Efficacy of Combined High-Intensity Laser Therapy and Collagenase Chemonucleolysis in Lumbar Disc Herniation Management: a Prospective Randomized Controlled Trial.

Introduction: Lumbar disc herniation (LDH) is a prevalent degenerative spinal disorder. While collagenase chemonucleolysis is effective in long-term LDH management, delayed symptom relief remains a limitation. Recent studies suggest that high-intensity laser therapy (HILT) may enhance tissue repair and pain modulation, providing a rationale for exploring its synergistic effects with collagenase therapy. This study aimed to investigate whether combining HILT with collagenase chemonucleolysis could accelerate early postoperative recovery in patients with lumbar disc herniation.

Methods: This single-blind randomized controlled trial was conducted at the Department of Pain Management, The First People's Hospital of Changzhou, between October 2023 and October 2024. This single-center, single-blind randomized controlled trial finally enrolled 60 eligible patients with lumbar disc herniation; participants were randomly assigned to the experimental (HILT + collagenase) or control (collagenase alone) group using a computer-generated randomization sequence with 1:1 allocation. Group assignments were concealed in sealed opaque envelopes until intervention initiation. All participants underwent collagenase chemonucleolysis, with the control group receiving standard postoperative care combined with sham laser therapy, while the experimental group received additional high-intensity laser irradiation alongside conventional treatment. The primary endpoints comprised visual analog scale (VAS) pain scores and clinical efficacy rates evaluated using modified MacNab criteria, while secondary outcomes included the Oswestry Disability Index (ODI), straight-leg-raising angle measurements, and 36-Item Short Form Health Survey (SF-36) quality of life assessments, with standardized evaluations conducted at five predefined intervals: preoperative baseline, 1 week, 1 month, 3 months, and 6 months postoperatively. Statistical analyses were performed using SPSS 20.0. Continuous variables were compared via independent t-tests or Mann-Whitney U tests, while categorical variables were analyzed using chi-squared tests. All tests were two-tailed, with P < 0.05 considered statistically significant.

Results: A total of 60 patients (30 per group) with a mean age of 57.15 ± 9.18 years completed the study. Baseline characteristics including age, gender, body mass index (BMI), herniation level, and symptom duration showed no significant intergroup differences (all P > 0.05). No significant baseline differences were observed between groups regarding age (58.00 ± 7.13 versus 57.06 ± 9.08 years), gender distribution (male: 53.3% versus 50.0%), or disease duration (5.17 ± 3.45 versus 5.73 ± 3.07 months) (all P > 0.05). The results showed that there was no statistically significant difference in baseline data between the two groups of patients. At 1 week and 1 month postoperatively, the experimental group demonstrated significantly better outcomes compared with the control group in terms of pain VAS scores, excellent/good rate, Oswestry Disability Index (ODI) scores, and Short Form 36 (SF-36) quality of life scores (all P < 0.05). However, at 3 and 6 months postoperatively, no significant differences were observed between the two groups. The lack of sustained intergroup differences is supported by small effect sizes (Cohen's d = 0.15 for ODI at 3 months; 95% CI: [-2.74, 0.74]) and overlapping confidence intervals in SF-36 domains, indicating that HILT's therapeutic impact is clinically meaningful only during the early inflammatory phase, with diminishing relevance as collagenase-mediated remodeling dominates long-term recovery.

Conclusions: Our findings demonstrate that high-intensity laser therapy augmentation of collagenase chemonucleolysis significantly improves early postoperative pain and functional outcomes in patients with lumbar disc herniation. However, the therapeutic advantage diminishes by 3 months, suggesting this combination therapy primarily accelerates early recovery rather than altering long-term prognosis.