Prison officers were injured 137 times last year while trying to restrain an inmate.
That's up from 91 similar incidents in 2017, according to the Irish Examiner.
"Restraint intervention" cover situations where a prisoner is not complying - including when they're assaulting another inmate - and prison officers are injured trying to restrain them.
Of the 137 such incidents last year, 11 were recorded in Castlerea Prison.
These are in addition to 110 direct assaults on staff by prisoners last year.
The annual figures have been rising steadily since 2015.
Mountjoy and Cork prisons had the highest number of assaults on staff by prisoners.