BRUTAL ATTACK: Teen sentenced to 10 years prison after rape

A YOUTH will remain in prison until at least 2024 over a violent break-in and sexual assault.

The boy, who cannot be named, appeared in the dock of Lismore District Court on Tuesday.

He had last year pleaded guilty to the charges of wounding a person with intent to cause grievous bodily harm, aggravated sexual assault and committing an aggravated serious indictable offence in a dwelling involving the deprivation of liberty.

He was arrested on December 20, 2017, four days after he broke into a Lismore home.

His victim, a woman who was alone in the home at the time, woke to find him standing over her bed with a knife in his hand.

She tried to negotiate with him before he sexually assaulted her and further attacked her, including with the knife.

His assault with the knife was so brutal, the tip of the weapon broke off inside one of his victim's wounds.

DNA evidence tied the teen unequivocally to the crime, the court heard.

He was almost 17 years old at the time of the offence.

Judge Wells said the victim had suffered lasting physical and psychological wounds from the attack.

"She was traumatised, of course, very deeply, not just by the offence itself but what followed," Judge Wells said.

"Not only has she suffered physically and emotionally in a most serious way... she felt she could no longer safely live in the house that she lived in."

The teen was on probation at the time of the attack and had committed five prior offences of break-ins involving theft, along with assault, affray and property-related offences.

The court heard his upbringing was marred by serious "social disadvantage" and he had been "exposed to various forms of trauma".

His mother had suffered from alcoholism and his father had been imprisoned for much of the defendant's childhood, the court heard.

Judge Wells sentenced the youth to a term of 10 years' prison, with a non-parole period of six and a half years which will expire on June 19, 2024.

The sentence was backdated to the date of his arrest.

Judge Wells ruled that he would spend part of that sentence in juvenile detention, until he is 21 years of age.