A woman was run over after she collapsed into Wye Cliff Road, Handsworth on Monday 9 March after 10.30pm.
She was left seriously hurt after she was struck by a hit-and-run driver.
It is believed the 35-year -old suffered serious spinal injuries when she was hit while lying in the road.
Police say the driver failed to stop at the scene and officers are now urging any witnesses to come forward.
Detectives are speaking with witnesses and trawling CCTV to establish the circumstances of the collision but believe the vehicle involved was a small dark-coloured hatchback.
Det Ch Insp John Askew from force CID, said: “At this stage we are working to establish what exactly has happened here.
“A woman has been left with potentially life-changing injuries and we would urge anyone who may know who the driver of the car was, or may have any dashcam footage, to contact us.”
If you have any information contact us, quoting log 3787, via Live Chat at west-midlands.police.uk between 8am and midnight, call 101 anytime or contact Crimestoppers anonymously on 0800 555 111.