Pseudoaneurysm of the Deep Femoral Artery after Pertrochanteric Hip Fracture: A Case Report

Abstract

Hip fractures are a common injury among the elderly. A quarter of all pertrochanteric fractures are unstable with a fractured lesser trochanter. Most of these fractures are treated with an intramedullary fixation. We report a rare complication of pseudoaneurysm formation of the deep femoral artery due to migration of the lesser trochanter after intramedular repair with the Gamma 3 Locking Nail. The patient was subsequently treated with resection of the bone fragment and reconstruction of the deep femoral artery with an autologous vein. The patient recovered well and was able to return to normal daily activities.

VASCULAR DISEASE MANAGEMENT 2011;8:E119–E120

Keywords: pseudoaneurysm; deep femoral artery; pertrochanteric hip fracture; Gamma Nail

Introduction

Hip fractures are common in the elderly population. The lifetime risk of hip fracture is about 18% in women and 6% in men.¹ Treatment of choice for a pertrochanteric femur fracture in our hospital is an intramedullary fixation using the Gamma 3 Locking Nail (GN-3; Stryker, Mahwah, New Jersey) or the extramedullary sliding hip screw fixation (DHS; Synthes GmbH, Oberdorf). If there is a fractured lesser trochanter (AO type 31 A2), it is usually not fixated during this procedure because of the difficulty of fixating this piece of bone and the supposed absence of complaints afterwards. As a consequence the lesser trochanteric bone is able to displace due to traction of the iliopsoas muscle (flexion of the hip) after surgery. In the literature, numerous reports of complications of this intramedullary fixation technique are described but most of them handle problems related to the device itself. Vascular injuries related to the pertrochanteric fracture are described in relation to the trauma itself, during surgery or in the postoperative period due to dislocation of a bony fragment. Only a few reports are found about the latter type and all describe injuries after intertrochanteric fractures.^2-5

We report a patient who developed a false aneurysm of the deep femoral artery after fixation of a pertrochanteric hip fracture AO type 31 A2 using the Gamma 3 Locking Nail.

Case Report

An 82-year-old vital woman presented at our emergency department after she fell off her bike onto her left hip. On clinical examination we found an elderly but otherwise healthy patient with no relevant previous medical history. X-rays of the pelvis and left hip revealed a pertrochanteric femur fracture with a dislocated lesser trochanter (Figure 1). An osteosynthesis was performed the next day using the intramedullary Gamma 3 Locking Nail. Postoperative recovery was uneventful and she was discharged for further revalidation on the seventh postoperative day. After an initial 2 weeks of partial weight bearing she visited our outpatient clinic for a routine postoperative control. The X-ray demonstrated a medial and anterior dislocation of the lesser trochanter (Figure 2). Clinical examination showed a resolving hematoma of the left hip and no signs of neurovascular complications. Instructions for further mobilization with full weight bearing were given.

Five days later she presented to our emergency department with pain, tenderness, edema of the upper leg and signs of inflammation at the site of the hematoma. There were no signs of abscess formation. A mild soft tissue infection was suspected and she was discharged with broad-spectrum antibiotics and compression therapy. Further follow up was done at our outpatient clinic, the signs of infection and the edema diminished. The fifth postoperative week she mentioned a painful swelling in the left groin. On clinical examination we found a pulsatile swelling in the left groin. Echographic examination showed a pseudoaneurysm of the deep femoral artery. For further diagnosis a CT angiography scan was performed (Figure 3).

We decided to perform an open reconstruction of the artery and resection of the lesser trochanter. After vascular control was established we opened the pseudoaneurysm of the deep femoral artery. The sharp fragment of the lesser trochanter perforated the wall of the artery (Figure 4). The sharp fragment was resected as well as the pseudoaneurysm and a venous reconstruction using the greater saphenic vein was performed. Further postoperative recovery was uneventful and she was discharged on the fifth postoperative day.

Discussion

False aneurysms after trochanteric fractures are a rare complication with a reported incidence of 0.21 percent.⁶ Most of these injuries are due to iatrogenic trauma or the trauma itself and rarely by dislocated bone fragments.⁴ In this case the anteriorly displaced lesser trochanter caused the false aneurysm by perforating the deep femoral artery wall. Displacement of this fragment with subsequent vascular injury is caused by mobilization after surgery due to the insertion of the iliopsoas muscle (flexion of the hip) on the lesser trochanter. A false aneurysm is difficult to recognize after hip surgery because of non-specific symptoms such as pain, swelling, anemia and hematoma; all of these symptoms are usually present after hip surgery. In retrospect, considering the extreme anterior dislocation of the sharp lesser trochanter, the diagnosis of a pseudoaneurysm might have been considered earlier. There should be a high index of suspicion of a pseudoaneurysm if there is a progressive (pulsatile) swelling in the groin and a continuous need for blood transfusion. The investigations of choice are a duplex ultrasound followed by CT angiography. The treatment depends upon the anatomical features and findings. Treatment options for a pseudoaneurysm consist of thrombin injection, open or endovascular repair. Due to the specific character of the described injury we think that an open repair with resection of the bone fragment is the only definite treatment. Depending on the size of the aneurysm and hemodynamics of the patient either an urgent or elective repair should be performed.

Conclusion

A false aneurysm due to a dislocated lesser trochanter after pertrochanteric femur fracture is rare and difficult to diagnose due to the non-specific symptoms. CTA or duplex are the preferred diagnostic techniques and should be used for further operative planning. Open surgery with resection of the bone fragment and arterial reconstruction is the only definite treatment.

References

1. Gillespie WJ. Extracts from “clinical evidence”: Hip fracture. Brit Med J 2001 Apr 21;322:968­­–975.
2. Abraham E, Pankovich AM, Jansey F. False aneurysm of the profunda femoris artery resulting from intertrochanteric fracture. A case report. J Bone Joint Surg Am 1975;57:871.
3. Mauerhan DR, Maurer RC, Effeney D. Profunda femoris arterial laceration secondary to intertrochanteric hip fracture fragments: A case report. Clin Orthop Relat Res 1981;161:215–219. 
4. Murphy PG, Geoghegan JG, Austin O, et al. Pseudoaneurysm of the profunda femoris artery due to intertrochanteric fracture of the hip. Arch Ortho Trauma Surg 1999;117–118.
5. Kizilates U, Nagesser SK, Krebbers YMJ, et al. False aneurysm of the deep femoral artery as a complication of intertrochanteric fracture of the hip: Options of open and endovascular repair. Perspect Vasc Surg Endovasc Ther 2009;21:245–248.
6. Karanikas I, Lazarides M, Arvanitis D, et al. Iatrogenic arterial trauma associated with hip fracture surgery. Acta Chir Belg 1993;93:284–286.

___________________________________

From Amphia Hospital, Breda, the Netherlands.
The author reports no conflicts of interest regarding the content herein.
Manuscript submitted December 20, 2010 and accepted January 5, 2011.
Address for correspondence: Jack N. Helleman, MD, Amphia Hospital Surgery, Molengracht 21 Breda, 4818 CK, The Netherlands. Email: jackhelleman@yahoo.com