I am a 65 Yr old female with a longitudinal blueish stipe on my right thumbnail.It does not originate from the matrix. My family doctor thought it was from an injury that would begin to grow out.In the two weeks since he saw it it has not changed.It is possible I did have an injury to that digit. I am on blood pressure meds, anti anxiety meds and naproxen. I am starting to become concerned.Also I had knee surgery two months ago for a damaged meniscus.