A senior executive at a Lincolnshire NHS trust has been suspended after health bosses said hundreds of patients had waited too long for treatment. A review by the NHS East Midlands focused on patients at Lincoln County Hospital's orthopaedic unit.
Helen Scott-South, interim chief executive of the United Lincolnshire Hospitals NHS Trust, has been suspended "as a neutral action", the trust said.
NHS East Midlands said it was taking the matter "extremely seriously".
Patients are now being contacted so they can be treated as quickly as possible. David Bowles, chairman of the United Lincolnshire Hospitals NHS Trust, said he would like to apologise to patients who have had to wait longer the maximum wait time of six months for operations.
He said that the problem only affected elective surgery, which is a planned operation, such as hip or knee replacements and other orthapedic procedures.
"It seems around 300 patients have waited longer than they should have done but it's evident that a fair proportion of those people have now already been treated.
"The root of the problem comes back to how you actually calculate waiting times. Rules are quite complicated and simply have not been applied properly in the trust for quite some time," he said.
Dr Barbara Hakin, chief executive of the NHS East Midlands, said she was aware of approximately 100 further patients who have already waited close to the maximum waiting time and who do not yet have an agreed treatment date.
Senior manager Avril Johns will oversee the day-to-day running of the trust while a further investigation takes place.
A hotline has been set up for patients who have been waiting for an operation for more than six months.