Risk factors for residual low back pain at twelve months after low-temperature plasma radiofrequency ablation in lumbar disc herniation: a retrospective cohort study

OBJECTIVES: To investigate the incidence of rLBP and factors independently associated with residual low back pain (rLBP) at 12 months following low-temperature plasma radiofrequency ablation (LTP-RFA) in patients with lumbar disc herniation (LDH). METHODS: This retrospective cohort study included patients with symptomatic LDH who were admitted in Ningbo Medical Center Lihuili Hospital and underwent LTP-RFA between January 2018 and January 2024. Baseline, clinical, and radiological data were collected. Pain and functional outcomes were assessed using the Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopaedic Association (JOA) score. rLBP was defined as the persistence or recurrence of low back pain with a VAS score ≥ 2 for a duration of at least six months after LTP-RFA. Univariate and multivariate logistic regression analyses were performed to identify factors independently associated with rLBP. RESULTS: A total of 281 patients were included. At 12 months, 32.03% (90/281) of patients developed rLBP. Overall, significant improvements were observed in VAS, ODI, and JOA scores after surgery (all P < 0.001). Multivariate analysis identified higher occupational physical workload, advanced disc degeneration (Pfirrmann grade III-IV), and non-central herniation types as factors independently associated with rLBP. Heavy physical labour (OR = 15.951, P < 0.001) and higher Pfirrmann grades (grade IV: OR = 13.086, P < 0.001) were associated with higher odds of rLBP. Compared with central herniation, extreme lateral herniation showed the highest odds (OR = 8.146, P < 0.001). CONCLUSION: rLBP was a common outcome after LTP-RFA. Occupational physical workload, herniation type, and Pfirrmann grade were associated with postoperative rLBP. Preoperative risk stratification and targeted postoperative management may assist in perioperative risk assessment and patient counseling.