Paul Howes, 48, of Lower Higham Road, failed to stop after the incident and was later found to be in possession of class A drugs.
Howes had been driving along Old Road East, Gravesend, at around 10pm on June 14 last year, when he collided with a parked car.
Seconds later the vehicle mounted the kerb and drove into a teenage girl who was walking along the pathway.
The victim was thrown into a nearby garden and hit a wall, sustaining serious injuries.
Failing to stop, Howes continued to drive along the pavement until his vehicle collided with another car, forcing it into a garden fence.
The collision was witnessed by a number of members of the public who were able to identify the vehicle and Howes as the driver.
During a roadside breath test by attending patrols, Howes was found to be five to six times over the legal limit. He was arrested but later refused to take further tests for driving whilst under the influence of drink or drugs.
While in custody he racially abused an officer and was found to be in possession of cocaine. A subsequent search of his car uncovered 10 further wraps of cocaine and cannabis.
Howes pleaded guilty to causing serious injury by dangerous driving, dangerous driving, failing to stop, racially aggravated public order, failing to comply with an impairment test, failing to provide an evidential sample of blood and possession with intent to supply class A drugs.
He was sentenced to four years and six months’ imprisonment at Woolwich Crown Court on Tuesday. He will also be disqualified from driving for three years upon his release from prison, and will have to take an extended driving retest before he is allowed back on the road.
Investigating officer, PS Chris Wade from the Serious Crash Investigation Unit said: “At the sentencing the judge said this was one of the most serious cases the court had seen for causing serious injury by dangerous driving. Not only did Howes drive on the pavement he failed to stop after he had driven into a pedestrian. It’s lucky the person he hit wasn’t killed and no-one else was injured.”
Read more: All the latest news from Gravesend