1. Sharp-Force Trauma (Obj 7.3)
Sharp-force trauma—when the victim is poked, cut, or stabbed by something sharp
Stab Wounds
Incised Wounds
Chop Wounds
Therapeutic Wounds
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

2. Stab Wounds
Most are caused by single-edged kitchen, pocket, or folding knives
Blade is usually 4-5 inches long
A sharp knife requires very little force
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

3. Stab Wound: Single Edge Blade
Sharp edge of blade
This is a stab wound with a single edge blade. Note the sharp point of the blade at the left and the notch of the opposite side of the knife at the right. The shape of stab wounds can vary considerably, depending upon whether the incision is along the axis of, or perpendicular to, Langer's lines. Those perpendicular will tend to pull apart and gape open, while those parallel to the lines of stress will tend to remain slit-like.

4. Stab Wounds
hesitation marks - jagged and rough superficial wounds caused by someone attempting to take their own life, caused as the person responds to the pain
Hesitation marks—by suicide victims
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

5. Stab Wounds Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

6. hilt - protective piece where the blade meets the handle of a knife
Penetrating wound—puncturing the organ
Perforating wound—passes all the way through the organ
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

7. Incised Wounds incised wounds - cuts along the surface of the body.
Produced by sharp-edged objects such as knife, glass, metal, or paper
Longer than deep
Force usually applied parallel to the skin
Do not provide clues to the type of weapon
Clean edges
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

8. Chop Wounds
chop wound - wounds that result in cuts (incised wounds) on the surface and deep internal injuries and/or fractures to bones
Heavy tools—axes, machete, meat cleavers
Incised wounds on the surface
Deep internal injuries
Bone fractures
Characteristics of the wound help narrow down the possible type of weapon used
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

9. Chop Wounds Weapon Characteristics Axe
Often crushes the bone and tissue
Machete
Produce more obvious lines that are coarse and less distinct
Meat Cleaver
Clean thin wound; unlikely to break bone; thin, sharp lines on the bone
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved

10. Therapeutic Wounds Caused by surgery or other medical procedures
Avoid confusion between therapeutic and inflicted wounds
Inflicted wounds are criminal wounds like stab wounds
Forensic Science II: Physical Trauma, Chapter 7
© 2012 Cengage Learning. All Rights Reserved