Hospital Sainte Musse, in Toulon, southern France, was evacuated after the unnamed pensioner turned up on Saturday evening hoping that someone would free the explosive from his anus.
Doctors understandably were worried that the shell could explode inside the man, who is understood to have inserted the item in his backside for sexual pleasure.
Bomb squad disposal experts were invited and they determined that there was little risk that the shell would blow up, and managed to put surgeons at ease.
Doctors braced up and made an incision and surgically removed the First World War collector’s item, which measured at 8 inches long (20cm) and more than 2 inches wide (5cm).
A spokesperson for Hospital Sainte Musse said: ‘An emergency occurred from 9pm to 11.30pm on Saturday that required the intervention of bomb disposal personnel, the evacuation of adult and paediatric emergencies as well as the diversion of incoming emergencies.
‘We had to manage the risk in a reactive framework. When in doubt, we took all the precautions.
‘The spokesperson added that the senior citizen was recovering well and was in ‘good health’.