Forensic Pathology Quiz 6

Explanation
The severity, extent, and appearance of injuries due to blunt force trauma depend on multiple factors. The amount of force delivered to the body plays a role in determining the extent of the injury. The time over which the force is delivered can also impact the severity of the injury. The region struck on the body can determine the specific injuries sustained. The amount of body surface over which the force is delivered can also affect the extent of the injuries. Finally, the nature of the weapon used in the blunt force trauma can also contribute to the severity and appearance of the injuries. Therefore, all of the factors mentioned above can influence the outcome of injuries caused by blunt force trauma.

Explanation
Abrasions are skin injuries caused by the removal of the superficial epithelial layer due to friction against a rough surface or by compression. This can occur when the skin rubs against a rough object or is pressed against a hard surface. Unlike contusions, lacerations, and fractures, which involve different types of injuries to the skin or underlying structures, abrasions specifically refer to the removal of the superficial layer of the skin.

Explanation
Brush abrasion occurs when a blunt object scrapes off the superficial layers of the skin, leaving a denuded surface. This type of abrasion is characterized by a brushing or sweeping motion, rather than a direct impact or patterned scraping.

Explanation
Abrasions are superficial injuries that only affect the top layers of the skin. Since they do not penetrate deep into the skin, they typically heal without leaving a scar. This is because the body's natural healing process involves regenerating new skin cells to replace the damaged ones. However, if the abrasion is severe or becomes infected, it may take longer to heal and could potentially result in scarring.

Explanation
Contusions, or bruises, are caused by blunt force trauma to the body, resulting in damaged blood vessels and discoloration of the skin. They can occur in any area of the body, regardless of the thickness of the skin. Therefore, the statement that contusions are more readily incurred in areas with thick skin is false.

Explanation
Spectacle hematomas, also known as Racoon Eyes, refer to contusions that occur around the soft tissues surrounding the eyes. This statement is true because it accurately describes the nature of spectacle hematomas. These contusions are typically characterized by bruising and discoloration around the eyes, resembling the appearance of a raccoon's eyes.

Explanation
The given statement is false. The photo labeled "face-2.jpg" does not show a woman who sustained blunt force trauma to her eyes.

Explanation
The correct answer is "impact/pressure abrasions". This type of blunt force trauma is commonly seen over the eyebrows, cheekbones, and nose when an unconscious person collapses. It is caused by the impact and pressure exerted on the face during the fall, resulting in abrasions.

Explanation
Scab formation is the first stage of abrasion healing that indicates the person likely survived for at least four to twelve hours following a blunt force injury. Scab formation occurs when platelets in the blood clump together to form a clot, which then hardens and forms a protective layer over the wound. This process helps to prevent further bleeding and infection, allowing the healing process to begin. Scars, on the other hand, are formed during the later stages of healing and are not indicative of the initial survival timeframe.

Explanation
The statement is false because the initial appearance of an abrasion is not dark blue, purple, or crimson. Abrasions typically appear as red or pink in color due to the damage to blood vessels. As the healing process continues, the color may change to yellow or brown before it eventually fades away.

Explanation
The statement suggests that the color of a healing contusion can accurately determine its age. However, this is false. While the healing rate for contusions may be relatively constant, the color of a bruise alone is not a reliable indicator of its age. Factors such as the individual's skin tone, the severity of the injury, and the location of the bruise can all affect the color and appearance of a healing contusion. Therefore, it is not possible to accurately estimate the age of a bruise based solely on its color.

Explanation
The statement is false because the size and severity of a contusion can be indicative of both the amount of force applied and the location of the impact. The force applied is one factor that can determine the size and severity of a contusion, but the location of the impact can also play a role. For example, a contusion on a bony area may be smaller but more severe compared to a contusion on a softer area. Therefore, the size and severity of a contusion are not solely indicative of the amount of force applied.

Explanation
Contusions, which are bruises, typically occur as a result of injury before death. This is because contusions are caused by blunt force trauma to the body. However, in rare cases, it is possible for contusions to be made postmortem if a severe blow is delivered within a few hours of death. This can happen because the blood vessels in the body may still be fragile and susceptible to rupture shortly after death. Therefore, the statement that contusions usually indicate injury before death is true.

Explanation
Lacerations of the skin are typically characterized by irregular edges with abraded and contused (bruised) margins. This means that when the skin is torn or cut, the edges of the wound are not smooth and may have scrapes or bruises around them. This is a true statement as it accurately describes the characteristics of lacerations.

Explanation
Long objects tend to make linear lacerations, while flat objects tend to make irregular or Y-shaped lacerations.

Explanation
Bridging of a wound refers to the presence of a raised ridge or bridge of tissue within the wound. This is commonly seen in lacerations caused by blunt force trauma, such as a fall or a punch. Sharp force injuries, on the other hand, typically result in clean, straight-edged wounds without any bridging. Therefore, the statement that bridging of a wound is indicative of a sharp force injury is false.

Explanation
An avulsion is a type of laceration because it involves the tearing or pulling away of tissue or skin from the body. Lacerations are cuts or tears in the skin, and an avulsion specifically refers to a situation where a portion of skin or tissue is completely separated from the body. Therefore, an avulsion can be considered a type of laceration.

Explanation
Fractures are indeed disruptions in the continuity of a bone caused by external force. When a fracture occurs, it is usually visible on a radiological exam as a linear lucency, indicating a break in the bone. Therefore, the statement is true.

Explanation
Fractures can indeed be caused by either direct or indirect force to the bone. Direct force fractures occur when there is a direct impact or blow to the bone, causing it to break. Indirect force fractures, on the other hand, occur when there is a force applied to the bone at a distance away from the fracture site, causing the bone to break. Therefore, it is true that fractures can be caused by either direct or indirect force to the bone.

Explanation
A compound fracture is a type of fracture where the bone breaks through the skin. It is also known as an open fracture. The number of breaks in the bone is not relevant to the classification of a compound fracture. Therefore, the statement that a compound fracture is one in which there are three or more breaks in a bone is false.

Explanation
Transverse fractures of the sternum can occur as a result of the force applied during CPR. CPR involves chest compressions which can be quite vigorous, especially when performed on someone with a fragile or weakened sternum. The force exerted during CPR can cause the sternum to fracture in a transverse direction. Therefore, it is true that transverse fractures of the sternum may be caused by the administration of CPR.

Explanation
A massive crushing force to the chest can cause laceration of the pericardium, which is the protective sac surrounding the heart. This can occur due to the extreme pressure applied to the chest, leading to tearing or rupture of the pericardium. This can result in serious complications such as cardiac tamponade, where blood or fluid accumulates in the pericardial sac, putting pressure on the heart and impairing its ability to function properly. Therefore, the statement is true.

Explanation
The statement is true because lungs are generally able to withstand compression without getting injured. However, a sudden and forceful blow to the chest can result in a lung contusion, which is a bruise on the lung tissue. This injury can occur due to trauma, such as a car accident or a fall, and can cause symptoms like chest pain, difficulty breathing, and coughing up blood. Therefore, it is important to be cautious and protect the chest area from any forceful blows to prevent lung contusions.

Explanation
The absence of external injuries to the abdomen does not necessarily indicate the absence of serious internal injuries to the tissue or organs contained in the abdomen. Internal injuries can occur without any external signs of trauma, and it is possible for serious damage to occur internally even if there are no visible injuries on the outside. Therefore, the statement is false.