The body looks at this as toxic and if it gets absorbed, the liver deals with it mostly as a toxin rather than a nutrient. Eating the chalk will put a large quantity of this material in your body and is not a good idea at all.
This operation can be done either through the same incision as the medial patellofemoral ligament reconstruction or through a larger incision around the knee. It allows the patella to sit more centrally within its groove and not tilt as the patella engages in the trochlear groove.
The patella normally lies within the patellofemoral groove and is only designed to slide vertically within it. Dislocation of the patella occurs when the patella moves or is moved to the outside of this groove and onto the bony head of the femur (lateral femoral condyle). The patella may also sublux rather than fully dislocate, meaning it moves partially out of position. A patella dislocation is not the same as a dislocation of the knee joint itself which is a much more severe traumatic injury. It is usually a result of an acute blow or twisting action of the knee.