uncharted waters

The limits of current medical knowledge on fractures and rickets, discussed in the case of A Local Authority v M and Others 2013

http://www.familylawweek.co.uk/site.aspx?i=ed127031

This was a case where His Honour Judge Hayward-Smith had considered a fact-finding hearing about a child who had suffered multiple fractures, including a skull fracture. At that hearing, the medical evidence had been unanimous that the child had been suffering from rickets but that the injuries had been caused by the parents, and hence the findings were made.

Subsequent to that, the judgment in Al Alas Wray was published, and that obviously highlighted the possible connection between Vitamin D deficiency, rickets and fractures in children.

The case came back before the Judge, who authorised some fresh experts, to look specifically at whether the presence of rickets in the children might mean that the fractures were not caused deliberately by the parents.

The medical evidence here was not simple, and not agreed, and the Court had to not only address the conflict between the medical evidence, but also to address the fact that the issues in question were butting up against the edge of what was known medical science and attempting to extrapolate from that what might be learned in the future.

 In particular, it became clear that what was not known at this stage, and did not exist in the research was

(a)   Whether having rickets meant that a child could suffer fractures more easily or with less force than a child without rickets would require to cause the same injury; and

(b)   If so, how much more easily, how much less force?

(c) The extent to which rickets affected the healing speed of fractures, and thus the reliability of usual dating techniques to decide WHEN the injury happened where rickets is a feature.

On the first issue, the experts were agreed that the existing research on animals did strongly suggest that for animals there was a sufficient link between the presence of rickets and fractures occurring more easily or with less force to be confident that a causal relationship existed, and that this PROBABLY mean that the same was true of humans, and human children too.

On the second and third issues, there was no certainty at all and no research evidence yet to point clearly in either direction.  (Again, with animals, the research showed that rickets did impact on the healing rate of fractures)

One of the evidential issues that arose was whether, within the body of children who have rickets (and are known to have rickets) fractures and multiple fractures as in this case was a common feature, a fairly rare feature or an almost unheard of feature.

 The problem here was that although the Court had the benefit of two experts with a lot of experience on the issue, their experience differed, and neither had the raw data or research, just their own observations. One thought it was almost unheard of (and thus that with multiple fractures NAI was a more likely explanation for the injuries), the other felt that it was fairly rare but within his own experience.

Is the multiplicity of fractures significant?

33. As the evidence developed this issue appeared to me to lie at the heart of this case.  Professor Gardner went so far as to say that Professor Bishop’s experience in this area led him to conclude that this is a case of non-accidental injury.  There is no doubt that Professor Bishop is a very distinguished expert in this field.  He was described by one of the experts as knowing more about this field than anyone else in Europe.  Professor Bishop said during the course of his evidence:

“In Sheffield we see approximately 500 children in any one year.  The majority will have conditions leading to bone fragility, the majority being osteogenesis imperfecta [which is not rickets].  I have been involved in this area since 1987 with babies, including premature babies, and older children since mid-1990s.  I have seen cases of rickets and the number reaches three figures.  [He did not go further as to what he meant by three figures, but it is clearly a large number of children]. 

“Of the children that I have seen with rickets, as far infants are concerned and indeed older children, I have only had three or four with fractures and only one had multiple fractures.  The children, in my experience, with multiple fractures are mobile and not as young as M who would have been immobile, but in one case a child was so ill that the bones could hardly be seen on x-ray and there were multiple fractures; and in that child, indeed, the rib cage had fallen in, it was very severe de-mineralisation of the bones.” 

That evidence reflected what he had said at the experts’ meeting.  The transcript of what he then said reads as follows:

“My concern remains that I have seen a number of cases of rickets which are more severe than this where there has only been one fracture.  I have not seen any other child in my own clinical experience with this number of fractures with rickets or, alternatively, in the literature with a description of this number of fractures in the presence of clinically apparent rickets.  So to me, this is a disproportionate number of fractures and it was actually the reason that I agreed to take this case on in the first place because it was unusual and because I was expecting, when I reviewed the child clinically, to find evidence of some other underlying bone disease that would provide an explanation for the fractures not the rickets.” 

Professor Barnes then asked the question whether that reflected Professor Bishop’s experience in relation to children under the age of six and Professor Bishop said:

“Yes, certainly, it does reflect my experience that it is unusual to see this number of fractures in an infant with vitamin D deficiency, rickets, at this age and that is an experience that goes back over quite a large number of years.  Before I did bone disease I did a lot of neonatology for ten years and we did see from time to time infants in the premature baby unit who had fractures as well, although the aetiology there is quite different.  But this is a stand out from my perspective over that long period of time.”

Professor Barnes then asked him whether his experience had reached the literature and Professor Bishop answered: 

“No, it has not reached the literature because, as I say, it is a scattered experience over a long period of time and I have not kept the case notes of each individual child seen over that period so it is a cumulative experience.  I have talked as well with a number of colleagues about what their experience has been and the general agreement, I have to say, is that one fracture is not unusual in rickets, occasionally two, but, you know, more than that, four, no, we don’t see that.” 

He then said in further evidence:

“Even with that child that I referred to with very severe rickets, there were only three or four fractures.  The majority of rickets cases don’t have a single fracture.  Given the likelihood of multiple fractures in the context of rickets, it is more likely in this case that there has been a use of excessive extraneous force.”

He went on to say:

“There is no objective measure of force required to produce fractures.  In normal children, multiple fractures would indicate abuse.  Multiple fractures in rickets is not borne out on the evidence of my experience, but there is very little published evidence in relation to children under six months.  We x-ray babies all the time.  If rickets was responsible for a lot of fractures we would be seeing multiple fractures in children with rickets and we just don’t see them.  In some parts of the world many children have rickets and there are no reports of multiple fractures.  A fracture, and certainly multiple fractures, is uncommon in rickets.”

That is strong evidence from a distinguished source and I take it very seriously, as indeed I did at the last hearing.

34. There is no objective research and no literature to assist much in this field.  Professor Nussey told me that animal research indicates that rickets in animals greatly reduces the force required to break bones and all the doctors agree that that is likely to be so in humans.  Reference was made at this hearing, as at the last hearing, to the Chapman study, but it is of limited value because of the limited number of children involved.  Professor Nussey’s written report includes the following passages:

“The question as to whether the presence of several fractures rather than one is an indicator of abuse rather than general bone fragility is impossible to answer in the absence of any objective measure of the change in the tensile strength of bone in rickets.  Skull fractures are said to be unusual in rickets, but they have been reported.”

Professor Nussey said that he deferred to Professor Bishop’s experience in this area, but I did not take him to be wholly jettisoning his own evidence. 

36. Professor Barnes’ experience of children with rickets having multiple fractures differs from that of Professor Bishop. The reason for the difference in their experience is unclear, but it has been suggested that more x-rays are taken in the United States and so more fractures come to light.  In the United States most cases of rickets are referred to major centres, whereas in the United Kingdom they tend to be dealt with locally. 

In the concluding passage of the analysis of the medical evidence, the Judge said this:-

All experts agree that there has been little research into the nature of the issues in this case.  Rickets has been curable since the 1920s and there has, therefore, been no pressing need for such research.  All experts agree that the issues in this case should be approached with caution and that there were many unknown factors including the amount of force required to cause a fracture.  Professor Bishop said that he could not be sure to the criminal standard of proof that this was a case of non-accidental injury.  He put the balance of probability at about 75%.  Both Professor Nussey and Professor Barnes say that there is insufficient evidence to say whether or not non-accidental injury has occurred in this case and that the evidence is consistent with innocent parents. 

43. At the last hearing the medical evidence pointed inexorably to the findings I made.  This hearing has been very different.  I am now doubtful whether the parents would necessarily have noticed any of the fractures, apart from the humerus and the skull to both of which they reacted appropriately.  I have conflicting evidence as to the relevance of multiplicity of fractures.  I bear in mind that the parents have given no explanation for the injuries apart from a tight garment pulled over the head and a possible knock on the head in the car, but – given the nature of the rickets, the uncertainty of how bad it was prior to 2^nd January and the lack of knowledge of how much force would be required to break a bone – it would, in my view, be wrong to draw the inference that a lack of explanation from the parents indicates non-accidental injury.  For all those reasons, I am not persuaded on the balance of probability that the parents did cause these injuries to M.  I do not find, therefore, that the section 31 significant harm threshold has been crossed. 

44. I add one final word about the medical evidence.  I have great respect for all the experts in this case. They are all very impressive.  I would not wish to be taken as criticising any of them or rejecting the expertise of any of them.  This case involves areas of scientific uncertainty where there has been a paucity of research for reasons I understand.  Medical experience differs and caution is required, as indeed all the doctors involved accept. 

The Judge could have done nothing other than this, I think. We have reached a point in determining non-accidental injuries where rickets is demonstrated to exist where we simply do not know, and are not likely to find out any time soon, whether it makes such a difference that injuries that appear deliberate are in fact caused by relatively minor trauma; and where such doubt exists, the benefit of it has to be given to a parent.

It is an invidious position for all involved to be placed in – for the parent who can’t find the definitive answer and might end up being separated from a child temporarily or permanently, for a social worker who is trying to make a decision about whether the risks mean that such a separation should be sought, for the doctors on the ground trying to reach a conclusion, and for Judges who are having to make a decision as to whether what on the face of it are awful and serious injuries may have their causes in biochemistry outside the parents control or responsibility.

One thing is for certain, in any case of suspected fractures to children, getting an answer as to whether rickets or vitamin d deficiency are a clinical feature and getting that answer early will be vital.