Keith Bruce, 18, who had been bailed by magistrates on charges involving three stolen cars, led Constable Ken Moss on a terrifying 19-mile journey.
Two girls, on the run from a children's home, were in the stolen Vauxhall Astra driven by Bruce. Both were injured in the crash, one losing an arm.
Sentencing Bruce to two years in a young offenders' institution, the maximum possible, Judge David Savill said: 'As a result of your arrogance and selfishness two people have suffered appalling injuries. You blighted their lives and you will have to live with that. This punishment must not only punish, but deter others. I cannot recall a worse case of dangerous driving than this.'
He also banned Bruce, of Buller Street, Selby, North Yorkshire, from driving for five years.
Bruce was on bail for driving two stolen cars and being carried in a third stolen car before he got behind the wheel of the Astra, stolen in York last November.
Accompanied by the girls, aged 15 and 16, he drove to Scarborough, but PC Moss spotted the car as they headed back to York. Andrew Kershaw, for the prosecution, said speeds reached 120mph. PC Moss was not chasing but following 'at a safe distance'.
Near Malton, North Yorkshire, Bruce took a bend at high speed and smashed into a lorry and trailer, which went out of contol and blocked the road.
PC Moss's car hit the trailer at 57mph, did a 180-degree turn in mid-air and landed facing the other way. He suffered many injuries to his face and body and is still trying to walk again.
The 16-year-old girl, who has been cautioned, was flung from the wreckage and lost an arm. The 15-year-old, who broke her collarbone, was sentenced to 18 months' supervision.
Bruce, a machine operator, admitted aggravated vehicle-taking, dangerous driving, driving stolen vehicles and having no insurance.
Afterwards PC Moss, 35, said: 'I bear no grudges against the boy but I just hope he realises the enormity of what he has done.'
Legal history was made yesterday with the first prosecution of a speeding driver based on evidence from speed-trap cameras. Stephen Quashie, 19, a postman from Harlesden, north-west London, was fined pounds 156 plus pounds 25 costs after pleading guilty to driving at 78mph on the A40, Western Avenue, which has a 50mph limit. He also received six penalty points.Reuse content