Definition of welt. 1 : a strip between a shoe sole and upper through which they are stitched or stapled together. 2 : a doubled edge, strip, insert, or seam (as on a garment) for ornament or reinforcement. 3a : a ridge or lump raised on the body (as by a blow or allergic reaction)b : a heavy blow.
The list of signs and symptoms mentioned in various sources for Polydactyly includes the 4 symptoms listed below: 1  More toes than normal. 2  More fingers than normal. 3  Extra digit on hand. 4  Extra digit on foot. 5  more information...Â».
Causes and symptoms. Polydactyly and syndactyly are conditions that occur in the developing fetus. Most often these conditions are caused by genetic factors. Both polydactyly and syndactyly can be caused by the presence of an autosomal dominant trait.