Congratulations – Kindertrauma is an AWESOME site! Here's my half-remembered trauma:
Sometime in the late '80s/early '90s I saw a scene on UK television; (I think) a man was on a bed, possibly a four-poster, and somehow bars appeared from the sides of the bed turning it into a big cage. I think the bars shot up from the edges of the bed, but I'm not sure.
A very hazy memory, but it scared the crap out of me at the time. If anyone can name this film or T.V. show that would be amazing.