Shane Allen Wheldon pleaded guilty to 12 charges, including causing grievous bodily harm and multiple counts of aggravated assault, aggravated burglary, unlawfully injure property and stealing.

In April 2018, Wheldon went on a violent crime spree after a failed attempt to get money from Centrelink.

He tried to burgle an Invermay house being used for short-term accommodation, but only managed to steal a greeting card before setting off the alarm and fleeing.

The 40-year-old then damaged the fence of another house in the same suburb with a hammer, before making his way to Beryl Rae Dix's house.

The thief asked Dixon Kenneth Gray, who was painting the outside of Ms Dix's house, if he could jump the fence, but Mr Gray said no.

Wheldon hit the painter in the head with the hammer a number of times, knocking him unconscious.

Mr Gray said the next thing he remembered was Wheldon patting down his overalls while he was lying on the floor.

Wheldon then went inside Ms Dix's house, knocked her unconscious by hitting her with his forearm and stole a bag of buttons from the 90-year-old's bedroom.

He again fled the house and broke in to another neighbouring property by kicking down the back door.

A woman was home watching television at the time, but she ran out via the front door and called police.

Panicked by what had happened, Wheldon showered and sat naked on the toilet with a bath mat over his legs until police arrived.

Constable Thomas Moir and Sergeant Felicity Boyd entered the house on Mann Street with guns drawn.

As Wheldon was about to be handcuffed he punched Constable Moir in the head, causing a physical struggle between the pair.

Sergeant Boyd used capsicum spray on Wheldon, but he continued to punch Constable Moir.

The spray was used a second time and it eventually disabled him.

Ms Dix had bleeding on her brain, a number of face fractures and broken dentures as a result of the attack.

She spent four days in hospital and required a number of follow-up appointments.

Mr Gray was also hospitalised and still suffers from his injuries.

He has permanently lost some lower peripheral vision in his left eye and is no longer able to work as a painter due to physical injuries he sustained.

Wheldon was sentenced to five years and six months' jail, with a non-parole period of two years and nine months.