NHS Grampian accounted for nearly 4,000 of the 14,000 fewer operations NHS Scotland carried out this year.
The North-east board cut the number of planned procedures, like hip and knee replacements, from 22,566 last year to 18,825 in 2017.
By contrast, NHS Highland saw just 72 fewer procedures, with NHS Orkney and NHS Western Isles carrying out, respectively, 90 and 88 fewer – and numbers in NHS Shetland rose by 118 to 1,257.
For NHS Scotland as a whole the figure fell from 210,517 to 196,427.
An NHS Grampian spokeswoman said the decrease was “a direct result of the challenges we have faced in staffing”.
She added: “This does not just cover theatres themselves but vital pre- and post-operative care.
“We continue to actively recruit to a range of posts but – in common with many Scottish boards – we are facing a shortage of suitably qualified candidates in some areas.
“While we are unable to see all elective surgical patients within the 12 weeks timescale set out by the Scottish Government, our first priority is to ensure the most urgent patients get treated promptly.”