The Minister for Health says more scoliosis surgeries have been carried out in Temple Street and Our Lady's children's hospitals already this year than for the whole of last year.
Simon Harris was reacting to ongoing criticism of the amount of children waiting for life-changing surgery.
There are calls for the theater at Our Lady's to operate five days a week.
Minister Harris says a four-month target for surgery will be met but the backlog is making things difficult.
"I have not, in my time as Minister for Health, a greater focus by the Health Service Executive in relation to rectifying this issue," he said.
"We have put in an additional €10m, we have hired additional consultants, we have hired additional theatre nurses.
"More surgeries have been done in Crumlin and Temple Street this year combined than have been done in the entire year last year."