The collision happened after the man came out of his house to challenge burglars who had broken into his neighbour’s house on Narrowboat Close, Exhall.
Two people, believed to be the burglars, left the scene in a car which collided with the man.
The man was rushed to hospital where he underwent surgery.
The vehicle was initially described as a blue Vauxhall hatchback. Officers now believe it was a hatchback Vauxhall Corsa with a 67 number plate.
Officers investigating the collision at 10.23am yesterday (Tuesday 17 April) are appealing for witnesses.
Police Staff Investigator Len Bell said: “The actions of the driver, whether they were deliberate or accidental, have put a man in hospital.
“We need to speak to anyone who witnessed the incident or can help us to find the car or its occupants.”
Anyone with information should contact police on 101 quoting incident 111 of 17 April 2018 or the independent charity Crimestoppers, anonymously, on 0800 555 111 or via www.crimestoppers-uk.org