Complex sentence: In a deep vein thrombosis (DVT), or in a superficial thrombosis where the thrombus is floating, especially if it is located near to the sapheno-femoral junction will indicate an emergency situation since their will be a high risk of a pulmonary embolism occurring.
Split into simpler sentences: In a deep vein thrombosis (DVT), or in a superficial thrombosis where the thrombus is floating, an emergency situation will be indicated. If the thrombus is near to the sapheno-femoral junction there will be a high risk of a pulmonary embolism occurring.