Utilization of Quadratus Lumborum Versus Lumbar Plexus Blocks for Postoperative Analgesia Following Hip Arthroplasty: A Prospective, Randomized Clinical Trial

With the goal of improving physical function and quality of life, the demand for total hip arthroplasty (THA) continues to grow. However, postoperative pain associated with THA remains a serious concern for patients. In the middle of a growing opioid epidemic, multimodal approaches utilizing both non-opioid analgesics and regional anesthetic techniques are being increasingly sought.

Regional anesthetic techniques are associated with both decreased opioid consumption and pain scores compared with systemic analgesia alone. However, regional techniques for THA are seldom compared. Lumbar plexus blocks are commonly performed for postoperative analgesia for THA. However, more recent case reports have described utilizing quadratus lumborum blocks for analgesia following hip fracture and THA.

This prospective study would randomize subjects to receive a lumbar plexus block or quadratus lumborum block prior to THA. The primary end point would be opioid consumption at 12 hours postoperative. Our hypothesis is that opioid consumption will not differ between groups.

The quadratus lumborum block is a fascial plane block. Originally described for abdominal surgery, numerous case reports and editorial publications have highlighted the effectiveness of quadratus lumborum (QL) blocks as an analgesic technique for hip fracture and hip arthroplasty. However, prospective randomized studies comparing QL blocks to other regional techniques for THA analgesia are lacking.

The lateral approach to the QL block is performed by injecting local anesthetic deep to the transversus abdominus abdominus apnoneurosis and superficial to the fascia transversalis with direct ultrasound guidance. After completing consent, placing monitors and providing mild sedation, the subject is positioned laterally and the muscular anatomy (external oblique, internal oblique, transverse abdominis, quadratus lumborum and latissimus dorsi muscles) identified. After placing a subcutaneous skin wheal with lidiocaine, a blunt regional anesthesia needle is inserted using in-plane ultrasound guidance. Local anesthetic is deposited incrementally with frequent aspiration in the anterolateral border of the quadratus lumborum muscle at the junction of the transversalis fascia, outside the anterior layer of the thoracolumbar fascia and superficial to the fascia transversalis.