A surgeon in Scotland was allegedly forced to perform a leg amputation with a rusty saw after discovering that no other equipment capable of severing a metal leg plate was available.
A surgeon in Ayr Hospital was cutting though a pensioner's leg and discovered a metal plate.
An orthopaedic surgeon suggested buying equipment to sever the metal plate at B&Q, but the store was closed.
Instead, a saw found in a store room was sterilised and used.
A health board source told the BBC: "An elderly man who was a patient at Crosshouse Hospital needed a leg amputation and was taken to Ayr Hospital for the operation, because that's where the vascular surgeons are based.
"The operating theatre was prepared, he was anaesthetised and the operation began but it was halted after the surgeon had difficulty cutting further.
"That's when he discovered he'd hit a metal plate that they didn't know about. So he frantically sought advice from the consultant orthopaedic surgeon, who suggested going to B&Q."
"However, the store was closed because the operation was being carried out after 21:00, so the surgeon decided to use the saw which was from old hospital stock."
The source added: "The saw was sterilised by soaking in some disinfectant solution and the surgeon proceeded to complete the amputation after cutting through the metal plate.
"If this is a proper investigation it should be shared with all as learning. This should never have happened. I have never come across anything similar in my career."
It is believed that the patient and his family were told about how the operation was conducted some time afterwards.
NHS Ayrshire and Arran told the BBC it was investigating an incident "where standard procedures were not followed".
"The findings of this review and any subsequent recommendations will be shared with clinicians, as well as the family of the patient."