Small bowel obstruction in percutaneous fixation of traumatic pelvic fractures.

The use of external fixation for the initial treatment of unstable, complex pelvic injuries with hemodynamic instability remains an effective treatment for multiply injured patients. Bowel entrapment within a pelvic fracture is a rarely reported, potentially fatal complication. Here, we report a polytrauma patient with pelvic fractures who developed an intestinal obstruction after an external fixation. At an explorative laparotomy, we found an ileum segment trapped in the sacral fracture. Reported cases of bowel entrapment in pelvic fractures, especially in sacral fractures, are exceedingly rare. The diagnosis is often delayed due to difficulty distinguishing entrapment from the more common adynamic ileus. In conclusion, clinicians and radiologists should be aware of this potentially lethal complication of pelvic fractures treatment. To exclude bowel entrapment, patients with persistent ileus or sepsis should undergo early investigations.

INTRODUCTION

Polytrauma patients with pelvic fractures challenge the surgeon's diagnostic, operative, and peri-operative management skills, especially because of the frequent associated injuries to the abdominal viscera. The use of an external fixator for the initial and, in some cases, the definitive fixation of unstable, complex pelvic injuries with hemodynamic instability is effective for multiply injured patients.[1]

Bowel entrapment within a pelvic fracture is rare, but can be fatal. This important diagnosis is difficult to make, even with current imaging methods.

We present a documented case of small bowel entrapment in a sacral fracture stabilized with an external fixator.

CASE REPORT

A 51-year-old man, with no medical history of note, was in a motorcycle accident. In the emergency room, he presented with hemodynamic instability due to a pelvic fracture and a concomitant catastrophic soft tissue injury involving the scrotum, perineum, and anus with absence of the anal reflex. The extended EcoFast showed no fluid collection in the abdomen and no pneumothorax. The pelvis X-ray showed ischiopubic and ileopubic fractures associated with symphyseal disruption (anterior posterior fracture APII, see Young and Burgess). After the resuscitation phase, the patient underwent full-body computed tomography (CT) [Figure 1] and was subsequently transferred to the operating theater. His pelvis was fixed with external screws [Figure 2].

Figure 1

Cross-sectional CT image of the abdomen. The white vertical arrow indicates the sacral fracture

Figure 2

Pelvis X-ray showing the external screws

An exploratory laparotomy was performed to exclude abdominal organ damage, and a loop colostomy was performed for the anal incompetence. Then, the patient was admitted to our intensive care unit (ICU), where no bowel function was observed for the first 6 post-operative (PO) days. On PO day 7, the patient presented with abdominal distension, elevated inflammatory indices, and fever, so we performed abdominal CT with oral and intravenous contrast looking for signs of intestinal obstruction.

The clinical hypothesis of obstruction was confirmed by the presence of numerous dilated small bowel loops with air/fluid levels; CT showed an ileum segment trapped in the sacral fracture [Figure 3].

Figure 3

Cross-sectional CT image of the abdomen. The white vertical arrow indicates small bowel loops with air/fluid levels. The white horizontal arrow shows the ileum segment trapped in the sacral fracture

The patient underwent an exploratory laparotomy that confirmed the cause of the obstruction; a small bowel resection and an end-to-end manual anastomosis were thus performed.

The second post-operative period was uneventful, and the patient was discharged from the ICU to a ward. An evaluation of the rectal sphincter showed normal function; therefore, after the peroneal wound healed, the colostomy was closed.

DISCUSSION

Hemorrhage resulting from pelvic disruption remains a significant potential source of mortality. Injured arteries, veins, and bony structures are all likely sources of blood loss. The relative contribution of each of these components is unknown. Angio-embolization is the accepted method for treating arterial bleeding, while reduction and stabilization with external fixation or other methods are considered the most appropriate for controlling blood loss from veins and bony surfaces.

The risk of hemorrhage makes major pelvic fractures one of the most serious skeletal injuries, with substantial mortality. In addition, pelvic fractures are often associated with other major injuries, which can contribute to an increased mortality. The mortality following pelvic fractures has declined radically since introduction of more effective methods of controlling hemorrhages and general trauma management.[2]

Hemorrhage control, fracture stabilization, and infection prophylaxis in cases of open fracture can be achieved with the placement of Schanz screws.[1] Post-traumatic bowel entrapment was first described in 1907.[3] Since then, there have been only occasional reports in the literature. In a literature review, Stubbart and Merkley documented 19 similar cases.[4] Five of these 19 died from sepsis. The diagnosis of entrapment is often difficult and delayed. With the introduction of multi-detector CT and the associated reformatting capabilities, the diagnosis of this complication should be more accurate.

Patients with pelvic fractures and disruptions have usually sustained high-energy trauma and have myriad other possible reasons for symptoms of ileus, obstruction, perforation, or intra-abdominal problems. Bowel injury associated with pelvic fractures or the surgical treatment thereof is relatively rare and is consequently not always ranked highly in the differential diagnosis.

As with our case, most cases of distension and nausea post-pelvic fracture are thought to be due to adynamic ileus and not to mechanical obstruction. Adynamic ileus complicates as much as 18% of pelvic fractures.[5] This complication is due to retroperitoneal hematoma. Hurt et al. stated that such ileus usually lasts 5 days, but can persist longer than 2 weeks.[6]

Reported cases of bowel entrapment in pelvic fractures, especially in sacral fractures, are exceedingly rare. In most situations, the iliac and psoas muscles serve as buffers between the abdominal contents and posterior pelvic ring injury, protecting the peritoneum from injury and preventing the bowel from communicating with the fracture site. Although accurate prediction and prevention of this type of complication might be impossible, earlier recognition and proper treatment are reasonable ways to obtain good results. The diagnosis is often delayed due to the difficulty distinguishing entrapment from the more common adynamic ileus.

Therefore, all general surgeons who care for patients with pelvic injuries should be conscious of this potential complication and consider it in their workup of patients with post-operative abdominal symptoms after major pelvic trauma or subsequent pelvic surgery, especially in patients treated with a percutaneous technique that prevents direct visualization of the fracture and abdominal or pelvic contents.

CONCLUSIONS

In conclusion, clinicians and radiologists should be aware of this potentially lethal complication of pelvic fractures treatment. To exclude bowel entrapment, patients with a persistent ileus or sepsis should undergo computed tomography promptly.