Life-changing open-heart surgery begins from the moment the chest is opened and the heart is stopped, right through as a new aortic valve is implanted, and the heart is restarted.
In a time-critical procedure, the ends of the bones of a patient's degenerated knee joint are removed and replaced with specially designed metal-and-plastic substitutes.
With millimetre precision, a cancerous section of bowel is pulled out of the body while still attached internally, so that the tumour can be cut out before the rest of the organ is re-inserted.
