One possible cause is https://en.wikipedia.org/wiki/Body_integrity_dysphoria https://en.wikipedia.org/wiki/Body_integrity_dysphoria but there are related condit

One possible cause is https://en.wikipedia.org/wiki/Body_integrity_dysphoria https://en.wikipedia.org/wiki/Body_integrity_dysphoria but there are related conditions with other names. I saw an interview years ago on TV and someone was saying it felt like that appendage was not part of their body, it belonged to someone else. It was so mentally uncomfortable they'd rather remove it.