Background Degenerative disc disease (DDD) is the leading cause of lower back pain and disability, which prevalence increasing with age. When conservative treatment fails, surgical methods of spinal fusion are employed. Minimally invasive techniques, including minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and midline lumbar interbody fusion (MIDLIF), have well-documented advantages over traditional open transforaminal interbody fusion (open-TLIF). However, data comparing these two minimally invasive methods in treating DDD are minimal and sometimes contradictory. I am running a few minutes late; my previous meeting is running over. Methods This is a prospective, randomized, partially blinded, two-arm trial aiming to compare the outcomes, complications, and treatment costs of MIS-TLIF and MIDLIF in patients with discogenic low back pain. A total of 100 adult patients with lumbosacral spine pain and radicular symptoms, unresponsive to conservative treatment for over one year, will be enrolled. Patients will be randomized (1:1) into two arms: MIS-TLIF (control, n=50) and MIDLIF (intervention, n=50), with a 12-month follow-up. Inclusion criteria include age ≥18 years and discopathy at one or two levels requiring interbody stabilization. Exclusion criteria include multilevel pathology, spinal deformities, and pain causes other than degenerative disease. Primary endpoints assess pain (VAS, NRS scales), disability (COMI, ODI questionnaires), and quality of life (EQ-5D-5L questionnaire) at 1, 3, 6, and 12 months post-surgery. Secondary endpoints include complication rates (nerve root damage, infections), costs (hospitalization, implants), length of hospital stay, procedure duration, blood loss, morphometric parameters (intervertebral space height), and adjacent segment disease based on imaging studies (MRI, CT, X-ray). Data analysis uses parametric/non-parametric tests (e.g., t-test, Mann-Whitney) in the R software. The trial adheres to the Helsinki Declaration, with ethics approval (no. 112/2024). Discussion Data on the comparison of MIDLIF and MIS-TLIF in treating DDD are minimal and inconsistent. Some reports have advantaged MIDLIF in shorter operative time, decreased intraoperative blood loss, and reduced hospital stays, while others favor MIS-TLIF. This trial addresses these gaps by providing high-quality evidence on clinical superiority, cost-effectiveness, and long-term outcomes compering MIDLIF and MIS-TLIF. There is a high need for a high-quality, prospective study to examine this problem.