This is the protocol of a randomized controlled trial comparing two methods of treatment for chronic low back pain caused by active discopathy (Type 1 Modic changes).[1] The study will include 118 patients who will be randomized to receive either transforaminal intradiscal steroid injection (TISI) or transforaminal epidural steroid injection (TESI).[1] The primary objective is to measure the change in the intensity of low back pain within one month after the procedure using a numerical rating scale.[1] Secondary outcomes will follow patients for up to 12 months and will include functional status, quality of life, psychological status and radiological changes.[1] The study is single-center, prospective, and blinded so that evaluators and patients do not know which treatment they received.[1] The researchers expect that a head-to-head comparison of these two mechanistically different injection therapies will fill an important gap in medical knowledge and help develop better treatments for this group of patients.[1]