Is variation in posterior tibial veins a risk factor for deep-vein thrombosis?

Introduction: This study proposes variations in the posterior tibial vein as one of the risk factors for deep-vein thrombosis. Understanding the anatomical classification of the posterior tibial vein would guide the antegrade approach of catheter-directed thrombolysis. Materials and methods: One hundred thirty-four legs from Korean and Thai cadavers were dissected. The posterior tibial veins were classified into four types according to the number of proximal and distal veins. Results: The most common type was type Ia (64/134), followed by type IIa (28/134), type Ib (24/134), and type IIb (16/134). Conclusions: The anterior tibial and fibular veins had exactly two paired veins; however, the posterior tibial vein had many variations. We assume that patients with type IIb and IIa have a higher risk of thrombosis and hidden symptoms due to collateral formation. Additionally, the classification of the posterior tibial vein and dividing into proximal and distal posterior tibial vein would help practitioners predict the course and guide the application of catheter-directed thrombolysis.