A 13-year-old girl suffered fracture of her left clavicle. A figure-of-8 bandage was placed during initial treatment. Six days after trauma her distal arm, elbow and proximal forearm were swollen, pain and tenderness of distal part of brachial vein was recognized during clinical examination. Duplex ultrasonography revealed partial thrombosis of the brachial vein. Bandage was immediately removed and administration of LMWH (enoxaparin) was started. Complete recanalization was achieved after a few days. The fracture was healed without further complication, patient was without sonographic and clinical signs of post-thrombotic syndrome. The second case report describes a 14-year-old boy. Initially, the fixation was a figure-of-8 bandage. 5 days after the injury he had swollen arm and elbow on the injured side, according to duplex ultrasonography deep venous thrombosis of the axillary and the brachial vein was recognized. There was only partial recanalization at the first sonographic follow up, the patient was converted to Warfarin for 3 months after injury after initial LMWH therapy. At the last follow-up, fracture of the left clavicle was healed and there were no DUSG or clinical signs of post-thrombotic syndrome.