Duplex Ultrasound Scan Can Prevent Leg Amputation in Severe Postthrombotic Syndrome: A Case Report

<b>Introduction:</b> Postthrombotic syndrome (PTS) describes a condition arising after an acute deep venous thrombosis (DVT) that is characterised by leg heaviness, discomfort, and recurrent venous ulceration. Venous disease is associated with significant morbidity and impairment of mobility due to pain, infection, and oedema. <b>Report:</b> We present a patient in his 40s attending with left lower limb ulceration, swelling, and refractory pain despite previous best medical management and superficial radiofrequency ablation. A venous duplex ultrasound revealed a trifid femoral vein with a competent and incompetent component. Venography showed patent deep veins but failed to offer the same level of detail as duplex. The patient underwent a femoral vein ligation after multidisciplinary discussion. The role of intraoperative duplex ultrasound was essential. The patient clinically improved and is now free of his venous ulcerations. <b>Conclusion:</b> Duplex provided vital information for surgical planning, which venogram was unable to offer. This is an imaging pitfall that is important to be aware of in patients presenting with recurrent venous disease. Our case highlights the importance of thorough clinical assessment and the value of the Doppler ultrasonography assessment in confirming venous incompetence.