Chest impact experiments aimed at producing aortic rupture.
There are a number of proposed mechanisms of traumatic aortic rupture. These experiments involved three different chest impacts that may be associated with aortic rupture. Eleven unembalmed cadavers were repressurized and impacted by a 24-34 kg mass at 8.6-14.9 m/sec. Three impact orientations were studied with the torso axis: (1) 30-45° up from horizontal and impact 28-45° clockwise of the midsagittal axis, (2) 105-130° up from horizontal and impact 15° counterclockwise, and (3) 75° up from horizontal and impact 15° counterclockwise. Spinal acceleration was measured at T1, T8, and T12 and chest compression was determined by high-speed video. Detailed autopsy determined injuries. Impact loads averaged 9.65 ± 2.45 kN and resulted in 52.8 ± 5.4% chest compression and 3.53 ± 0.94 m/sec Viscous response. The resultant spinal acceleration was 124.5 ± 105.4 g at T1, 141.3 ± 80.5 g at T8 and 89.3 ± 39.1 g at T12. The severity of impact resulted in multiple rib fractures and severe chest injury averaging AIS = 4.2 ± 1.0. There were four cases of heart laceration and one transection of the ascending aorta 20 mm from the cusp of the aortic valve. The impacts were severe enough that aortic rupture was expected; however, only one occurred. In retrospect, the position of the heart and aorta in the upright cadaver may not have been representative of the position during human injury, thus reducing the incidence of aortic rupture in these experiments.
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Viano
D000054:Acceleration / Q000009:adverse effects*; D000328:Adult; D000368:Aged; D001011:Aorta / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology; D001019:Aortic Rupture / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D001837:Body Weights and Measures; D002102:Cadaver; D005260:Female; D006335:Heart Injuries / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D013898:Thoracic Injuries / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D014194:Traumatology / Q000379:methods*; D014949:Wounds, Nonpenetrating / Q000209:etiology*