Lumbar Erector Spinae Plane Block: Cadaveric Study

Erector spinae plane block (ESP block) was first described by Forero et al for the treatment of neuropathic chest pain. Total hip arthroplasty is a surgery with a high potential for severe postoperative pain, and greater attention should be paid to postoperative analgesia. There are multiple forms of postoperative analgesia for total hip arthroplasty, such as subarachnoid morphine, femoral nerve block, obturator and lateral femoral cutaneous block, lumbar plexus block, continuous epidural block, and "3 in 1" block, for example. ESP (LESP) block has emerged based on the same principle as the ESP block in the thoracic region. So far, to the best of our knowledge, there are only a few case reports that evidence its use for hip surgery analgesia. This study aimed to study the local anesthetic dispersion and the mechanism of action of the blockade. An experimental, analytical and prospective study will be carried out in which eight fresh adult human cadavers will be selected and injected with 20 ml of 0.01% methylene blue solution at L4 level. The injection will be performed with a Quincke 20G 100-150mm ultrasound-guided needle with a low-frequency curvilinear transducer (4-8 MHz - SonoSite) in the plane between the transverse process of L4 and the spinal erector muscle, bilaterally in each cadaver. by the same operator. After injection of the solution, the cadavers will be submitted to posterior lumbar region dissection by an anatomist and analyzed the dispersion and impregnation of the blue solution.