Comparison of Quadro Iliac vs Erector Spinae Plane Block on Postoperative Pain and Opioid Use in Lumbar Discectomies

The Quadro Iliac Plane Block (QIPB) will be performed pre-awakening in patients undergoing lumbar vertebra surgeries. Using a low-frequency convex ultrasound transducer (2-6 MHz), the spinal process will be identified at the L3 level in a prone-positioned patient. The transducer will be moved laterally to locate the transverse process within the erector spinae muscle and then rotated to the parasagittal plane to identify the Quadratus Lumborum Muscle (QLM) attachment to the iliac crest. A 22G x 100 mm block needle will be advanced under ultrasound guidance, and 50 mg (0.25%) bupivacaine will be injected bilaterally into the fascia beneath the QLM. This technique is designed to provide effective postoperative pain control by blocking the nerves in the quadratus lumborum plane.

The Erector Spinae Plane Block (ESP) will also be performed pre-awakening. A linear ultrasound probe will be placed transversely at the level of the L3 vertebra to visualize the transverse process. A block needle will be advanced under ultrasound guidance until it touches the transverse process, after which the needle will be withdrawn 1 mm. Fifty milligrams (0.25%) bupivacaine will then be administered bilaterally. The ESP block aims to provide postoperative analgesia by blocking sensory nerves in the erector spinae plane.