This prospective study of the relationship between neonatal foot deformities and associated developmental dislocation of the hip (DDH) is significant as it is a "dogma buster". The accepted teaching that all foot deformities are a risk factor for associated DDH has been disproved by Paton and Choudry… at least in the Blackburn district of the United Kingdom. The authors have convincingly shown that congenital talipes equinovarus (CTEV) is not associated with an increased incidence of DDH, hence this common neonatal foot deformity is not a risk factor. They have recommended that such children no longer need to be subjected to screening for DDH and that in the UK Guidelines, the term "foot deformity" be redefined as "congenital talipes calcaneovalgus and metatarsus varus" in which a statistically significant association with DDH was demonstrated.
However, we must be careful that we don't "throw the baby's hip out with the bath water". The authors' data is very relevant to the Blackburn district and the guidelines for DDH risk factors could safely be altered here as well as in the entire UK if the Blackburn population can be shown to be a microcosm of the country. We must be cautious in applying these results globally especially in areas where CTEV and/or DDH have a much higher incidence than in the Blackburn district. In the Middle East for example where I am currently in practise, both CTEV and DDH have a very high incidence and the association of both congenital conditions have been personally encountered anecdotally on several occasions.
As well we must remind ourselves that the authors excluded all neurological and syndromal conditions from their study which often have associated CTEV and DDH e.g. arthrogryposis, spina bifida, or Larsen's syndrome. Since syndromes are not always self evident, it would be a shame to miss a DDH in a child with a syndromic CTEV because a DDH screen was not indicated by the "guidelines".
My approach to screening for DDH is simply to always examine the hips in any infant up to one year of age whether they have a risk factor or not, i.e. the indication for a clinical hip screening is the mere presence of a hip!
We should all try to instil this clinical compulsion for DDH examination in all family practitioners and paediatricians.
Paton and Choudry have designed and completed an excellent longitudinal observational study that has challenged the accepted dogma that all foot deformities are associated with a higher incidence of DDH. Their patience and perseverance in bringing this 11 year study to a successful conclusion is commendable since we all know the many pitfalls of longitudinal studies. In their environment, altering the guidelines to avoid sonographic studies of the hips in neonates with CTEV is very reasonable. Those of us practising in areas of the world with a higher genetic predisposition to either CTEV or DDH should avoid following suit until we have performed our own studies to clarify the risk/reward of using sonography of the hips to detect DDH in children with congenital foot deformities.
Dubai, United Arab Emirates