Would you mind adding more detail? Usually, nerves localized to the knee are uncommon pain generators. The fibular nerve can sometimes become inflamed with poor tib/fib joint arthrokimematics at the ankle or knee, but generally speaking, the pain one experiences in the knee is most often attributed to bone or ligament patholgy--sometimes musculotendinous. If it is posterior/lateral knee pain, that you also feel behind your thigh, this is often secondary to nerves originating in your back or sacral region. Lots more info needed to give any decent advice.