Outpatients scheduled to have ACL surgery typically receive a femoral nerve block to provide analgesia for the front of the knee. Postoperatively, these patients will often report pain in the back of the knee. Local anesthetic infiltration of the posterior aspect of the knee results in blockade of the genicular nerves of the posterior knee. These nerves originate off of the tibial and common peroneal nerves and their blockade will result in improved posterior knee pain relief and may decrease narcotic consumption compared to patients who receive the same infiltration with normal saline.