Ultrasound-guided sub-multifidus block for postoperative pain after lumbar spine surgery - a prospective case series.

We describe this series of 15 cases who were scheduled for single level lumbar spine decompression with instrumentation. Here we describe ultrasound (US) guided sub-multifidus block (SMFB). Injections of local anesthetic deep to the multifidus muscle provided reliable block of dorsal rami of spinal nerves at multiple levels in this series. With US the multifidus muscle can be identified both in axial and parasagittal planes. Needle tip is easily visualized beneath the multifidus and medial to transverse process. A good quality analgesia was documented by pain scores. There were no adverse events. This block needs to be compared with routine multimodal analgesia or with the recently describe thoracolumbar interfascial plane block to compare safety and analgesic efficacy.