Internal decapitation, atlanto-occipital dislocation, or orthopedic decapitation describes the rare medical condition in which the skull separates from the spinal column during severe head injury. This is usually fatal, since it generally involves nerve damage or severing the spinal cord.
The practice of hanging relies on internal decapitation, as it creates a situation where subjects' necks are broken under their own weight. A botched hanging can result in an external decapitation or, if the neck does not break, a situation in which the subject strangles to death.
People who have survived internal decapitation
- In January 1998 Sandra van Dommelen, a 21-year-old woman from Tilburg, the Netherlands, suffered an internal decapitation after a moped crash. Prompt medical attention including external fixation using a halo device allowed for an almost complete recovery. 
- In April 2004, a 14-year-old Phoenix, Arizona, boy suffered internal decapitation after being struck by a car while on his bike. The boy recovered from his injuries, and was featured on the shows I Came Away Alive for the National Geographic Channel, as well as Untold Stories of the E.R. and Medical Incredible for the Discovery Health Channel.
- In September 2006 Chris Stewart, 12, survived an internal decapitation in a racing crash in Alton, Hampshire, UK.
- In April 2007 Andrew Love survived internal decapitation after a motorbike accident in Telford, Shropshire UK
- In January 2007, a Lincoln, Nebraska woman survived, as there was little nervous system damage involved.
- In April 2007, Dean Laurent of Central Illinois survived an internal decapitation with addition c1-3 fractures . Dean spent 5 weeks in ICU and after 15 months of rehab has made an almost complete recovery . With memory issues and 12th nerve Palsy being the only lasting effects
- In July 2007, an 11-year-old boy, Ryan Ooms, in Saskatoon, Saskatchewan, also survived with a hospital stay of only two and a half weeks.
- In October 2008, a 9-year-old Hillsboro, Texas, boy was internally decapitated in a car accident. Despite being given little chance for survival, he made an almost full recovery within 3 months of the incident and was able to return to school in the beginning of 2009.
- Jon Wilhite, a former baseball player and California State University, Fullerton, catcher, suffered the same injury in a vehicular collision on April 9, 2009.
- In August 2009, 18-year-old Amanda Kapp suffered internal decapitation, as well as numerous other injuries resulting from a serious car accident[where?].
- On Christmas Eve, 2009, 6-year-old Meadow Rhynes from Providence Village, Texas, suffered an internal decapitation from a head-on car accident. Rhynes also had traumatic brain injury, brain stem damage, and massive internal injuries. Neurosurgeons at Children's Medical Center (Dallas) performed an occipital-cervical fusion from the C0-C5 to fix the injury of the head coming off of the spine. Rhynes' other injuries were also taken care of and Rhynes was back to almost 100% baseline only a year after the accident occurred.
- On December 19, 2010, a 20-year-old woman, Amber McKinney, was in an accident[where?] with her boyfriend and survived the internal decapitation. Along with internal decapitation, she sustained a brain injury and a broken femur. She recovered in two months.
- On July 31, 2011, United States Marine Corps Gunnery Sergeant David Smith was rear-ended by a drunk driver while sitting on his Harley Davidson motorcycle at a stop light in Rancho Bernardo, San Diego, California. Smith went on to survive the injury, having the C2, C3 and C4 cervical vertebrae fused by surgery through the back of his neck, and then all three fused to the base of his skull with titanium hardware nine days later. Smith was walking two days after surgery and in physical therapy within two weeks and was released from hospital on August 23, 2011. Smith returned to full duty with the USMC and retired on June 11 of 2014. 
- In September 2011, then-22-year-old Rachel Bailey was in a car accident in Phoenix, Arizona. Bailey was rescued by firefighters and spent a month in John C. Lincoln Hospital's Intensive Care Unit. She is now able to walk and talk again, but does not remember the two days prior to the accident or the month and a half following the crash.
- In the fall of 2012, Kimberly Flanigan, from Cincinnati Ohio, was a passenger in a vehicle that slid on black ice causing a violent crash. Upon arrival at the hospital, surgeons indicated she had suffered an internal decapitation. Doctors were able to not only reattach her head, but also stabilized her spine and prevented further damage and paralysis.
- At 3:00 AM, October 26, 2014, John Boyer of Centennial, Colorado, was ejected 200 feet from a vehicle in a car accident caused from the vehicle driver falling asleep at highway speed. Mr. Boyer also broke his collarbone and lacerated his spleen. His spleen was removed and his collarbone repaired in addition to the fusing of his skull, C1, and C2. Mr. Boyer was released from the hospital on November 7, 2014, 12 days after the accident. He continues his recovery from the accident at home, showing zero neurological deficits to date.
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- CBS 11 Medical News
- Giasone, Barbara (2009-07-09). "How doctors saved Adenhart crash survivor's life". The Orange County Register. Retrieved 2009-08-28.
- Delesline III, Nate (2010-01-25). "Lucky to be alive". Culpeper Star-Exponent. Retrieved 2010-05-23.
- Meet Meadow R., Providence Village, TX
- Janet St. James (2011-01-21). "Young woman's recovery after traumatic brain injury". WFFA Dallas/Fort Worth. Retrieved 2011-08-23.
- Marine recovers, forgives driver
- "Crash survivor with internal decapitation thanks Phoenix firefighters". Retrieved 2012-09-25.
- I am Mr. Boyer's step-father