Chronic lumbar radicular pain is a frequently encountered condition that can cause marked pain, limited physical function, and a substantial decline in quality of life. For patients whose symptoms do not respond adequately to conservative treatment, caudal epidural adhesiolysis is considered a minimally invasive treatment option, particularly when epidural fibrosis or adhesions are thought to contribute to persistent pain.

Even so, treatment response after caudal epidural adhesiolysis is not the same for every patient. Some individuals experience meaningful clinical improvement, whereas others obtain limited benefit. Understanding which factors are associated with a favorable outcome may help clinicians make better treatment decisions and identify patients who are more likely to benefit from the procedure.

In this single-center retrospective cohort study, we reviewed the medical records of patients with chronic lumbar radicular pain who underwent caudal epidural adhesiolysis. The purpose of the study is to evaluate clinical success after the procedure and to explore demographic, clinical, and procedure-related factors that may influence treatment outcomes.

This single-center retrospective cohort study will evaluate the medical records of 40 eligible patients who underwent caudal epidural adhesiolysis at the Mersin University Algology Clinic between March 1, 2023, and January 1, 2026, for chronic lumbar radicular pain or pain related to epidural adhesions. Eligibility will be determined according to the predefined inclusion and exclusion criteria. In patients who underwent more than one procedure during the study period, only the first (index) caudal epidural adhesiolysis will be included in the analysis.

The primary focus of the study is to assess clinical success following caudal epidural adhesiolysis and to examine changes in pain and clinical improvement measures during follow-up. Pain intensity will be assessed using the Numeric Rating Scale (NRS, 0-10), and functional status will be evaluated using the Oswestry Disability Index (ODI) before the procedure and at follow-up visits. Analyses of clinical success and treatment-related change will be based on these outcome measures.

Potential factors associated with treatment outcome will also be examined. These variables will include demographic and clinical characteristics, such as age, sex, symptom duration, diagnosis, history of previous lumbar surgery, baseline pain severity, and prior or concurrent treatments, as well as selected procedure-related variables, including the level to which the catheter was advanced, medications administered during the procedure, and procedure-related complications.

All study data will be collected from the electronic medical record system and patient files. The study is designed to identify factors that may be associated with favorable clinical outcomes after caudal epidural adhesiolysis in patients with chronic lumbar radicular pain and to contribute to improved patient selection in interventional pain practice.

Inclusion Criteria:

• Age 18 years or older
• Underwent caudal epidural adhesiolysis at the Mersin University Faculty of Medicine, Algology Clinic between March 1, 2023, and January 1, 2026
• Evaluated with a diagnosis of chronic lumbar radicular pain or pain related to epidural adhesions
• Availability of pre-procedural clinical data in the medical records
• Availability of procedural technical records in the medical file, including at minimum the procedure date, the level to which the catheter was advanced, and the medications administered and/or procedural details
• Availability of post-procedural follow-up data including Numeric Rating Scale (NRS) and Oswestry Disability Index (ODI) scores

Exclusion Criteria:

• Patients younger than 18 years
• Patients who underwent caudal epidural adhesiolysis outside the period from March 1, 2023, to January 1, 2026, at the Mersin University Faculty of Medicine, Algology Clinic
• Patients without a diagnosis of chronic lumbar radicular pain or pain related to epidural adhesions
• Missing essential pre-procedural clinical data in the medical records
• Insufficient procedural technical documentation in the medical file
• Absence of post-procedural clinical follow-up data
• Missing Numeric Rating Scale (NRS) and Oswestry Disability Index (ODI) scores in the follow-up records

The study population consists of adult patients with chronic lumbar radicular pain or pain related to epidural adhesions who underwent caudal epidural adhesiolysis at the Mersin University Faculty of Medicine, Algology Clinic between March 1, 2023, and January 1, 2026. Only patients who met the predefined inclusion and exclusion criteria and had available pre-procedural, procedural, and post-procedural follow-up data, including Numeric Rating Scale (NRS) and Oswestry Disability Index (ODI) scores, were included in the analysis.

Individual participant data will not be made available because the study is based on retrospectively collected medical record data from a single center, and sharing such data may raise confidentiality and privacy concerns.