When there is a tear in the white zone it cannot be repaired as the area will not have blood supply. Trimming of the white zone tear is beneficial in preventing further damage to the knee. But as the meniscus is not complete like how it had to be there will be slight alteration in the biomechanics which will be present and that will affect you 10 or 15 years down the lane.. Risk vs benefit ratio when taken for white zone tears shows that trimming of the white zone tear is beneficial than causing risk.