Lumbar Plexus vs Quadratus Lumborum Block in Post-operative Pain Following Total Hip Replacement

The Lumbar Plexus (LP) block is currently used as the standard-of-care regional anesthesia technique to provide postoperative pain management after primary hip replacement surgery at UPMC Shadyside Hospital. However, the LP technique is complex and can be associated with potentially serious side effects, including nerve injury, major bleeding, retroperitoneal hematoma, and intrathecal injection of local anesthetic. In rare instances the LP block can also lead to motor blockade, interfering with early ambulation. There are several case reports of Quadratus Lumborum inter-fascial block (QL3) giving equally adequate pain relief after total hip replacement surgery, and this QL3 block is performed routinely at this institution. The benefits to inter-fascial administration of local anesthetic include the avoidance of theoretical nerve injury, bleeding and intrathecal anesthetic administration associated with the direct interaction between the nerve and the nerve block needle. The purpose of this study is to show that QL3 block is non-inferior to the standard-of-care lumbar plexus block and should be used more regularly in hip replacement surgery. The study will be conducted as a prospective, randomized (1:1), double-blind, non-inferiority, active-comparator trial. The investigators plan to enroll 40 subjects, 20 in each treatment group. This study will prospectively investigate the efficacy of QL3 versus Classic LP block for post-operative pain management in subjects undergoing primary, unilateral hip replacement surgery and prospectively compare QL3 versus Classic LP block in time to mobilization and physical therapy response. Primary outcome measures include pain at rest and with movement at 6, 12 and 24 hours after surgery. Secondary outcomes will be time for first request for pain medication, total pain medications (narcotics and non-narcotic analgesics) given in 24 hours and the time of participant's ability to walk 100 feet as recorded by a physical therapist.