It occurs to me that it might be useful to share what I have done / what I have learned about using metatarsal pads to address my left big-toe joint injury.
As described in my post last week, this pain is on the bottom of my left foot, at the bottom side of the big toe joint.
I ordered some commercial metatarsal pads from Pro-tec:
Nevertheless I tried them. The shape of these pads is not great for big toe pain as they do not fit quite right on the edge of the insole. I tried one on my left insole in my Hokas last week but found it uncomfortable, too big and not correctly positioned. Mid way through a run I stopped, took out the insole, removed the pad, and applied a wedge shaped piece of neoprene foam that I cut from a Dr. Scholl's work shoe insole. (I had bought these to try because Dr. Scholl's athletic shoe inserts all have rather obtrusive plastic arch supports. The insoles were however too mushy to use for trail running). Here is what these look like after harvesting material for construction of metatarsal pads- top side is grey fabric coated, bottom side is black, what appears to be neoprene: