Pros and cons of new hip dysplasia technology for newborns
The technique is not yet validated and may not be used in the UK anytime soon. But for those who know the trauma caused by a late diagnosis of hip dysplasia – any positive developments in early detection are most welcome.
If we do see statistical shape modelling in the UK, we should expect more cases of hip dysplasia to be diagnosed early. The benefit of early detection is that treatment in the first few weeks and months of life is usually straightforward and highly effective – resulting in normal hip development and no increased risk of problems in later life. Delays in diagnosis often mean not only invasive treatment in childhood, but also issues in adulthood with risks of premature arthritis and the need for hip replacement surgeries.
I have run several medical negligence cases involving misread ultrasound imaging – generally this involves either an incorrect assumption that the hips 'alpha angles' are within normal range, or where there is an overemphasis on those alpha angles, and a failure to consider other indicators, such as an abnormal contour of the acetabular brim, or poor coverage of the femoral head by the acetabulum. New techniques in ultrasound providing more effective screening should help to remove the human error element and reduce these types of cases.
So, that is the good news. The unfortunate news is that the NHS still has no plans to bring in universal ultrasound hip screening for newborns. This means that most late diagnosis of hip dysplasia cases will still occur, no matter how effective new ultrasound techniques are. That is because for the patient to benefit from effective screening, they first have to have an ultrasound. Sadly, most cases I see are a result of a failure to refer for a scan in the first place.
Very little has changed in the UK around picking up cases of hip dysplasia in newborns. The tests performed during the newborn physical examination, known as the Barlow and Ortolani tests, have been around since man first walked on the moon. These tests are well-known to be poor at picking up hip dysplasia – false negatives are common.
There has been pressure on the NHS for some time to introduce a system of hip screening for all newborns. One reason behind this reluctance is that ultrasounds can generate false positives – resulting in 'over-treatment' and unnecessary costs and risks to the patient. But with new technologies such as statistical shape modelling, the risk of over-treatment is reduced and the benefit of screening all newborns to the NHS, particularly long term, is greatly increased.
These new developments will likely have the most impact in countries were universal hip screening is already in place. Where hip screening is not routine, as in the UK, the new and impressive techniques can only ever be of limited use.