Acute arterial injuries are often complicated by the development of an arteriovenous fistula (AVF). In the acute setting, an AVF may present at the same time as the arterial injury. A case of traumatic AVF in the thigh that presented with normal neurovascular examination findings is reported. AVF was diagnosed by duplex scan and managed promptly. The authors suggest that duplex imaging together with arteriography, where appropriate, should be performed routinely when penetrating wounds are in close proximity to major vessels despite a normal clinical neurovascular examination.