Here is the answer to another question about concerning PRP.
There is no data on the use of PRP for meniscus surgery so far. Many years ago, isolated meniscus repair was routinely enhanced using a fibrin clot which is similar to PRP. Again, this type of application makes sense but there isn't any solid information concerning its use in this area yet.
Adding PRP to meniscus repairs is best discussed on an individual basis with your surgeon.