A young man facing charges over crashing into two police officers and injuring one so badly he lost his foot in Sydney's southwest earlier this year has been granted bail.

Jakob Thornton was charged with two counts of dangerous driving occasioning grievous bodily harm after crashing into senior constables Jonathan Wright and Matthew Foley as they set up a random breath testing station in Leumeah in February.

He was allegedly texting and driving when he crashed.

Jakob Thornton has been granted bail after he severed a policeman's foot during a car accident in Sydney's southwest. (Supplied) (Supplied)

The 22-year-old alleged repeat offender, who likely suffers PTSD, was granted bail in the NSW Supreme Court today when he appeared via video link from prison.

The senior constables were pinned between the car and a police van and surgeons were forced to amputate Sen Const Wright's right foot, and Sen Const Foley suffered a fractured leg.

Mr Thornton's mother, Katja, who will pay up a $5000 surety as part of bail conditions, began to cry in court as Justice Peter Hamill delivered his ruling.

Jakob's mother Katya Thornton wept in court as the judge made his ruling. (AAP) (AAP)

Thornton, who the court heard is displaying symptoms of post-traumatic stress disorder, sighed and appeared exasperated as a man could be heard screaming and hooting repeatedly in the background from his prison room throughout the hearing.

"That sounds like a nice place for a young man to be," Justice Hamill said.

He said while Thornton has a "cascading" series of other driving offences, he has very little criminal history.

Officer Jonathan Wright was forced to have a 15cm amputation of his right foot. (Supplied) (GoFundMe)

Although Thornton's serious charges normally result in a custodial sentence if convicted, Justice Hamill noted a lengthy period was expected before he even received a committal hearing.

Justice Hamill dismissed prosecution claims that Thornton may fail to appear when his matter is next heard in Campbelltown Local Court next month or pose a danger to the community, because as he stated Thornton doesn't own a car or a passport.

Thornton was allegedly looking at his phone for 10 to 20 seconds when he smashed into the two officers.

The crash took place in Leumeah, in Sydney's southeast, in February. (9news)

Court documents show Thornton couldn't remember whether he applied the brakes when he hit the officers at 60km/h on Campbelltown Road at about 8.20pm on Friday, February 16.

His provisional licence has been suspended four times and he was caught using a mobile phone while driving two years ago.

Justice Hamil ordered Thornton to reside at a home in Bankstown and report to the local police weekly, not to drive and to be of good behaviour.