The patella rests in a very groove on top of the femur called the trochlear groove. After you bend and straighten your knee, the patella moves back and forth within this groove. In kneecap replacement surgical treatment, the surgeon helps make an incision inside the front on the knee, after which the http://knee cap replacement https://www.theorthopaedicandpainpractice.com/knee-cap-replacement-understanding-the-basics-of-this-orthopaedic-surgery/