A six-year-old boy allegedly murdered by his father and his girlfriend suffered the same level of fatal brain injuries as a car crash victim, a trial has heard.
Arthur Labinjo-Hughes was 'banged' to the head and suffered multiple bleeds on the brain as a result of 'shaking', Dr Stavros Stivaros told Coventry Crown Court.
Arthur's dad Thomas Hughes, 29, and his then-partner Emma Tustin, 32, both deny murder.
Dr Stivaros, the first medical expert to give evidence at the trial, said it was 'inconceivable' that Arthur 'self-inflicted' all of his fatal injuries.
The child collapsed at Miss Tustin's home on Cranmore Road in Shirley, Solihull, on June 16 last year.
He died at Birmingham Children's Hospital the following day having suffered a traumatic brain injury.
Miss Tustin has pleaded guilty to one count of child cruelty but denies three further charges of the same offence.
Mr Hughes, of Stroud Road, Shirley, also denies all four child cruelty charges.
Dr Stivaros, a specialist in child brain and spinal scans, told the jury that Arthur had bleeding across 'multiple different sites' in the brain which was 'more in keeping with shaking than impact'.
The court heard that CT scans were performed on June 16 while Arthur was still alive at 4.25pm and 8.01pm.
Dr Stivaros said: "Between the two scans it became worse and worse in that three-and-a-half-hour period."
Dr Stivaros told the court that swelling was a 'sign of being banged' and that Arthur had multiple locations of swelling on his head.
The expert stated there were 'at least four impacts' but no skull fractures.
He also revealed that by the time of the second scan Arthur's brain was 'reaching a point that would not allow the patient to survive'.
He then compared Arthur's injuries to those he has seen in children who have been involved in serious car crashes.
The expert said that while 'impacts' could explain the bleeding in some areas of Arthur's brain, they could not account for it in other parts, which he attributed to shaking.
Dr Stivaros confirmed the force required to inflict such damage could be described as 'violent', jurors heard.
Asked whether he believed Arthur could have self-inflicted his injuries, Dr Stivaros said: "In this instance, you have a child who is six, on all fours and has banged his head from a crawling position on to the floor?
"First of all that would be impact, that would not be shaking. It doesn't explain the constellation of injury findings we have seen in this case.
"Also, how much force is Arthur going to be able to generate when on all fours on the ground?
"He can't use his muscles to accelerate the fall to the ground. He would have just fallen by gravity.
"Is that likely to have caused the injuries we have seen? No, I stand by my comments. It's inconceivable."
Previously the jury has been told Miss Tustin and Mr Hughes:
Isolated Arthur from the rest of the family
Made him spend up to 14 hours a day in the hallway
Deprived him of water and poisoned him with salt
Arthur had been in the full-time care of Mr Hughes after his mother, Olivia Labinjo-Halcrow, was accused of killing her new partner, Gary Cunningham, in February 2019.
She was jailed for 11 years in July this year after being found guilty of manslaughter.
The trial continues.