Intervertebral Disc Disorders With Radiculopathy, Lumbar Region

This study aims to analyze the efficacy and safety of different kinds of steroid injections for back pain, comparing different steroids, dosages, locations (epidural, facet joints, nerve blocks), and also the difference between injections with steroids and local anesthetics, to optimize this treatment that is currently not standardized. The investigators will compare retrospectively and prospectively the efficacy of different injections in the same patients, using mainly a parameter called integral of pain relief, which combines the percentage of pain relief provided by a treatment and its duration over time, as well as improvements in functionality.