What Is The Cause And Treatment For Tenosynovitis?

Have a 6 month old and thought I had what i read is tenosynovitis or "mothers wrist" but I've rested them and changed how i hold and pick him upand my right one is still quite painful. Even the slightest nudge almost bring tears. I've also notice the vein on my wrist (same side as thumb) is swollen. Causes? Solutions?