A frenzied loner tried to choke his frail mother with her own Zimmer frame after setting fire to her garden shed.
Andrew Brooks staged the horrific attack on 62-year-old Patricia Brooks as she slept at her home in Corby in July last year.
London’s Court of Appeal heard Brooks, 35, of Stevenage, Herts, also dragged his mother round by the neck, flung her to the ground by her hair and doused her in white spirit.
He then pinned her to the floor with her Zimmer frame and tied a shirt around her neck to try to strangle her.
Brooks was locked up indefinitely for public protection at Northampton Crown Court in January last year after admitting false imprisonment, assault causing actual bodily harm and arson.
He will not be freed until the Parole Board is convinced he is no danger to society.
He was ordered to serve at least 32 months – but that was cut to two years by three top judges.
Lord Justice Rix heard Mrs Brooks was already so troubled by her son’s behaviour she had taken to sleeping in her chair at night, although she was in bed when Brooks struck.
Brooks put a fire poker to his mother’s face and dragged her by the neck around her home, telling her it was “his house and that she would never get it”.
Lord Justice Rix said that when she screamed, he clamped his hand over her mouth, grabbed her by the hair and flung her to the ground, before “pinning her to the floor with her Zimmer frame”.
The judge added: “He put a shirt around her neck in the form of a ligature in an apparent attempt to strangle her.”
Mrs Brooks managed to flee from her house to seek the help of neighbours.
But her son appeared in her neighbours’ hallway, dragging her back to her home where he trampled on her and doused her in white spirit.
The court heard that when police arrived, they saw Brooks trying to set fire to a blanket, with the garden shed already burned. He confronted officers brandishing a hammer and was restrained with CS spray.
Mrs Brooks was left profoundly traumatised by the attack, and has since moved.
The case reached the Appeal Court as Brooks challenged the open-ended sentence, which is reserved for the most dangerous offenders.
Lord Justice Rix said Brooks, who has a history of mental health problems, was guilty of a “most awful attack”.