Overuse injuries occur over time due to stress on the muscles, joints and soft tissues without proper time for healing. They begin as a small, nagging ache or pain, and can grow into a debilitating injury if they aren't treated early.
You want to upgrade from your current racquet - maybe you’re seeking more power, more control, more comfort... or a little of all three. Whatever your reason(s) for purchasing a new racquet, you have some basis on which to make your decision.