ABMDI: Injuries and Artifacts with 100% correct answers

What are the 3 types of trauma? 1. Blunt force 2. Sharp force 3. Thermal injuries What is blunt force trauma? What are the 3 most common effects? Impact of a blunt object against the skin. The three types are contusion, abrasion, and laceration Contusion v Abrasion v Laceration Contusion: Creates purple color from crushing the tissue and tearing small blood vessels Abrasion: Scraping of superficial skin layer by friction Laceration: Tearing of skin and soft tissue (abraded skin surrounds tear and has irregular edges) Laceration v Incision Laceration: Found with blunt injuries Incision: Found with sharp injuries Incisions Clean cuts that characterize sharp-force injuries Stab wound Sharp-force injury. Incision that is deeper than it is wide Defensive wound Cutting wounds on the backs of forearms, arms, hands, or palms where it looks like the victim tried to grab blade Hesitation mark vs Hilt mark (what does this inidicate) Hesitation: Cutting wounds to the wrist Hilt: Abrasion near the stab wound, likely from the knife handle. Indicates the knife was forced in entirely Injuries typically sustained by a driver in an MVA? (6) Horizontal laceration to forehead, knee abrasions, sternal contusions, "dicing" injuries to left side of the face, seatbelt abrasion from L-R, and fractures/abrasions Injuries typically sustained by front passenger in MVA? (4) Horizontal laceration to forehead, knee abrasions, "dicing" injuries to right-side of the face, and seat belt abrasion from R-L Why do MEIs see "ice cube" or "dicing" injuries in MVAs? Due to the tempered glass on side windows fracturing into "ice cube" shapes Injuries to motorcycle drivers in an MVA? (2) Confluent abrasions and other nonspecific injuries What injuries do pedestrians have when hit by a car? (3) Contusions, crushing injuries to the lower body, and patterned injuries from tires Bumper injuries Crushing injuries to lower legs and fractures Closed vs open fractures Closed: intact skin Open: Laceration of overlying skin What patterns are demonstrated by skull fractures? Linear or line-like depressions and indentations What can a fracture of the internal front skull cause? (1) What can that look like? Hemorrhage or ecchymosis surrounding the eyes. It looks like raccoon eyes What can result from a skull fracture at the base of the brain? Bleeding from the ears 4 classifications of burn injuries 1st, 2nd, 3rd, and 4th degree burns Describe the damage of 1st, 2nd, 3rd, and 4th degree burns 1st: Superficial/sunburn 2nd: Damage to upper skin layers (blister) 3rd: Deep and through entire skin (requires graft) 4th: Severe tissue charring When analyzing burn victims, how do we estimate survival chances? Sum of individual's age and % of total skin area burned What method is used to estimate the % of body burned? Rule of 9 What % of body burned is fatal for each age demographic? Children and elderly Healthy adults Children and elderly: 20% Healthy adults: 50% How can an autopsy determine if someone was alive during a fire? Identification of soot in the airway Appearance of body and symptoms from CO poisoning. (5) 1. Cherry-pink coloration 2. Headache 3. Vomiting 4. Fainting 5. Death 4 possible conditions of bodies recovered from fires. 1. CO poisoning 2. Burst skull 3. Extremity fractures 4. Abdominal perforations What is asphyxia? What are the 5 types? Lack of O2 and excess CO2 in the tissues. Strangulation, aspiration, mechanical asphyxia, positional asphyxia, and drowning What is aspiration? Inhalation of foreign object that obstructs/occludes the airway. Strangulation. 2 causes of it. Compression of the neck, obstructing air or blood. 1. Object encircling the neck 2. Direct pressure Petechial hemorrhage Small pinpoint hemorrhag