I have actually seen video saying modern technique is better for the knees as you use more open and semi-open stances where a classic forehand usually closes the front knee resulting in more knee twist on the lead leg.
I think you are referring to the back or "load" leg. I would think the answer is trying semi-open stances to reduce the twist angle.
My opinion is you do want a bit of knee bend and lift and rotation from the core so you cannot eliminate loading, lifting and rotation. Also, think lift as you rotate off the load leg. Lifthing reduces torque on the knee.
You might want to start a lower body strengthening program too. Google meniscus rehab exercises and you'll get the basics: front, rear, and both sides leg lifts, squats, heel raises and lots of streching. The theory is to strengthen the muscles groups above and below the knee and to keep the lower body flexible.
I am 56 and had L (front knee as I'm right handed) knee meniscus surgery last summer.
Also, mid 40s was the age when injuries started catching up with me. Don't over play and hit the gym.
Last edited by TennisCJC; 05-14-2013 at 07:25 AM.