She said when the sheet covering her was pulled back the [unsightly] wounds were revealed.
Crown prosecutor Steve Manning said in his opening address the woman was "someone who required care" and was "owed the necessaries of life" because she had heart disease, type two diabetes and osteoporosis.
He said Quinn's mother was essentially "bound" to the couch and had a severely ulcerated and swollen leg and covered in rotten skin when medical staff and paramedics found her in a "medically risky environment".
The Crown alleges Quinn "endangered the life of her mother" by not seeking the required medical care.
Crown witness Dr Caroline Young said she was taken through a dark corridor where she discovered the 82-year-old in the main living room with the curtains drawn and a bad "musky" smell.
Quinn had called a local medical centre, prompting Dr Young's visit.
Dr Young and nurse Helen McKenzie wore an apron and gloves as they lifted the blanket covering the elderly woman's legs.
"It was terrible, I was shocked," Dr Young said.
Ms McKenzie said Quinn's mother was "slumped right over to her right side" and appeared thin and pale when she entered the lounge.
She said there was nothing the pair could do to immediately "make it better".
"The wound had been there for some time. It was almost cavernous."
Quinn's mother reluctantly agreed for an ambulance to be called and was taken to hospital.
St John ambulance officer Emma Hubbard said the smell was "awful" and Quinn's mother, wearing nappies, looked "unclean and very weak."
She said it appeared the rotten skin had embedded itself into the blanket and leg rest. Ms Hubbard told the court while the paramedics attempted to transport the 82-year-old to the ambulance Quinn was obstructive and twice heard her say "shut your mouth mother" in an "unnecessary and threatening way".
Later, Ms Hubbard talked to Quinn's mother in the ambulance where the elderly woman said she tried to leave the couch at night while Quinn was sleeping and had been on the couch for years.
Quinn's lawyer Matt Dixon said there was no evidence the woman was dehydrated nor malnourished.
Quinn insists her mother was hard to care for and did not request medical care.
The trial continues today.
