A 62-year-old man presented with progressively increasing swelling and pain in left thigh. He had a complicated past surgical history which included a subtotal colectomy and ileosigmoid anastomosis for an obstructing cancer and an endarterectomy of the common femoral artery. His CT scan revealed soft tissue emphysema of the thigh. A laparotomy performed showed a communication between the previously stapled terminal ileal stump and the thigh with intestinal gas escaping into the lower limb. This patient was discharged well after a proximal loop ileostomy and repair of the terminal ileum.
Soft tissue emphysema of lower limb of gastrointestinal origin is a rare occurrence. Various causes have been documented in the past.1,2 We report a case of a man developing a communication between the stapled terminal ileal stump and the thigh leading to soft tissue emphysema of the lower limb. We were unable to find such a case in literature.
A 62-year-old man was referred to the accident and emergency department of the hospital with a four-day history of progressively increasing swelling and pain in the left thigh two months after undergoing bowel surgery. On examination, the patient was afebrile and haemodynamically stable. His abdomen showed mild fullness in the left flank but was soft. There was a flexion deformity at the left hip and knee with a diffuse painful swelling of the left thigh. There were no local signs of inflammation. The swelling was tense and it had a tympanic note on percussion. His laboratory investigations were normal except for a raised white cell count. Suspecting a collection, a CT scan of his abdomen and pelvis was requested. This revealed a large amount of gas surrounding the left hip and thigh extending superiorly into the left gluteal region, the abdominal wall in the left iliac fossa and the left iliopsoas muscle. (Fig. 1)
Figure 1:: CT scan section through thigh showing gas surrounding the left thigh.
There was a lack of thickening of fascia or soft tissue inflammation surrounding the pockets of gas. There was no free fluid in the abdomen or pelvis and the upper abdominal solid organs appeared normal.
The patient's past surgical history was complicated in that he had undergone a subtotal colectomy with a stapled end to side ileo-sigmoid anastomosis 15-months before admission for large bowel obstruction secondary to a left colonic cancer. Histopathology had revealed a pT3 N1 poorly differentiated adenocarcinoma. In the following months he developed worsening peripheral vascular disease with rest pain in his left lower limb. For this he underwent an endarterectomy and angioplasty of the left common femoral artery with a Dacron graft nine months after his first surgery. The inguinal ligament was partially divided during this procedure. Three months later he presented with a left psoas abscess and a tender mass in his left iliac fossa. A water-soluble contrast enema showed contrast leaking into the abscess cavity. A computerised tomography (CT) guided percutaneous drainage was performed which revealed faecal contents and a laparotomy was performed. At laparotomy a defect was noted where the inguinal ligament had been divided at the previous surgery. Adherent to this was a loop of small bowel and the terminal ileal stump of the end to side ileo-sigmoid anastomosis. Both had perforated at the site forming an abscess cavity. Drainage of the abscess and biopsies from the wall of the abscess cavity with restapling of the terminal ileum and resection of the adherent loop of small bowel was carried out. Histopathology revealed inflammatory changes with no evidence of tumour recurrence in any of the specimens. The patient had a prolonged recovery and was discharged after a hospital stay of 6 weeks.
During this admission the patient underwent a further laparotomy where a communication was found between the staple line of the terminal ileal stump and the thigh. The communication was approximately the size of a pin head at the site of the previous defect through an opening in the inguinal ligament. There was no pus and the gas filled thigh was decompressed through the abdominal cavity. The terminal ileal stump was restapled and a proximal loop ileostomy was fashioned. Following this surgery the patient had an uneventful recovery and remained well at clinic review.
Figure 2 : Likely mechanism of spread of gas.
Subcutaneous emphysema of the anterior abdominal wall has been described as an uncommon complication of gastrointestinal disease. Lower limb involvement in such a process has been documented but is rare. (1,2) The causes for extrapelvic spread of gastrointestinal disease to lower limb that have been reported include colonic carcinoma, diverticulitis, appendicitis, traumatic perforation of the rectum, perforation of terminal ileum due to ingestion of foreign body, Crohn’s disease and periureteral abscess perforating the caecum. (1,2) We were unable to find a previous case similar to the present one.
The pathways of spread of infection from the abdomen to the lower limb that have been described include the pelvic muscles iliopsoas, obturator internus and pyriformis with their extra-pelvic insertions and fascial investments. (1,2) Pelvic collections may also spread via the branches of the internal iliac vessels that penetrate the pelvic fascia to reach the gluteal region (the superior and inferior gluteal vessels). We believe the mechanism of spread of the gas was through the opening in the inguinal ligament created due to its division during the endarterectomy and angioplasty of the left common femoral artery.
It is likely that the outlet in the terminal ileal stump allowed venting of gas while the faecal contents passed down the intact ileo-sigmoid anastomosis in the present case. (Fig. 2) Most authors agree that the gas is of gut luminal origin. (2-4) The following reasons support this belief - the pressure gradient between the intestinal lumen and the surrounding soft tissues is more than 60mm H 2O during peristalisis and as was seen in the present case, the accumulation of gas is often very rapid and finally, the surrounding soft tissues of the thigh often show little evidence of infection. (3)
Radiology is helpful in the differential diagnosis of lower limb emphysema with CT being very sensitive for detecting even small amounts of gas. (3) Large pockets of gas as were as were observed in this case are often seen in emphysema as a result of an enteric fistula due to the high-pressure gradient between the gut lumen and the soft tissues. (3) In contrast in emphysematous cellulitis, a large number of small bubbles of gas form a honeycomb pattern in the fibrous meshwork of the subcutaneous tissues while in myositis intramuscular gas outlines individual muscle bundles. (5)
This case of ileal stump breakdown leading to soft tissue emphysema of the lower limb was almost certainly related to partial division of the inguinal ligament at endarterectomy and angioplasty of the common femoral artery. This first lead to a defect at the site and subsequently to a communication between the stapled terminal ileal stump from an end to side ileosigmoid anastomosis and the thigh. This communication allowed only intestinal gas through the defect while the patient continued to pass a normal bowel motion through his patent ileosigmoid anastomosis.
1. Robbins PL, Sutherland DER, Najarian JS, Bernstein WC: Emphysema of the leg as a presenting sign of large-intestinal perforation. Dis Colon Rectum 20:144-148,1977
2. Meyers MA, Goodman KJ: Pathways of extrapelvic spread of disease: Anatomic-radiologic correlation. AJR 125:900-909,1975
3. Jager GJ, Rijssen HV, Lamers JJH: Subcutaneous emphysema of lower extremity of abdominal origin. Gastrointest Radiol 15:253-258,1990
4. Bohrer SP, Bodine J: Perforated cecal carcinoma presenting as thigh emphysema. Ann Emerg Med 12:42-44,1983
5. Weens HS, Clements JL: Nonparasitic inflammatory diseases of the soft tissues. Semin Roentgenol 7:37-45,1973
