A father high on cannabis broke his baby daughter's leg because her crying woke him up, a court has heard.
Timothy Pugh was jailed for three years after admitting inflicting grievous bodily harm on his four-month-old daughter.
Judge Jonathan Durham Hall QC said Pugh, 26, posed an "extreme risk" of severe injury" to any child alone with him.
Pugh, from Cardiff, initially claimed the baby caught her leg in her cot.
But doctors who examined her said the injuries were so severe they could not have been caused accidentally.
Cardiff Crown Court heard that Pugh, of Maelog Place, Gabalfa, had been sentenced to 16 months' imprisonment in 2002 for inflicting GBH on a three-month-old baby.
Eugene Egan, prosecuting, said the latest incident happened in the early hours of 15 May. He told how the baby had just been fed and her mother, Alice Cordt, was sterilising bottles downstairs.
"An occupant of the house called Kirsty Jones heard some whining from the baby and that was followed by a more distinctive sound. The baby was plainly distressed and in pain," he said.
Pugh brought the baby downstairs, saying there was something wrong with her, and she was taken to hospital in a taxi.
"A fracture of the right femur was confirmed at the hospital," Mr Egan explained.
"It was described as a spinal fracture needing considerable and excessive force."
Pugh was arrested at the hospital. When questioned by police, he admitted having been high on drugs.
He claimed the injuries were caused when the baby got her leg caught in the cot but doctors who examined Keely said the injuries could not have been caused accidentally.
'Moment of frustration'
Jeremy Jenkins, defending, said Pugh had been tired through lack of sleep.
"There was an aggravating situation of a young baby, who would not settle and was grizzling, and in a moment of frustration when the defendant lost his temper he tried to stop the baby's grizzling and caused the injury," Mr Jenkins said.
He added: "This defendant never really had a chance in life. He does accept however that what he did was wrong and does accept that it means a considerable period in custody.
"It will be worse for him in jail because of the attitude taken by fellow prisoners towards people who commit these type of crimes."
Sentencing Pugh, Judge Durham Hall said he gave him credit for pleading guilty "at the earliest possible opportunity", but said what he did was "exceptionally serious".
He added: "You twisted and bent her lower leg causing a dislocated fracture of the femur. The distress that child must have suffered would be difficult to quantify.
"You are clearly, whether or not you formed the lasting intent at the time, not fit to have supervision contact with any child because any child alone in your presence is at extreme risk of severe injury."