A TEEN mum who hacked a man with a meat cleaver during a horrifying eight-hour hostage ordeal will spend two years in youth detention.

She was two days short of her 18th birthday when she abducted the man, tied him up and tortured him during a gruelling "interrogation".

Police allege the girl's mother and at least three others were involved in the attack on the man, 34, who spent more than three weeks in hospital and was left with permanent brain injuries.

The teen wiped away tears as full details of the "shocking and shameful" crime were heard during sentencing at a Children's Court.

In a victim impact statement the man's mother said she didn't recognise her son when his body was dumped on her doorstep following the assault early last year.

"They not only kicked his head in, they stabbed him all over his body, slashed his face all over, tied him up and literally tortured him. They almost killed him,'' she said.

The court heard the victim was subjected to hours of physical and psychological torment during the brutal drug-fuelled attack.

"You kept at the attack despite him being already injured and not able to escape,'' the magistrate said.

"It's very hard to imagine the terror and suffering he felt during his imprisonment,'' she said.

The court heard the teen and her mum took the law into their own hands after suspecting the victim, an associate of theirs, of robbing their house.

Despite protesting his innocence, the man had the word "DOG" carved into his forehead before he was kicked in the face and spat on.

The teen used a meatcleaver to hack at the man's legs while questioning him about why he committed the burglary.

It later emerged the teen's boyfriend was behind the burglary.

The man spent more than a week in an induced coma after emergency brain surgery. The court heard the victim had acquired a brain injury and would require medical treatment for life.

Police failed in a bid to have the girl sentenced as an adult arguing the seriousness of the crime, and her age, made it inappropriate for the matter to be heard in the Children's Court.

The teen, now a 19-year-old mother, pleaded guilty to charges including intentionally causing serious injury and false imprisonment.

The court heard she suffered a deprived upbringing within a dysfunctional family and that her moral culpability was reduced because of her drug use.

Four other people are facing charges over the incident.

shannon.deery@news.com.au