The aim of this study is to observe or not a reduction in the consumption of morphine within 72 hours of the realization of an erector spinae plane block when preparing for a lumbar spinal fusion.

Posterior lumbar spine surgery is surgery described by patients as painful. For this type of surgery, lumbar spinal fusion, especially because of greater exposure, is more painful than simple surgeries to release the lumbar canal or to cure a herniated disc. However, the improvement of implants and techniques, as well as the change in the habits of surgeons, means that this lumbar spinal is on the increase (+ 65%). The management of postoperative pain is a priority for anesthesiologic teams with a goal to improved rehabilitation after surgery.

Multimodal analgesia, already recognized for other surgeries, is one of the keys to success, combining oral analgesics and regional local anesthetics.

The recourse to the realization of a erector spinae plane block was described for the first time in 2016, it is described as not presenting any particular risk, simple to apply and having a satisfactory analgesia action. However, this process is little described in the context of spine surgery and even less in the context of randomized controlled trials. On the other hand, no study has evaluated the effectiveness of spinal block as part of an Enhanced Rehabilitation After Surgery (RAAC) program.

At the Clinique Saint Jean Sud de France, the management of spine surgeries is part of an Improved Rehabilitation After Surgery (RAAC) process. Patients benefit from multidisciplinary preoperative information and perioperative management promoting early mobilization and postoperative rehabilitation.

It seemed relevant to carry out a randomized, controlled, double-blind study to evaluate the consumption of postoperative morphine during the 72 hours following a lumbar spinal fusion.

The studied process will be the realization of a ultrasound guided erector spinae plane block.

The realization of the erector spinae plane block is carried out as part of lumbar spinal fusion surgery on 1 or 2 levels.

As part of this study, 130 patients will be randomized into 2 arms: one arm receiving the anesthetic and another arm receiving the placebo. As the study is double blind, both arms will benefit from the same procedure. Patients in the block arm will receive an injection of levobupivacaine 2.5 mg / ml while the patients in the placebo arm will receive an injection of physiological saline (NaCL 0,9%) in the same proportions.

The data necessary for this study will be collected directly from the patient and from his medical file according to the following schedule: 3h, 4h, 6h, 9h, 12h, 18h, 24h, 36h, 48h, 72h and 1 month after realization of the erector spinae plane block.

Inclusion Criteria:

• Patient with medical insurance.
• Patient who received information about study and signes a consent to participate in the study.
• Major patient requiring a lumbar spinal fusion surgery.
• Patient with an ASA score of 1, 2 or 3.

Exclusion Criteria:

• Minor patient.
• Patient with morphine intolerance
• Patient with allergy to local anesthetics.
• Patient consuming morphine for more than 3 months.
• Pregnant or breastfeeding patient.
• Patient scheduled for cancer surgery or trauma surgery.
• Patient participating in another interventional study.
• Patient with history of lumbar spinal fusion.
• Patient requiring lumbar surgery without arthrodesis.
• Patient requiring lumbar surgery with inter-lamar or inter-epineal stabilization.
• Patient refusing to sign the consent form.
• Patient for whom it is impossible to give informed information.
• Patient under the protection of justice, under curatorship or under tutorship.