A clinical conundrum with a radiological answer

Abstract

An 82-year-old woman with longstanding medial thigh pain presented with a 5-day history of constipation, vomiting, abdominal pain and distension. She was unable to pass flatus for the preceding 24 hours and had a past history of laparoscopic abdominal surgery. Computed tomography of the abdomen and pelvis revealed a right-sided obturator hernia containing a dilated loop of small bowel. She underwent emergency surgery for a right obturator hernia repair by limited laparotomy and was discharged after an extended stay complicated by postoperative atrial fibrillation. KEYWORDSObturator hernia -Abdominal hernia -Bowel obstruction -Computed tomography Case HistoryAn 82-year-old woman was admitted to the acute surgical ward with a 5-day history of constipation, feculent vomiting, abdominal pain and distension. She had presented to the accident and emergency department the day before with similar complaints. However, it was thought that her constipation was secondary to codeine use for neuropathic right lower limb pain and she was discharged with laxatives. She had a background history of osteoarthritis, cholangitis, a laparoscopic cholecystectomy with postoperative atrial fibrillation and a three-month history of right medial thigh pain, thought to be sciatica.The patient had not passed a bowel motion in 5 days prior to her presentation and had not passed flatus in 24 hours. On admission, her abdominal pain was generalised and constant, having in the preceding days been intermittent and colicky in nature. This pain was associated with dark brown, feculent vomiting. Clinical examination revealed a stable, thin patient of 40kg with a temperature of 36.5°C, a heart rate of 85 beats per minute, blood pressure of 130/62mmHg, a respiratory rate of 18 breaths per minute and oxygen saturation of 94% on room air. Her abdomen was visibly distended with generalised tenderness but no guarding or rigidity was elicited. She had no palpable hernias and digital rectal examination revealed an empty rectum.A full blood count showed a normal white cell count with a neutrophilia of 9.1 Â 10 9 /l. The patient's C-reactive protein level was also raised at 16mg/l. Her renal profile was normal. However, her arterial blood gas showed a metabolic alkalosis with respiratory compensation and a normal lactate, in keeping with her history of protracted vomiting. Plain film of the abdomen demonstrated dilated loops of small bowel consistent with her working diagnosis of a small bowel obstruction. The patient was made nil by mouth. A catheter was passed and a nasogastric tube left on free drainage with four-hourly aspirates. She was maintained on intravenous fluids overnight awaiting computed tomography (CT) of the abdomen and pelvis the following morning. The CT revealed multiple fluid and gas filled dilated loops of small bowel throughout the abdomen and pelvis, and a right obturator hernia containing a loop of dilated small bowel measuring a maximum of 2.2cm in diameter with a tapered neck (Figs 1-3). There was no evidence of perforation....

Unusual cause of mechanical small bowel obstruction in a cachectic older multiparous woman

“…An obturator hernia is a relatively rare finding, accounting for 0.2%–1.6% of cases of mechanical intestinal obstruction 1 2. Recent studies have shown a higher incidence of 6% and suggested that the true incidence maybe higher if more patients underwent radiological evaluation prior to definitive management 3. Obturator hernias have a female predisposition with one study quoting an 1:16 male to female ratio 4.…”