I have had a pretty noticeable (over the last couple of weeks) ditch developed in my right thumb nail bed going from side to side. There has been no injury (I have pretty bad osteoarthritis in that hand and I definitely would have noticed LOL)...no bruising. Just a couple of pinprick spots underneath the ditch...very odd. Have been having major inflammation issues (microscopic colitis, treated for H. Pylori, GERD, possible issues with gluten, etc. ... ongoing treatment @ Loma Linda) ... badly worsening arthritis. Wondering if that could be the cause, or if this sounds like something else? I ve never had any nail issues before, and I m very puzzled.