Kenneth Brown was placed in an armchair by his son Timothy after suffering a fall during a fire in his bedroom in Victoria Way in Stafford, Cannock Coroners Court heard.
But a day later, 94-year-old Kenneth was found dead in the chair by his son, who then, instead of calling 999, left his father to decompose while continuing to live in the home.
The court was then told how a neighbour then called round on October 18, entering the hall and looking into the living room where Timothy was sat with Kenneth.
Timothy had been his father's sole carer for more than 10 years after his mother had passed away in 2004. The pair were described as 'recluse with hardly any visitors'.
A post mortem was unable to ascertain a cause of death because of the decomposition of the body, but it did reveal a number of fractures to Mr Brown's ribs - which were put down to a fall out of bed during the fire by investigators.
DC Andrew Weatherley from Staffordshire Police told the court how Timothy, who was not at the hearing, had said he had woken in the night and seen smoke coming from his father's room.
He had dragged him into the lounge and sat him in the armchair, DC Weatherley said.
However, Timothy said he woke the following day to find his father had died.
He told police he did not call 999 as he could not come to terms with it.
A statement from the neighbour said: "The back door was open, from the kitchen I could hear the TV was on loudly in the living room. Tim was in there watching TV. I spoke to Tim for a few minutes from the hall, before I opened the door fully. As I looked at the chair I wasn't sure what I was looking at. I could see a skull, I was very shocked."
Timothy was arrested, but after the fire service found evidence of the blaze and an investigation judged the fractures were caused by a fall, Staffordshire Police decided it was not in the public interest to prosecute him.
DC Weatherley said: "There was no obvious motive for him to cause the death of his father and it was decided he should not face criminal charges."
Senior Assistant Coroner Mrs Margaret Jones said: " It is a very sad case indeed. His son failed to deal with his father's death appropriately. The pair were very reclusive until the alarm was raised by a neighbour."
She added: "It is not possible for me to conclude that this was an accident as there is one piece of the jigsaw missing. Kenneth was last seen alive in April and his body was found in October but because of the decomposition of the body a cause of death cannot be ascertained."
She concluded an open verdict over his death.