Bone and knee tissue graft for ACL surgery

For anterior cruciate ligament (ACL) surgery, the replacement graft can be harvested from tissue in the patellar (kneecap) region. The surgeon removes the tissue along with a small piece of bone called a "bone block" at each end. The graft is first pulled through the two tunnels that were drilled in the upper and lower leg bones and then secured with screws or staples.