Accused of child abuse. But was his baby a victim of brittle bone disease?

Martin Smith was convinced that if you were innocent of child abuse, you had nothing to worry about. That was until last June, when his illusions were shattered. His two-month-old baby suffered a broken leg and he and his wife were charged with grievous bodily harm.

Mr Smith (not his real name) now believes that his baby was a victim of "temporary brittle bone disease", a condition which is causing controversy in the medical world.

Mr Smith's son, Tom, now 11 months old, was born seven weeks premature. At only eight weeks old, his mother noticed he was in pain and took him to the GP, who suggested an X-ray. That revealed that he had a broken leg, and further tests showed seven broken ribs and a broken collar bone, injuries that doctors estimated had occurred about four weeks earlier.

Since then, Tom's parents have maintained that they are innocent and waged a ceaseless campaign to get their child back.

They have several factors on their side. They have been allowed to keep their other two children at home, the police have dropped the criminal charges and the baby has been allowed to stay with his aunt, rather than going into care - but he is still under a child-protection order.

The Smiths have always believed that Tom must have some sort of medical condition, arising either out of his prematurity or from his mother's medical history - she had Hodgkin's disease before he was born.

Now they have found an expert, who has another explanation. Dr Colin Paterson, a senior lecturer in medicine at Dundee University, who has examined the baby, claims that he is suffering from a condition which he has dubbed "temporary brittle bone disease". He believes that this is a variant of the well-recognised bone disease, osteogenesis imperfecta (OI), which is an inherited disorder of the connective tissue.

Dr Paterson, who has studied. brittle bone disease for more than 20 years, recently published a study of 39 children whom he thought suffered from this temporary form of the disease. They had all suffered fractures in the first year of life, the fractures were found by chance when an X- ray was taken, and, in many cases, the children had no signs of bruising.

"It is a very distinctive syndrome, the symptoms of which mimic the symptoms of non-accidental injury. It has often been misdiagnosed as child abuse. It is more common among twins and premature babies," he said.

Dr Paterson, who has appeared in court cases and has been responsible for reuniting a number of children with their parents, wants to see the syndrome (which he thinks may be caused by an enzyme deficiency) recognised by paediatricians and radiologists.

The problem is that Dr Paterson is one of the few doctors in Britain who thinks that the condition exists. The vast majority of paediatricians do not believe that there is a temporary version of brittle bone disease.

A conference, being held in Edinburgh next Friday by the Royal College of Radiologists, will address the issue of how to diagnose non-accidental injury.

Dr Christine Hall, consultant paediatric radiologist at the Great Ormond Street children's hospital in London and co-author of an article in this month's Paediatric Radiology journal, which disputes the existence of the temporary condition, admits that care needs to be taken in distinguishing between brittle bone disease and child abuse.

She says there are four types of OI - three of which are easy to diagnose. The first, which is relatively mild, is characterised by the child having blue sclerae (whites of the eyes), the second is invariably fatal and the third is identifiable by the child's badly deformed bones.

There is only one type that is occasionally difficult to distinguish from non-accidental injury - known as Type 4A. But this is exceptionally rare. "One paediatrician has calculated that in his city of Sheffield, doctors can expect to see a case about once every 100-300 years," Dr Hall said.

"The hypothetical condition [temporary brittle bone disease] bears a striking similarity to many cases of non-accidental injury. I would suggest that they are the same condition but with different labels depending on the credibility of the child caretaker's explanation. "I know of one case, where Dr Paterson's theory was accepted, the baby was taken off the `at risk' register and returned home, and subsequently died," she added.

Dr Paterson, however, remains convinced. The problem for the accused parents is that they do not know where to turn. Tom's grandfather said: "There should really be a self-help group to turn to. We do not understand the system and feel completely alone."