When I first noticed this flower in Damascus, PA I called it Airplane Flower, since the bloom resembles an airplane with wings and propeller. Since then I have noticed it as a dominant, though small, under-story flower. These photos are from yesterday in Glen Spey, NY.
I have not encountered anyone who uses Fringed Polygala as a medicinal, though according to Iroquois Medical Botany by James W. Herrick it was considered a powerful medicinal plant by the Iroquois. Such classification was based on the strength of the medicine, how or where it grew, and the nature of the illnesses it cured. Fringed Polygala attained status as a powerful medicinal by nature of it being evergreen and because of the diseases it was used for (including that some of the illnesses came from settlers).
This is another example of a common herb that has been largely forgotten by herbalism. We disregard it, while the Iroquois formerly classified it as a powerful medicinal plant. Of course, one question is whether the population would be so abundant if we did desire it for use. It's relative abundance in our forests indicates some toxicity, as the deer are leaving it alone. I have not observed them eating it, but perhaps they do nibble some. (Toxicity, as alluded to above, is also a criteria of Iroquoian powerful medicinal plants.)
Polygala paucifolia POLYGALACEAE (MILKWORT FAMILY)
Used by Iroquois for abscesses on limbs, internally as infusion and externally as poutice. It is also boiled into a wash and used on boils. It is used with Pipsissewa (Chimaphila umbellata) for syphilis, including for babies with sores. It is used with Shinleaf (Pyrola elliptica) for sore legs, tied on as a poultice "if a man is a good worker and someone wants to spoil him".