'Extreme pain' of abused baby Amy

Amy Howson was also malnourished and dehydrated

It was one of the most shocking cases of child abuse seen in Doncaster in recent years.

Amy Howson was just 16 months old when her father held her over his knee and broke her back in two.

The injury led to spinal shock and rapid unconsciousness and Amy died in hospital hours later.

The fatal attack in December 2007 followed weeks of abuse during which James Howson slapped and punched his daughter, leaving her with fractured arms, legs and ribs.

Amy was also malnourished and dehydrated at the time of her death.

At Howson's trial last year, a prosecutor said Amy "must have been in extreme pain and in poor physical condition for a period of weeks prior to death".

Det Supt Carl Sturgess, who led the investigation, said: "The catalogue of horrific injuries have been some of the worst I have ever seen in 30 years of policing."

Howson was jailed for life last October, with a minimum term of 22 years.

Amy's mother Tina Hunt was also convicted of cruelty.

'Not preventable'

Now an investigation into Amy's death has found that agencies missed "three key opportunities" to intervene in the year before her murder.

Howson had a troubled history and had been violent towards women when he was young, but he had no previous convictions.

Yet in a chilling prediction when Howson was expelled from school, his teacher noted in a report: "This boy will commit a murder before too long."

A serious case review found that Amy's murder was "not predictable or preventable" but there was "sufficient information held by agencies to conclude that the child was at risk of significant harm".

Amy was one of seven children who have been the subject of serious case reviews in Doncaster since 2004.

Howson and Goddard have both been given life sentences

Another was 11-week-old Alfie Goddard, from the Toll Bar area of Doncaster, who died of head injuries at Sheffield Children's Hospital in May 2008.

A report has also found several failings by child services and other agencies in his case.

It said some agencies, including the police, had a "high level of involvement" with the family and should have concluded that Alfie was "at risk of significant harm" from his father.

But the report said the boy was killed in a "spontaneous and violent" attack and his death would not have been preventable.

Goddard shook his son, squeezed him hard enough to fracture three ribs and dropped Alfie down the stairs in a "moment of anger" when the boy would not settle.

He had been drinking and had smoked several cannabis joints before the attack.

Goddard was jailed for life after admitting murder and told he would serve at least 11 years in jail. Alfie's mother Lindsay Harris was given a 12-month suspended jail term for lying to protect Goddard.

Sentencing the pair in January, Judge Mr Justice Beatson described the boy's death as "truly tragic".

He said: "A young life has been lost and the two of you are marked by the consequences of what has occurred for the rest of your lives."

But the judge said social services could not be blamed for Alfie's death, telling Goddard: "You accept, as does Miss Harris, that what happened was the responsibility of those who were present in that house."