David Besley, assistant secretary of the Educational Institute of Scotland (EIS), said teachers are also ending up with post-traumatic stress disorder due to violent incidents.

It comes as three teachers in Aberdeen spoke to the BBC anonymously about their concerns around pupil attacks.

The EIS is calling for the city council to take action.

In November, a report from the union warned pupil violence has increased over the last four years and 82.7% of schools were reporting violent or aggressive incidents each week.

Mr Besley told the BBC’s Good Morning Scotland programme: “We deal with teachers who have been assaulted and go to hospital with broken bones.

“And that’s without, of course, the post traumatic stress disorders and the effects on teachers’ mental health after long-term dealing with very aggressive situations in classes.”