I'm a rising sophomore in high school. I've been enjoying tennis since the beginning of my freshman year. My wrist started hurting since around a week ago. I've located the site of pain to be the joint between the triquetrum and the hamate (see here for the bone locations). It doesn't hurt when my wrist is straightened out, but if I bend it outwards - for example, putting my hands on my hips, or when it bends naturally on the forehand or the serve - it sends a jolt of pain up my arm. Strangely enough, I can feel something slide in and out of the joint, and the pain only occurs when it's slided out. Last night, I borrowed my sister's hair tie to keep it inside the joint, and so far it hasn't hurt again; whatever it is must be staying inside for now. Does anyone have a guess as to what this might be? I've had tendinitis before, but the sac on top of my wrist has long since dried out (after six times of manually bursting). I've googled bursitis, but nothing specifically address the problem between the two bones mentioned above. fyi, I use the Wilson KBlade 98. Thanks for any tips you can give.