Most of your scores are pretty good. Lumbar spine is excellent, hip is good, the femoral neck tends to be worse but is still not osteoporosis. Gosh I would hate to take a med just to address my right forearm but yours is an unusual situation.

How did the replacement of shoulder and elbow affect the forearm?

At 82 you might be able to do Prolia and just stay on it. My friend is the same age and is doing that. Or you could do a bone builder. But I am curious what doctors say about addressing that one body area when everything else is pretty good. It makes me think of wrapping that forearm in bubble wrap!!!! Let us know what your doctor(s) say and maybe a second opinion would help too.