I use comfrey tincture (nickname is boneknit), available at health food stores for minor fractures with success. When my FIL fell and fractures some foot bones, he tried it and liked it. His comment also included that his trigger finger relaxed and he really liked this. Coincidence? or causal? I don't know but it's inexpensive and worth a try. I would apply it directly to the skin over the hurt bone (thumb) and add it to water for drinking (it says not for internal use but in my herbal training I was told otherwise).
Laurie