Bosses at a west Hertfordshire hospital have changed their procedures after a patient was fitted with the wrong implant during surgery on their knee.

The patient was admitted to St Albans City Hospital for surgery to replace their right knee joint earlier this year.

The correct knee was operated on, but it was later discovered that the implant they used had been an implant for a left knee.

No corrective surgery has been undertaken, but the patient will be regularly monitored to ensure there are no problems as a result.

As a result of the error bosses at the West Hertfordshire Hospitals Trust – which runs the hospital – say there will now be a ‘stop moment’ during any operation.

And during this pause any implants will be thoroughly checked by both the surgeon and the scrub nurse.

The incident with the wrong knee implant at St Albans City Hospital has been recorded by the NHS as a ‘never event’.

These so-called ‘never events’ are incidents that could have caused serious harm or death to a patient – but which should have been avoidable.

Commenting on the incident, West Hertfordshire Hospitals NHS Trust medical director Mike van der Watt highlighted the change in procedure.

He said: “The ‘never event’ refers to an incident where a patient who required surgery on their right knee, had the correct knee operated on, but had a left knee prosthesis implanted.

“The prostheses for left and right are very similar and therefore, after an assessment involving senior clinicians and in consultation with the patient, it was decided that the prosthesis should remain in situ.

“We have formally apologised to the patient who receives regular check-ups in case of any problems.

“As a result of this ‘never event’ we have changed our procedures to introduce a ‘stop moment’ in theatre during which the surgeon and the scrub nurse thoroughly check the implants when they arrive to ensure they are correct.”

The NHS regularly publish the number of ‘never events’ at trusts across the country.

Provisional data published by the NHS last month highlights 294 serious incidents – between April 2018 and October – that, they say, appear to meet the definition of a ‘never event’.

This is the only ‘never event’ recorded by the West Hertfordshire Hospitals NHS Trust in the latest publication of data.

The West Hertfordshire Hospitals NHS Trust also includes Watford General Hospital and the Hemel Hempstead Hospital. Typically they perform 48,000 planned operations in a year.