Efficacy and safety of a thermosensitive poloxamer-based hydrogel as an anti-adhesive agent in full-endoscopic spine surgery: a randomized controlled trial in Thailand.

Abstract

Randomized controlled trial. This trial aimed to evaluate the efficacy and safety of a thermosensitive poloxamer-based anti-adhesive hydrogel in patients undergoing full-endoscopic lumbar discectomy for lumbar disc herniation. Epidural fibrosis is a complication following lumbar discectomy that is characterized by frequent pain generation. Although full-endoscopic discectomy causes minimal tissue trauma, fibrosis remains a cause of unsatisfactory outcomes. Although thermosensitive poloxamer-based anti-adhesive hydrogels have demonstrated anti-adhesive effects in animal models, clinical evidence for the same remains scarce. A single-center randomized controlled trial was conducted on 71 patients undergoing full-endoscopic interlaminar lumbar discectomy. Patients were randomized to receive either an anti-adhesive agent or methylprednisolone. The primary outcome was leg pain measured using the Visual Analog Scale (VAS)-leg 3 months after surgery. Secondary outcomes included VAS-back and the Oswestry Disability Index (ODI), assessed before and 1, 3, 6, and 12 months after surgery. Epidural fibrosis was graded based on magnetic resonance imaging (MRI) 3 months after surgery. Baseline characteristics were comparable between the groups. Both groups demonstrated significant improvements in VAS and ODI scores from baseline at all timepoints (p <0.001). At 12 months, mean VAS-leg decreased by -5.91 and -5.92 in the antiadhesive and control group, respectively (p =0.995). The antiadhesive and control group showed a -2.17 and -2.06 decrease in VAS-back and -15.13 and -15.15 decrease in the ODI, respectively, with no significant differences between the groups. Extensive epidural fibrosis (grades 3-4) was observed in 8.7% and 32% of the antiadhesive and control group, respectively (p =0.047). Adverse events were rare and comparable. No significant differences in the primary outcome (VAS-leg) at 3 months or in other patient-reported outcomes at 12 months were observed between the groups. MRI 3 months after surgery showed that the thermosensitive poloxamer-based hydrogel reduced extensive epidural fibrosis, although this radiographic benefit did not translate into superior clinical outcomes.