These C-shaped shims disperse weight over a larger area and adds stabilization of the knee such as a teacup sitting in a saucer is called the MENISCUS. Greek, meniskos= crescent
Each meniscus has a outside peripheral third RED zone which is vascular like your skin perfused with arteries, veins, and pain fibers but then tapering to the inside two thirds central WHITE zone which has no blood being avascular like a fingernail therefore poor healing potential.
Daily we apply forces that shear, stress, and torque our meniscus which can generate enough forces to cause injury with different types and patterns of meniscal injury tears.
As discussed earlier each meniscus has a peripheral third vascular RED zone therefore sewing with zone specific placement of vertical mattress sutures which capsure the very strong radial fibers. These vertical mattress sutures hold with better purchase the meniscal substance to the meniscal rim then horizontal mattress sutures.
A repair is truly sewing the torn meniscus back to its original anatomical position with high expectations of healing since it is in the red peripheral vascular zone.
Removal or trimming torn pieces of a meniscus in its white avascular thin zone does decrease the dispersal of weight function of a meniscus.
Therefore with removal of meniscus substance, there is decreased dispersal of weight function of the menicus. Loss of meniscal substance results in progressuve stress to the articular cartilage of that compartment depending on the percentage of excised meniscus. Loss of meniscus substance is more tolerated in the medial compartment than the lateral compartment due to its geometery.
The lateral compartment has convexly of the lateral femoral condyle and convexly of the lateral tibial plateau therefore more focused stress with weightbearing.