of spontaneous posterior rectus sheath hernia complicated by bowel necrosis requiring staged operative management. CASE PRESENTATION: A 73-year-old woman with no history of previous abdominal surgery presented with a 48-h history of progressively worsening epigastric abdominal pain, nausea, and emesis. Computed tomography demonstrated a narrow-neck posterior rectus sheath hernia containing incarcerated small bowel with decreased bowel wall enhancement, proximal small bowel dilatation, and findings concerning for strangulation. Emergency exploratory laparotomy confirmed an approximately 1-cm posterior rectus sheath defect with incarcerated mid-jejunum within the retrorectus space. Following reduction, a 10-cm segment of necrotic jejunum with pinpoint perforation required resection. Because adjacent bowel viability remained uncertain, temporary abdominal closure with negative-pressure therapy was performed followed by a planned second-look laparotomy 24 h later. Re-exploration demonstrated complete recovery of the remaining bowel, allowing stapled side-to-side functional end-to-end small bowel anastomosis and primary repair of the posterior rectus sheath without mesh because of contamination. The patient experienced an uncomplicated postoperative recovery, was discharged home on postoperative day five, and remained free of recurrent posterior rectus sheath hernia or incisional hernia at 1-month clinical follow-up and 1-year computed tomography surveillance. CONCLUSION: Posterior rectus sheath hernia should be considered in patients presenting with small bowel obstruction and an interparietal abdominal wall defect on computed tomography, even in the absence of previous abdominal surgery. Careful recognition of the characteristic retrorectus anatomy and prompt operative intervention are essential when strangulation is suspected. This case demonstrates successful staged management with bowel resection, planned second-look laparotomy, and durable primary repair with no recurrence at 1 year.