I understand that one of the purposes of the meniscus is to cushion the joint. With a good chunk removed, your knee will be more susceptible to shock. That's why I suggested trekking poles and a lighter pack.

I use a knee brace on long downhills, but have found that keeping those leg muscles strong is the most important thing!
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey