Case Report
A 70-year-old woman underwent an L4–L5 lumbar arthrodesis procedure without immediate complications. On the fourth post-operative day, however, she presented with painful swelling of the left lower limb. Given the recent surgery and immobilization, deep vein thrombosis (DVT) was suspected, and a Doppler ultrasound was performed. However, the ultrasound did not reveal any radiologic signs of DVT (Figure 1).
Figure 1
Doppler ultrasound of the left lower limb without signs of DVT.
Due to the lack of evidence for DVT, a contrast-enhanced computed tomography (CT) scan was performed, which revealed an arteriovenous fistula (AVF) involving the left common iliac vessels (arrow in Figure 2).
Figure 2
Angio-CT revealing an arteriovenous fistula involving the left common iliac vessels.
The lumbar arthrodesis screws were visualized, and an irregularity of the left common iliac vein was noted, suggesting laceration (arrow in Figure 3, A). In the arterial phase, the iliac arteries and the left common iliac vein demonstrated intense enhancement, while the right common iliac vein showed normal mild enhancement (circle in Figure 3, B). The left lower limb was significantly swollen with subcutaneous edema, and contrast enhancement in both the femoral artery and vein was apparent, unlike in the contralateral leg, which showed no contrast in the right femoral vein (dashed arrow in Figure 3, C).
Figure 3
CT revealed arterial opacification of the left femoral vein and a swollen left lower limb.
Subsequently, an aortic arteriography was performed, confirming the AVF with early filling of the left common iliac vein through the ipsilateral common iliac artery. Covered stents were successfully placed to treat the AVF, with good angiographic results. The patient recovered without complications and was discharged three days later.
Comment
While deep vein thrombosis is a common concern in the post-operative setting, rare complications such as iatrogenic arteriovenous fistula can present with similar symptoms. Similar vascular complications have been reported in spinal procedures such as intervertebral disc surgery or lumbar reconstruction, but their incidence is very low, particularly with a posterior approach [1]. This case highlights an exceedingly rare complication following a posterior-approach lumbar arthrodesis, which, to our knowledge, has not been previously described. The clinical presentation of such an AVF can mimic that of DVT, underscoring the importance of considering a broad, differential diagnosis in post-operative patients.
Competing Interests
The authors have no competing interests to declare.