Rosy, a letterbox and a handsome fireman

I hadn't seen my friend Rosey for a couple of months,  then I bumped into her in town the other day. Literally! Well, almost; actually she bumped into me. She was walking with a limp and I asked her why. She said she'd hurt her wrist (I know what you are thinking - don't ask, I didn't!) She showed me a nasty scar.

It seems that she posted a letter the other day, then realised she'd left the stamp off the envelope, and so she pushed her hand through the slot to try and retrieve it. Not only did she fail in her attempt, but her hand refused to exit the orifice and stuck tight. Needless to say, her predicament attracted a few curious glances from passers-by, one of whom offered to call the post office for assistance. A postman duly turned up and after opening the flap or door whatever it's called, attempted to break Rosey free to no avail. He was a bit grumpy so Rosey put on her best dampened-spirits look hoping to gain a bit more sympathy. At that moment, a passing police car screeched to a halt and PC Plod came across to see what was going on. He warned her that she could be 'arrested for attempted theft from a Royal Mail postbox'. Rosey adopted her well practiced plaintive pout and forced a small tear down her cheek. It worked and he let her off with a caution. Moments later a fire engine arrived. Suddenly her predicament turned from difficult to interesting as a handsome fireman had a go at freeing her hand by grasping twisting and shoving it - or softly caressing it in Rosey’s version of events! Guess what happened next. Yes, an ambulance appeared. To cut what is becoming a long story short, between all three emergency services they eventually managed to cut her free, destroying the letter box in the process. 

By the way, they found her letter. She had in fact attached a stamp all alon