The study focused in on figures from Belfast, which currently sits at an average of 36 weeks, a rise of almost 100% in two years.
It’s not clear how many people have to wait for that inflated timeframe, but the report claims it’s clear that the department in that region is not meeting its targets.
The NHS have previously said that it is a legal right for people to wait no longer than 18 weeks.
The focus of this investigation is on the Belfast clinics, but conditions aren’t much better in the rest of the UK, especially England.
Surgeons have already revealed their displeasure at waiting times, because they feel their area of expertise is being unfairly targeted for budget cuts. They added that, in the long term, knee and hip replacements save society money.
A spokesperson for the Department of Health said, "Long waiting times for appointments are unacceptable and that's why the minister (Edwin Poots) has set targets that people should be seen within acceptable time scales.”
They added that £10m has been put aside to try and improve the picture nationwide, targeting “specialities which are particularly at risk of falling short of the 2012/13 outpatient and inpatient waiting times targets - which include orthopaedics."