Inclusion Criteria:  Patients who underwent lower limb surgery and received a single-shot popliteal sciatic nerve block pre-operatively at St. Paul's Hospital from January 4, 2016 to November 1, 2019  Exclusion Criteria:  Patients who had uncontrolled pain (defined as NRS greater than 3 and/or nursing note documentation of uncontrolled or severe pain and/or undocumented pain status) in the post anesthesia care unit (post-operatively) Patients who received a popliteal sciatic nerve catheter