Regarding the pathophysiology of death in hanging, all of the following mechanisms contribute to asphyxia EXCEPT:

Explanation

## Pathophysiology of Hanging Deaths ### Primary Mechanisms of Death **Key Point:** Hanging causes death through multiple overlapping mechanisms, but spinal cord transection is NOT a typical mechanism in most hanging cases. #### Mechanisms That DO Occur in Hanging: 1. **Carotid Artery Compression** - Occurs at relatively low pressures (2–3 kg force) - Leads to cerebral ischemia within seconds - Most common mechanism in judicial/typical hangings 2. **Airway Obstruction** - Compression of the larynx and trachea by the ligature - Prevents air entry into the lungs - Contributes to hypoxia and hypercapnia 3. **Vagal Inhibition (Carotid Sinus Reflex)** - Sudden pressure on the carotid sinus triggers the vagus nerve - Causes bradycardia, hypotension, and sudden cardiac arrest - Can occur within seconds, even with minimal ligature pressure - Explains "instantaneous" deaths in some hangings #### Why Cervical Vertebral Fracture Is NOT Typical: **Warning:** Spinal cord transection with vertebral fracture is characteristic of **judicial hanging** (with a calculated drop and noose placement) — a rare form of execution. In typical suicidal or accidental hangings, the drop is insufficient to cause fracture-dislocation. **High-Yield:** In most hanging deaths (>90% of cases): - The drop is short or absent (feet may touch ground) - Vertebral fracture does NOT occur - Death results from carotid compression, airway obstruction, or vagal inhibition - Spinal cord injury is NOT a primary mechanism ### Comparison Table: Hanging vs. Strangulation | Feature | Hanging | Strangulation | | --- | --- | --- | | **Carotid compression** | Yes (main) | Yes (main) | | **Airway obstruction** | Yes | Yes | | **Vagal inhibition** | Yes | Yes | | **Vertebral fracture** | Rare (judicial only) | Never | | **Ligature marks** | Single, inverted V | Usually bilateral, horizontal | **Clinical Pearl:** The presence of a vertebral fracture in a hanging victim should raise suspicion for judicial execution or a very high drop — uncommon in modern forensic practice. ### Key Distinction **Mnemonic — CAV (Mechanisms of Hanging Death):** - **C**arotid compression (most common) - **A**irway obstruction - **V**agal inhibition (carotid sinus reflex) Spinal cord transection is **NOT** part of the typical CAV triad and occurs only in judicial hangings with calculated drops.