O'Connor told ABCNews.com he experienced a similar childhood full of confusing thoughts. He used to hold his legs still on long car rides with his parents and imagine he was paralyzed even though he didn't fully understand what that meant at the time. As an adult, he, too, tried to injure himself to become paralyzed, but he was not successful and said he has no intentions of trying again.
O'Connor remembers the relief of finding other people like him in the 1990s and said he gets at least six letters a month from transabled.org visitors who want to thank him for making them realize they're not alone, either.
Currently, transabled.org has 35 authors, five of whom write regularly, O'Connor said. Ahiruzone.com has 121 members, Comer said, adding that it's not clear how many of them actually have BIID.
Dr. Michael First, the research psychiatrist at Columbia University in New York who coined the name BIID, said he estimates that there are thousands of people in the United States suffering quietly with it. Of his two current patients in New York City, one uses a wheelchair fulltime and the other uses it at home in secret. Neither physically lacks the use of their legs.
First has studied 52 patients who want to be amputees and another 53 who wanted another disability, which isn't limited to spinal injuries. Some BIID patients long for blindness and deafness, he said.
"The phenomenon starts in childhood in almost all cases," he said. "They go through life feeling chronically uncomfortable, miserable. The way that they should be is not the way that they actually are."
Enter the Media
In 2007, Jerry Springer introduced the world to Sandra, a transexual who chopped her legs off with a power saw because "my brain told me to." Springer called it "the most bizarre show" he'd done in his 15-year history. At the time, BIID wasn't on Springer's – or Sandra's – radar, but she laughed it off and returned for a show that included a pre-taped re-enactment of how she cut her own legs off with a saw.
Between 2004 and 2010, BIID appeared in two documentaries and one feature film at Sundance Film Festival. ABC News did a story on it in 2006, but all interviewees hid their identities.
Chloe Jennings-White decided she had nothing to hide and became something of a spokesperson for BIID a few years ago because she realized that everyone she cared about already knew that she wanted to be a paraplegic so badly that she'd tried hurting herself.
"I looked at my own situation and realized I did not have any of the reasons [to hide] that anybody else had," Jennings-White said. "What's my excuse?"
Jennings-White uses a wheelchair to treat her BIID, and although she was skeptical that it would help her at first, she calls the feeling of first sitting down in the chair "magical." She now lives most of her life in a wheelchair, but uses her legs to hike, drive and occasionally ski -- which she hopes will finally paralyze her.
"I knew it was weird to want to not have the use of one's legs," she said, remembering her years of secrecy, including how she kept an intentional bike accident from her mother when she was 9 years old. "I just didn't think anybody else could understand what that was like so I kept it to myself."
Jennings-White is also intersex, a condition in which someone has ambiguous genitalia. She was born as Clive before she changed her name to Chloe.