I humbly disagree with the authors of a Photoclinic case on bilateral clinodactyly of the fifth finger that was published in your January issue. Drs Alexander Leung and W. Lane M. Robson write: "In most cases, the condition is an isolated anomaly and is not of any medical significance. Clinodactyly is occasionally a minor manifestation of a syndrome such as Down syndrome, Seckel syndrome, Cornelia de Lange syndrome, Mohr syndrome, or Silver-Russell syndrome."
Clinodactyly itself is benign, but it is frequently associated with learning disabilities and behavioral disorders. It is considered a soft sign in the diagnosis of these conditions. Indeed, all developmental/behavioral pediatricians look for clinodactyly during their initial evaluation.
---- Daniel Nussbaum II, MD Developmental Pediatrician New Bedford, Mass
We appreciate the comments by Dr Nussbaum. While there is a belief by some clinicians that learning disabilities and behavioral disorders are more common in patients with isolated clinodactyly, there is no scientific evidence to support this impression. A Medline search does not reveal any data to substantiate this assertion.
Clinodactyly is observed in a variety of syndromes associated with learning disabilities, behavioral disorders, and other dysmorphic features. But in our experience, clinodactyly is seen more commonly as an isolated and benign problem.
We agree with Dr Nussbaum that the presence of clinodactyly or any other dysmorphic feature should encourage a search for other problems. But we respectfully disagree that the presence of isolated clinodactyly implies the presence of a more serious disorder. Because learning disabilities and behavior disorders are common problems in children, their association with isolated clinodactyly might be a chance occurrence.
---- Alexander K. C. Leung, MD Clinical Associate Professor of Pediatrics University of Calgary, Alberta Pediatric Consultant Alberta Children's Hospital
---- Wm. Lane M. Robson, MD Medical Director Children's Clinic Calgary