The brachial artery is rarely injured after closed dislocation of the elbow. We describe an unusual variation of this injury, namely, a delayed thrombosis of the brachial artery after a closed dislocation sustained during a low-energy fall. This has not previously been described in the English literature, but may be more common than this suggests. We stress the importance of a thorough neurovascular examination and vigilance in regard to this potentially disastrous complication.