Doctors including a former medical director have written to Scottish Health Secretary Shona Robison demanding a judicial review of the way medical staff are being treated by a major health board.

More than 20 consultants have signed the letter sparked by the suspension of two surgeons from NHS Grampian - the Queen's Surgeon in Scotland Professor Zygmunt Krukowski and his colleague, Dr Wendy Craig.

Both clinicians are said to have raised concerns about issues affecting Aberdeen Royal Infirmary and the letter to Ms Robison says: " In recent years there has been a series of suspensions of senior consultants at Aberdeen Royal Infirmary. In each case that we're aware of, the doctor involved had raised concerns about some aspect of management or of patient safety. Consistently, these 'whistleblowers' have been isolated, dislocated from their work to the detriment of patients, subjected to damaging psychological pressure and finally referred to the GMC and suspended from duty."

Last year an NHS Grampian consultant raised concerns with then Health Secretary Alex Neil about serious problems at Aberdeen Royal Infirmary. An independent investigation by Healthcare Improvement Scotland (HIS) followed and there were a number of staff changes at senior level. HIS ultimately published a damning report which highlighted serious shortages of doctors and nurses, a forceful style of management which some described as "bullying" and remote managers who did not appear to be taking meaningful decisions.

The letter to Ms Robison expresses support for the new chief executive and chairman, but also concern that the recent suspensions of Professor Krukowski and Dr Craig indicate that the way those who speak out in the health board are treated has not changed.

It continues: "Both of these surgeons are widely recognised for the excellence of their work, their contribution to medical knowledge and their commitment to their patients and to the NHS."

A range of doctors who worked for the health board in the past but have since moved on or retired have signed the letter including Dr Donnie Ross, who was medical director of Aberdeen Royal Infirmary between 1996 and 2003. They express concern that recruiting and retaining staff has "become next to impossible" as a result of "the toxic environment" in the hospital which they were once so proud to be part of.

The consultants are calling for Professor Krukowski and Dr Craig to be reinstated and " for an urgent and wide-ranging judicial review of medical management in NHS Grampian, focussing particularly on the use of suspensions and other disciplinary measures taken against medical staff in the last few years."

In a statement, the health board said: "We cannot - and will not - discuss matters involving individual members of staff.

"NHS Grampian has been subject to reviews by Healthcare Improvement Scotland (HIS) and the Royal College of Surgeons of England (RCSE). These reports found issues with leadership and management, culture and behaviour, accountability and governance within NHS Grampian. We accepted all of the recommendations made at the time.

"We acknowledge this has been a challenging time for NHS Grampian. We firmly believe we are making good progress in addressing the issues raised.

"The HIS review did not raise any consistent or widespread concerns about patient safety or about the quality of care across NHS Grampian.

"We continue to fully support staff who raise patient safety concerns and investigate each case thoroughly."