Internal Hernia After Laparoscopic One-Anastomosis (Mini) Gastric
Bypass: Video Case Series of a Single-Center Experience
Received: 21 December 2020 /Revised: 4 March 2021 /Accepted: 16 March 2021
Internal hernia (IH) after one-anastomosis gastric bypass (OAGB) was thought to have an extremely low incidence. In this video,
we report three cases of post-OAGB symptomatic internal herniation. The first case is a 45-year-old female who presented 4
months after her OAGB with crampy abdominal pain and reflux symptoms. An exploratory laparoscopy showed Petersen’s
hernia; the hernia was reduced with no ischemia and the defect was closed. The second case is a 40-year-old male who presented
7 months after his surgery with abdominal pain and reflux. An exploratory laparoscopy showed Petersen’s hernia; bowel was
reduced and defect was closed through a laparotomy. The third case is a 64-year-old male who presented with refractory biliary
reflux after OAGB. An elective diagnostic laparoscopy showed Petersen’s hernia; the hernia was reduced and defect was closed.
All patients recovered well with no recurrence of symptoms on follow-up. Internal hernia after OAGB is more common than the
reported incidence. The threshold for diagnostic laparoscopy should be lowered for a OAGB patient with symptoms suggestive
Keywords Bariatric surgery complications .One-anastomosis gastric bypass .Mini-gastric bypass .Internal hernia .Petersen’s
hernia .Case report .Case series
One-anastomosis gastric bypass (OAGB) has been recognized
as one of the standard bariatric procedures due to its efficacy
and safety [1,2]. It was believed that the incidence of internal
hernia (IH) after OAGB is extremely rare compared to the
Roux-en-Y gastric bypass (RYGB) [3–5], with only 5 cases
reported in literature [6–10]; however, this may have been
under-reported . We present a video case series from a
single center with the operative management.
Seventy-one OAGB cases have been performed in our center.
Three patients developed IH after OAGB. The first is a 45-
year-old female who had undergone a laparoscopic conver-
sion of sleeve gastrectomy (SG) to OAGB for weight regain.
She presented to the Emergency Department (ED) 4 months
later with left-sided abdominal pain and reflux symptoms. An
abdominal CT scan showed clustering of bowel loops in the
left upper quadrant with a suspicion of internal hernia through
Petersen’s defect without ischemia. An endoscopy showed
evidence of bile gastritis. The patient was taken for a diagnos-
tic laparoscopy. Intraoperatively, the efferent limb was found
dilated and herniated through Petersen’s defect with twisting
of the anastomosis. The bowel was reduced successfully. The
defect was closed with continuous non-absorbable sutures.
The patient recovered well. She was followed up to 2 years
post-op with no reoccurrence of pain or reflux.
Department of Bariatric and Metabolic Surgery, University College
London Hospitals, London, UK
Department of Bariatric Surgery, Specialized Surgery Center, King
Abdullah Medical City, Mecca, Saudi Arabia
/ Published online: 31 March 2021
Obesity Surgery (2021) 31:2839–2840