The NHS says it has secured a rescue package of alternative medical cement to allow joint surgery to continue. Last week hospitals had been told to postpone treatments, including knee and hip replacements, after the health service's main supplier encountered a major production problem. The NHS was thought to have only two weeks' supply in stock and so was focussing on emergency patients and the most complex cases on the waiting list. But NHS England believes the shortfall will now be covered after a new supplier was found and an existing supplier agreed to up its deliveries.…