Prison officer rushed to hospital after inmate cuts his throat at HMP Nottingham
Over the same period, there had been 198 incidents where prisoners had climbed onto safety netting between landings.
HM Inspectorate of Prisons said: "This level of disorder contributed to a tense atmosphere at the prison," adding that many violent incidents, including serious ones, were not investigated at all.
Chief inspector of prisons Peter Clarke Clarke said the prison needed to do "much more" to tackle the problem of drugs which was "inextricably linked" to violence in his report.
HMP Nottingham is a category B male prison which expanded in 2010 to hold 1,060 prisoners.