A doctor failed to properly examine a baby identified as being at risk two days before his death because she found him "cranky", the Old Bailey has heard.
The 17-month-old boy died in Haringey, north London, from multiple injuries, including a broken back, last August.
The prosecution told the court that the child had suffered the injuries before he was seen by Dr Sabah Alzayyat.
The baby's mother, her boyfriend, and Jason Owen, 36, of Bromley, south-east London, all deny murdering the infant.
All three had been living at a house in Haringey at the time of the baby's death on 3 August 2007.
The child's mother, 27, and her 32-year-old boyfriend cannot be named for legal reasons.
Other injuries to the boy included eight fractured ribs and a missing tooth, the court heard.
The mother and baby had been sent to a clinic at St Ann's Hospital, Haringey, on 1 August 2007, and the boy was seen by Dr Alzayyat, a locum consultant paediatrician, to check on his development.
Sally O'Neill QC, for the prosecution, said: "It is the prosecution case that he suffered these injuries before he was taken to the Child Development Centre, and if that is right, it is a cause for considerable concern."
Experts thought the child would have been in extreme pain and unable to move his lower limbs due to paralysis, she said.
Miss O'Neill told the jury: "This would have been evidenced at the very least by floppiness and could not fail to have been observed by a competent doctor who had examined him properly."
"Dr Alzayyat noted a number of bruises to the baby's body, on his face and his back and noted an infected area in front of his left ear and a fungal infection on his head.
"However, she decided that she could not carry out a full systemic examination as he was miserable and cranky.
"That may not seem to you or me to be the best reason for a consultant paediatrician to not fully examine a child who is known to be on the Child Protection Register."
Dr Alzayyat had prescribed antibiotics and referred the child for further tests.
But the court heard how the boy died two days later after receiving a blow which knocked a tooth out, which he swallowed.
Miss O'Neill told the court: "Over the last seven or eight months of his short life, he was subjected to a course of assaults of increasing violence."
She added that the death of a child in such circumstances was "likely to fill any reasonable person with revulsion".
In December 2006, the child's mother and her partner were arrested for assaulting the baby and bailed.
The infant's name was placed on the Haringey Child Protection Register under the categories of neglect and physical abuse, the court heard, and the boy was placed with a friend.
Tests on the baby's injuries proved inconclusive and he was returned to his mother, although the police investigation continued and there were regular visits from social workers, Ms O'Neill said.
The trial was adjourned until Wednesday.