Two questions

In your experience, is it possible to get rid of a hand knot? I've had one myself that was massaged out by a professional, but reappeared, and it's probably been there for a month. No idea how to get this thing out, the spot is super tender after self-massaging it.

If a tennis player is feeling hand pain (in their fingers mostly, especially when stretching them away from the palm), is this more likely to be a result of playing with a racquet handle TOO THICK or TOO THIN?