aetiology
Last reviewed 01/2018
The aetiology of congenital syndactyly is thought to be a deficiency of the normal wave of apoptosis that occurs between digits in weeks 4-8 of intrauterine life. Triggering factors may be extrinsic steroid exposure or fibroblast growth factor receptor deficiency.
Ogino(1) has suggested a failure of normal digital induction as a cause of syndactyly that is associated with polydactyly and typical cleft hand.
Alternatively, in a minority of cases an intrauterine amniotic band may traumatize the space between digits and subsequent healing leads to fusion by the time of birth.
Ref: (1) Ogino T et al. (1986). J Hand Surg 11: 364-371.