The deal is going to cost North Durham Clinical Commissioning Group £10 for every referral.
The money will go to a company called About Healthcare.
The CCG says it wants to ensure GPs are following clinical guidelines.
The screening will involve patients referred to cardiology, gynaecology, dermatology and gastroenterology out-patients - except for urgent cases.
Local MP Roberta Blackman-Woods is pressing Health Secretary Jeremy Hunt to block the project.
She told the Chronicle newspaper: “It seems clear to me that when a GP refers a patient to a specialist, they are not doing it for the sake of it, but because they believe that person has a health condition which needs further investigation. I don’t think that a private company should have the power to overrule the decisions of the GP.”
Local GP Dr George Rae, British Medical Association regional chair, said there was "a lot of concern" among doctors about the scheme.
He said: “It is not inconceivable that some doctors will feel undermined by this. It adds another layer of bureaucracy, it will add to the workload of already busy GPs and could lead to delays for patients.”
A CCG spokesman promised that the scheme would not delay patient referrals, claiming it was to ensure patients are treated "in the most appropriate way."
Ten patients were treated with the procedure two years ago - and most of them have enjoyed improvements in their knees and quality of life, doctors reported.
The procedure involved taking cartilage cells from the nasal septum, growing it in the laboratory and creating engineered cartilage for the operation.
Details of the apparent success of the phase 1 study were reported in The Lancet today.
The researchers say the patients developed repair tissue similar in composition to native cartilage.
One of the patients suffered further sports injuries and their progress could not be assessed.
The other nine reported "substantial" improvements in the use of their knees and the level of pain without suffering adverse events.
The doctors say they turned to the nose as a source of cartilage because the cells in the nasal septum have a unique capacity to grow and form new cartilage tissue.
Professor Ivan Martin, of the University Hospital Basel, Switzerland, who led the project, said: “Our findings confirm the safety and feasibility of cartilage grafts engineered from nasal cells to repair damaged knee cartilage.
"But use of this procedure in everyday clinical practice is still a long way off as it requires rigorous assessment of efficacy in larger groups of patients and the development of manufacturing strategies to ensure cost effectiveness.
"Moreover, in order to extend the potential use of this technique to older people or those with degenerative cartilage pathologies like osteoarthritis, a lot more fundamental and pre-clinical research work needs to be done.”
Lancet 21 October 2016 [abstract]
The Care Quality Commission has taken the step after overspending its budgets for practice inspections in a desperate bid to meet targets.
The practice fees are due to be reimbursed by NHS England, allowing the commission to boost its budgets from NHS funds.
Under the proposals a practice with fewer than 5,000 patients will see fees increase from £2,187 to £3,845. The largest practices with more than 15,000 will see fees increase from £3,365 to £5,918.
Dr Mark Sanford-Wood, from the British Medical Association's GP committee, condemned the increases as "scandalous."
He said: "While NHS England has promised to reimburse GP practices for the increase in fees, it nevertheless will divert overstretched NHS funds from other budgets from frontline patient services to maintain a system of regulation and inspection in which the majority of GPs have little confidence.
"A recent BMA survey found that nine out of ten GPs felt the current inspection scheme was flawed and bureaucratic, with the vast majority reporting that it diverts GPs, nurses and other staff away from treating patients.
“The CQC is planning to significantly reduce the scale of its GP inspections which should lower the cost of regulation. This makes the proposal to increase its fees inexplicable and wholly unjustified."
CQC chief executive David Behan said: “The fees paid by providers enable us to fulfil our purpose of making sure health and social care services provide people with safe, effective, compassionate, high-quality care."
The research in Berlin is being backed by Back to the Future star Michael J Fox, who suffers from the disease.
The scientists say they have developed a "flux compensator" that uses magnetised xenon gas to enhance MRI scanning.
It aims to detect alpha-synuclein proteins, thought to herald the onset of the disease.
In the movies, the time travelling car is powered by a flux compensator, which adjusts the time line.
The new German technique adjusts the results of MRI scanning and working with infrared light enhances the magnetisation of xenon.
The scientists say it will allow for the detection of previously "inaccessibly" small amounts of a substance.
They say the technique is equivalent to enhancing the magnetic field of the scanner by 20,000 times.
The project, led by Dr Leif Schröder at the Leibniz-Institut für Molekulare Pharmakologie, is receiving nearly 350,000 dollars from the Michael J Fox Foundation over three years.
A spokesman for the Institut said: "In the tradition of Campus Buch, the latest methods in physics in the life sciences will be used to bridge the gap between the legendary flux compensator and potential applications supported by The Foundation."