Neck holds, armlocks and reflex cardiac arrest
- Finding
A neck hold can cause unconsciousness within seconds and kill, sometimes without marks: the scene, witnesses and the neck dissection decide.
What it is
Neck holds compress the neck with the arm or forearm, usually from behind. There are two types: one presses on the front of the neck and compresses the larynx and trachea, and the vascular restraint compresses the sides of the neck and the carotid vessels. They are used in fights, combat sports and when police or security staff restrain people. Loss of consciousness usually comes within about 6 to 14 seconds. Pressure on the carotid sinus can lower the heart rate and blood pressure through a vagal reflex, but it is rarely the main mechanism, and reflex cardiac arrest is a diagnosis of exclusion. A death during restraint demands an independent investigation.
How to tell it apart
- Versus manual strangulation: that leaves round fingertip bruises and nail abrasions; a forearm hold leaves more diffuse marks or none.
- Versus positional or chest-compression asphyxia: in face-down restraint on the ground both may combine.
- Versus sudden natural death: the scene, witnesses, video and the neck injuries separate them.
- Stimulant intoxication and intense exertion during restraint raise the risk of death.
How to recognise it
- Linear or diffuse bruises and abrasions on the front or sides of the neck from the forearm.
- Petechiae of the face and conjunctivae, especially if compression was prolonged.
- At autopsy: haemorrhages in the neck muscles and sometimes fractures of the hyoid or the thyroid cartilage.
- Restraint injuries elsewhere: wrists, arms, back and signs of pressure on the chest.
How it forms
- Compressing the jugular veins hinders blood leaving the brain, and compressing the carotids reduces blood reaching it.
- The airway resists compression better than the vessels, which is why the main mechanism is usually vascular.
- Stimulating the carotid sinus can cause bradycardia and hypotension through the vagus nerve.
Two types of neck hold
| Feature | Across the airway | Vascular restraint |
|---|---|---|
| Area compressed | Front of the neck: larynx and trachea | Sides of the neck: carotids and jugulars |
| Main mechanism | Airway obstruction and vascular compression | Reduced blood flow to the brain |
| Possible internal injuries | Fractures of the hyoid or thyroid, laryngeal haemorrhage | Neck muscle haemorrhages, carotid dissection |
Next step: what to do and document
- In a survivor, ask about loss of consciousness, hoarseness, pain on swallowing and neurological symptoms, and consider imaging of the neck vessels.
- Describe and photograph the neck injuries and restraint injuries all over the body, even if minimal.
- At autopsy, dissect the neck layer by layer in a bloodless field and record each layer.
- In a death during restraint or in custody, request video, records and witness statements, and follow the independent investigation standards of the Minnesota Protocol.
- Request full toxicology: stimulant intoxication and alcohol are common in these deaths.
Common mistakes
- Ruling out a neck hold because there are no external marks.
- Dissecting the neck without first creating a bloodless field (removing the brain and chest organs first): artificial haemorrhages are created.
- Attributing death to reflex cardiac arrest without ruling out other causes.
- Not seeking video, witnesses and records of the restraint.
Test yourself
Think of the answer, then tap the question to see it.
How long does a well-applied vascular neck restraint take to cause loss of consciousness?
About 6 to 14 seconds, according to studies in volunteers and in combatants.
What is the difference between a hold across the airway and a vascular restraint?
The first compresses the front of the neck (larynx and trachea); the second compresses the sides of the neck and the carotid vessels.
Why is reflex cardiac arrest a diagnosis of exclusion?
Because the carotid sinus vagal reflex exists but rarely explains death on its own and leaves no findings of its own.
Why are the brain and chest organs removed before the neck is dissected?
To leave a bloodless field and avoid artificial haemorrhages that can be mistaken for injuries.
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Educational content on forensic and legal medicine; not legal advice and no substitute for the technical guides of Colombia's National Institute of Legal Medicine and Forensic Sciences. Laws change: each page links the official text and says when it was last checked. For a real case, follow the guide in force and ask the competent authority.
Sources: Approach considerations for the management of strangulation in the emergency department (Journal of the American College of Emergency Physicians Open, PubMed Central, 2022); Carotid Artery Occlusion Caused by the Judo Chokehold Technique, 'Shime-waza' (Internal Medicine, PubMed Central, 2017); The Minnesota Protocol on the Investigation of Potentially Unlawful Death (2016) (Office of the United Nations High Commissioner for Human Rights, 2017).
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