You are quite correct about the typical CTX reference range. I had forgotten it simply reflects what was observed among healthy folks in various age groups.

Not very helpful therefore in trying to understand what might or might not be happening with a very low CTX score and whether/why it should be concerning.

Now that I have a bit better grasp of the concept of bone remodeling, I would be concerned about a low CTX score for the reasons given by McCormick.

Bone density and bone strength might be related but are likely not the same. While osteopenic, I took 2 very bad falls, each on a hard surface. One should have resulted in a broken wrist; the other in a broken bone in the hip area. They were both painful and took forever to get better....but no bone breaks.

Those 2 incidents began my personal questioning about bone density as the test for determining treatment. And about bone density increasing with bisphosphonate treatment, when the mechanism of that increase may be more like slapping on a coat of paint without proper prep work.

Surely this area of medical research and practice can do better. Best of luck with your bones.