Prospective Comparative Study of Epiduroscopic Adhesiolysis in Patients With Failed Back Surgery Syndrome and Patients Without Prior Lumbar Surgery

This investigator-initiated prospective, multicenter, randomized, double-blind controlled study was conducted at certified interventional pain centers in Slovakia to evaluate the clinical effectiveness and safety of epiduroscopic adhesiolysis in patients with chronic lumbar radicular pain. The protocol was approved by regional ethics committees, and all participants provided written informed consent. The study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice principles.

Eligible participants were adults with chronic lumbosacral radicular pain persisting for more than six months despite conservative treatment. Patients were enrolled into two predefined clinical cohorts according to surgical history: (1) failed back surgery syndrome (FBSS), defined as persistent or recurrent radicular pain following lumbar spine surgery, and (2) surgery-naïve patients without prior lumbar surgery. Cohort allocation was performed prior to randomization, while all other eligibility criteria were identical across groups.

Within each cohort, participants were randomized in a 1:1 ratio to undergo either epiduroscopic mechanical adhesiolysis alone or mechanical adhesiolysis combined with targeted epidural pharmacologic therapy. Randomization was computer-generated and stratified by study center. The study was double-blinded; patients and outcome assessors were unaware of treatment assignment, while the operating physician did not participate in follow-up evaluations.

All procedures were performed via a sacral epidural approach under fluoroscopic guidance using a flexible epiduroscope. Mechanical adhesiolysis consisted of endoscopic dissection and saline irrigation to release epidural adhesions around symptomatic nerve roots. In the pharmacologic treatment groups, adhesiolysis was followed by epidural administration of methylprednisolone acetate (40 mg), hyaluronidase (1,500 IU), and hypertonic saline (10 mL). In the mechanical-only groups, isotonic saline was administered to maintain blinding. Procedural and perioperative management were standardized across centers.

Clinical assessments were performed at baseline and at 6 months after the procedure. Outcomes included pain intensity measured by the Numeric Rating Scale (NRS), health-related quality of life assessed using EQ-VAS and EQ-5D-5L, functional status, analgesic consumption, and procedure-related adverse events. All evaluations were conducted by blinded assessors.