Comparison of a Cortivazol (ALTIM®) Infiltration of Posterior Epidural Space at L3-L4 Stage Versus an Epidural Infiltration of Cortivazol (ALTIM®) on Contact With Disco Radicular Conflict in Discal Sciatica

In discal sciatica, after failure of medical treatment, the investigators propose frequently a spinal infiltration of corticoids the most closer of disco-radicular conflict. Recently, some cases of paraplegia during lumbar foraminal infiltrations have induce a reduction of indications of this type of infiltration. An alternative would be to propose a lateral epidural infiltration on contact with conflict.The objective of this study is to compare, in 112 patients with a less than 6 months discal sciatica, the efficacy on pain of a non target posterior epidural space infiltration of corticoids done at L3-L4 stage on scan control versus an epidural infiltration of the same corticoid done in lateral on contact of disco radicular conflict on scan control.