Spinal fracture surgery is a common surgery. Post-operative pain has been reduced by the advent of so-called minimally invasive techniques. The immediate post-operative pain, however, remains relatively high, mainly because of muscle pain following the trauma. The erector spinae plane block (ESPB) is a loco-regional anesthesia technique first described in 2016. A retrospective cohort study showed an improvement in post-operative analgesia of percutaneous osteosynthesis spinal surgery through a reduction in 24-hour morphine use. In order to prove and confirm the effectiveness of this technique, we will conduct a double-blind randomized controlled study. The objective will be to demonstrate the analgesic effectiveness of the technique by reducing morphine consumption in post-operative. The expected reduction in morphine consumption is set at 30%, based on the clinical experience developed in our practice.