Officers are continuing to investigate the circumstances surrounding a serious collision which took place in Meir Heath last month.
The collision, which occurred on Grindley Lane, at around midnight on 22 May, involved an adapted push bike.
The rider, a 23-year-old man, from the Stoke-on-Trent area, remains in hospital in a serious condition.
A spokesman for Staffordshire and West Midlands Serious Collision Investigation Unit said: “ We are keen to speak with the driver of a white hatchback car which was in the area at the time and may have witnessed the incident.
"We would also like to speak with a male named ‘Richard’ who is believed to have stopped and assisted the casualty at the scene."
Anyone who witnessed the collision and who may have relevant dashcam footage should contact Staffordshire Police on Facebook, Twitter, or call 101, quoting incident number 001 of 22 May.
Alternatively, email the Collision Investigation Unit directly via [email protected] .