The incidence of acute venous injury as a result of proximity penetrating trauma screened with colour flow duplex ultrasound.

The incidence of acute deep venous thrombosis as a result of penetrating proximity extremity trauma (PPET) to the thigh has been demonstrated to be 16% in a single report. The purpose of the current study is to demonstrate the incidence and clinical significance of venous injury as a result of proximity trauma to the thigh in a large cohort screened with colour flow duplex (CFD) ultrasound and to identify factors predictive of defining a wound in proximity to a major vascular structure. A prospective observational study was conducted from January 1st, 2010 to January 1st, 2012 on all patients presenting with penetrating extremity trauma. Data on injury location, mechanism, associated extremity and non-extremity injuries, use and results of CFD, as well as the admitting trauma surgeon were recorded and analysed. 220 thigh wounds with a normal physical examination were identified, of which 167 (75.9%) underwent CFD due to proximity. The incidence of acute venous injury was 4.8% (8/167). 37.5% (3/8) of these injuries resulted in morbidity. Injury mechanism and which attending physician was on call were predictive of a wound being defined as in proximity, whereas an injury with an associated fracture was a negative predictor. Occult venous injuries as a result of PPET occur in 4.8% of patients with thigh wounds in proximity to a major vascular structure. The designation of a wound as being in "proximity" was influenced by injury mechanism, associated fractures, and the judgement of the on-call attending. Colour flow duplex is a valuable tool with the ability to identify not only occult arterial injuries, but also venous injuries with the potential to cause significant morbidity as well.