Why do injuries sometimes cause itchiness?

I fell and hit my butt on some ice a few weeks ago. The first few days I was sore, but within the last week there’s been no soreness but some itchiness.

I’m not asking for medical advice. It’s not severe, and I don’t need a doctor. I’m asking out of curiosity.

Did you scab? It is my personal speculation that scabs are rough and poke into tender, newly forming skin causing itching. if you have scabs, soften them with antibiotic cream.

Injured cells release histamine, so you itch.