A 32-year-old man is brought to the emergency department with a gunshot wound to the left anterior chest at close range. On examination, he has an entry wound measuring 0.8 cm with a surrounding abrasion collar and a stellate laceration pattern around the wound margin. There is soot and powder residue visible on the skin. Chest X-ray reveals a pneumothorax and mediastinal widening. What is the most likely range of fire for this injury?

Explanation

## Diagnosis: Contact/Near-Contact Firearm Injury ### Key Features of the Wound **Key Point:** The presence of soot (unburned powder particles) and powder residue (burned gunpowder) on the skin around the entry wound is pathognomonic for close-range fire. **High-Yield:** The range of fire in gunshot wounds is determined by: 1. **Entry wound characteristics** (size, abrasion collar, stellate lacerations) 2. **Soot deposition** (blackening of skin and clothing) 3. **Powder tattooing** (stippling or peppering from unburned powder grains) 4. **Singeing of hair and clothing** (indicates heat from muzzle flash) ### Range Classification Table | Range Category | Distance | Entry Wound | Soot | Powder Tattooing | Singeing | |---|---|---|---|---|---| | **Contact** | Muzzle on skin | Stellate laceration, soot, soot inside wound tract | Present | Absent | Present | | **Near-contact** | 0–15 cm | Small entry, abrasion collar, soot visible | Present | Absent | May be present | | **Intermediate** | 15 cm–1 m | Entry wound, abrasion collar, NO soot | Absent | Present (stippling) | Absent | | **Distant** | >1 m | Small entry, abrasion collar only | Absent | Absent | Absent | ### Clinical Correlation In this case: - **Soot and powder residue** = fired within 15 cm - **Stellate laceration pattern** = contact or near-contact (tissue stretching from muzzle blast) - **Abrasion collar** = present but secondary to soot/laceration findings - **Mediastinal widening** = suggests major vessel injury (aorta or great vessels), consistent with close-range high-velocity trauma **Clinical Pearl:** Soot can be wiped off and may not always be visible on initial inspection; powder tattooing (stippling) is permanent and cannot be wiped away. The absence of tattooing here, combined with visible soot, confirms close range. **Warning:** Do not confuse soot (black residue from incomplete combustion) with powder tattooing (small abrasions from unburned powder grains). Soot indicates closer range than tattooing.