Syndactyly as part of a syndrome

Syndactyly is most commonly an isolated finding which we believe is “simply” related to a failure of the cells to regress during development. This failure to regress means that the webspace does not develop ~ the 7th-8th week of gestation. We know that the apical ectodermal ridge is involved and signaling mechanisms including FGF-8. This manuscript from Al-Qattan (an expert and highly experienced hand surgeon) provides one pathway explanation: Al-Qattan publication 2019

While most kids affected with syndactyly are otherwise without a medical condition, there are a number of syndromes which can include syndactyly. A great resource on this is OMIM- the Online Mendelian Inheritance in Man, If you search syndactyly at omim.org, 480 entries are provided. A fascinating collection of conditions related to syndactyly.

One of these, #164200, is Oculodentaldigital dysplasia (ODDD), with more information at ODDD at OMIM. ODDD is caused by a heterozygous mutation of connexin-43 gene, with the 6q22 gene. There is a “typical” facial appearance and variable involvement of the hands, eyes, and dentition. What is important from a hand surgeon perspective is that the hand surgeon may be the physician to make the diagnosis. What this means, of course, is that hand surgeon should understand this diagnosis and work with a genetics team to confirm the diagnosis. I first learned of this diagnosis from a mentor, Marybeth Ezaki who previously worked in Dallas. Marybeth shared her work in this paper in the Journal of Hand Surgery on 73 patients: Ezaki paper.

I was given permission to share the photos of a child with ODDD. He is, obviously, incredibly cute, but I share here because his facial features are typical for this diagnosis. His father is also affected and was treated by another mentor of mine, Paul Manske, many years ago.