Hanging - Forensic Medicine Examination Answer

1. Causes of Death in Hanging (4 marks)

1. Asphyxia - The ligature forces the root of the tongue against the posterior wall of the pharynx and folds the epiglottis over the entrance of the larynx, blocking the airway. A weight of about 15 kg (33 lb) is required to compress the trachea sufficiently to produce asphyxia.
2. Venous congestion (Cerebral venous obstruction) - Jugular venous flow can be stopped with as little as 2 kg (4.4 lb) of pressure on the neck. This leads to venous engorgement, raised intracranial pressure, and cerebral anoxia.
3. Cerebral ischemia (Carotid artery occlusion) - Carotid arteries require only 4-5 kg (11 lb) to stop blood flow, while vertebral arteries require ~30 kg. Since the weight of the head alone (about 5-6 kg) is sufficient to occlude the carotids, death can occur even in partial hanging.
4. Vagal inhibition (Reflex cardiac arrest) - Pressure on the carotid sinus stimulates vagal afferents and causes reflex cardiac arrest.
5. Fracture-dislocation of cervical vertebrae - Rare in suicidal/nonjudicial hangings; occurs in judicial hanging due to the long drop, causing cord injury and ascending edema of vital medullary centers. In non-judicial settings it may occur with advanced osteoarthritis of the cervical spine.

• Aspiration pneumonia
• Hypoxic encephalopathy
• Pulmonary edema
• Encephalitis / cerebral abscess

2. Important Autopsy Findings (4 marks)

External Findings

1. Neck may be stretched and elongated; rarely severed if the fall is from great height
2. Head is bent to the side opposite the knot
3. Face is usually pale (due to arterial occlusion); may be congested/swollen if only veins are obstructed
4. Petechiae on skin and conjunctivae (Tardieu spots) - more marked when the noose is high in the throat
5. Eyes - protruded and firm due to congestion; pupils dilated
6. Tongue - swollen, protruding between lips; tip blackened by drying; may be clenched between teeth
7. Dribbling of saliva from the angle of the mouth down the chest - a classic indicator of antemortem hanging (caused by ligature stimulating salivary glands)
8. Drooping of semen from urethral meatus in males (post-mortem seminal emission)
9. Hypostasis over lower limbs and forearms - due to prolonged hanging posture; shifts to the back when the body is laid down
10. Involuntary passage of urine and feces

• A groove or furrow on the neck, classically oblique and upward-slanting toward the knot - does NOT completely encircle the neck
• Typically inverted-V shaped with the apex at the knot
• Pale, yellowish or yellow-brown ("parchment-like") due to drying of abraded skin
• In 80% of cases the mark is above the thyroid cartilage; in 15% at the level; in 5% below it
• Edges show a thin line of congestion or hemorrhage
• The width of the groove approximates the width of the ligature material
• Rope gives a deep, well-demarcated furrow with mirror-image weave pattern; soft materials (dupatta, scarf) may leave a poorly defined or absent mark

Internal Findings

1. Neck dissection findings (done after removing brain, heart and abdominal organs to allow a bloodless field):

• Tissues under the mark are dry, white and glistening
• Ecchymosis in neck muscles (sternomastoid, platysma) in ~10-15% of violent hangings
• Carotid artery - transverse tear of the intima (important vital reaction)
• Hyoid bone - fractured in 15-20% of cases; rare below age 40 due to cartilage elasticity; usually at the greater horn at the junction of inner 2/3 and outer 1/3
• Thyroid cartilage - fractured in 40-45% of cases; superior horn fracture or thyrohyoid ligament tear

1. Brain - Subarachnoid hemorrhage/effusions; congestion; hemorrhages from rupture of engorged vessels
2. Lungs - Congested; pulmonary edema; petechial hemorrhages over epiglottis, trachea and larynx (Tardieu spots internally)
3. Abdominal organs - Congested
4. Middle ear - Hemorrhages from rupture of small blood vessels
5. Absence of petechiae is common (>50%) because complete arterial occlusion prevents blood pooling in the head - so there is no pressure build-up

3. Incision Used for Neck Dissection in Autopsy (2 marks)

• The neck is NOT dissected first. The brain, thoracic and abdominal organs are removed first to drain blood from the neck vessels (Schrader's recommendation, 1940). The neck is then dissected in situ in a relatively bloodless field to avoid artefactual hemorrhage seeping into neck tissues and mimicking antemortem injury.
• The standard incision used to open the neck structures in autopsy is the Y-shaped incision extending to the neck, or more specifically a midline neck incision combined with the standard Y-shaped trunk incision, allowing layer-by-layer dissection of neck muscles, vessels, larynx, and cervical spine from front to back.
• In the Parikh/Dikshit approach for hanging: dissection proceeds layer by layer - skin, platysma, strap muscles, then larynx, hyoid, carotid sheaths, and finally vertebral column - always with the neck muscles examined in situ before being reflected.

4. Materials Preserved at Autopsy (2 marks)

5. Sexual Asphyxia (3 marks)

• The victim deliberately applies a noose around the neck, using transitory cerebral anoxia to intensify sexual gratification from masturbation
• Impaired circulation causes impaired consciousness, leading to hallucinations and feelings of erotic rapture
• The degree of asphyxia is controlled by mechanical means (e.g., tightening the noose by extending limbs, loosening it by flexing)
• Accidental death occurs when the control mechanism fails

• Victims are virtually always male (with occasional homosexual tendency or cross-dressing behavior)
• Abnormal sexual behaviors like masochism and transvestism may coexist
• Scene is usually the victim's own home (bedroom, attic)
• The hanging is typically partial/incomplete with feet on the ground, so the victim can relieve neck pressure by standing
• A stool or chair is found near the victim
• A pad between the ligature and neck is commonly used to prevent ligature mark

1. Evidence of abnormal sexual behavior (erotic/pornographic photographs, articles of female clothing, mirrors placed opposite the victim)
2. Evidence of previous attempts (old scars on the neck)
3. Evidence of padding between ligature and neck
4. No suicidal note
5. Evidence of recent ejaculation (seminal stains)
6. Electrical stimulation devices (for genital stimulation with low voltage)
7. Plastic bags (used to induce partial anoxia enhancing sensation)