Patients were made to wait more than a year for operations after their details were lost due to a computer error.

Barnet and Chase Farm Hospitals Trust, which is now part of Royal Free London NHS Foundation Trust, has been ordered to clear the backlog after it emerged a total of 179 patients were left waiting.

This is despite the national guidelines advising an 18 week waiting time.

The Times Series has been told the backlog was supposed to be cleared six months ago – but is now unlikely to be cleared until next autumn.

As a result, NHS England, which oversees the Barnet Clinical Commissioning Group (CCG), placed a legal direction on it at the end of July and the trust, which has been part of Royal Free London NHS Foundation Trust since July, has now been forced to carry out an independent review as to why this occurred.

It will review its process every four months until the issue has been resolved.

Councillor Barry Rawlings, a Coppets ward councillor and health spokesman for Barnet’s Labour Group, said: “It’s partly down to systems, partly finance because everyone’s trying to save money.

“Each one of those people waiting was in need of treatment, therefore the condition continued longer than it needed to and so people suffered longer than they needed to.

“Conditions don’t tend to get better so while you wait the conditions can often get worse. It will deteriorate the longer you wait. The recovery time is also longer. They have to get a grip, and get a grip soon. We are not getting the health service we deserve in Barnet.”

He also blamed shortage of money due to the Government’s reorganisation of the NHS.

He added: “The government’s system is a bit like the mad hatter’s tea party. It’s worrying.

“It’s unusual because there aren’t many legal directions given out, they’re rare.

“Usually with a problem, part of it is the way data was collected. The data needs to be sorted out, it’s basic bread and butter work. You have to know how long people are waiting. If the simple things go wrong there’s no point doing complicated things.”

Only two other CCGs in the country have legal directions still in place, in Croydon and Thurrock.

Dr Debbie Frost, a GP and chairman of Barnet CCG, said: “Barnet CCG has been working with the Royal Free, which acquired BCFH (Barnet and Chase Farm Hospitals Trust) in July 2014, to tackle waiting times at the hospitals. “NHS England wanted to find a way to work with the CCG to ensure that there is a robust process to get referral-to-treatment times back on track, while continuing to deliver high quality patient care.

“The directions formalise a more proactive, targeted support for Barnet CCG, focused on managing the huge referral-to-treatment times issue only.

“The CCG is working closely with NHS England to address the underlying problems on waiting times for treatment, and ensure that BCFH (as part of the Royal Free) has sustainable plans in place to meet local demands for services in the future.”

A spokesman for NHS England said: “NHS England has already provided practical support, but after carefully considering the ongoing challenges, we have decided to give additional targeted support, that is underpinned by legal directions.

“This is a positive development for the people that the CCG serves - everyone involved in delivering health care in the area is working together to address problems, ensure that standards of care are high, waiting times are reduced, and any disruption to patients is minimised.”