Effectiveness and safety of ultrasound-guided needle-knife therapy for patients with spinal pain disorders: a systematic review and meta-analysis

Background Requirements for the development of pre-surgical therapies for spinal pain disorders have arisen, with ultrasound-guided needle-knife therapy (US-NKT) gaining popularity as a minimally invasive treatment. This study aimed to evaluate the clinical outcomes of US-NKT, focusing on its effectiveness and safety. Methods A comprehensive literature survey was conducted by using 12 databases to identify randomized controlled trials (RCTs) comparing the effects of US-NKT with control in patients with spinal pain disorders. Characteristics of RCTs were extracted. Also, a meta-analysis of pain and physical function (PF) outcomes was performed at 1-week, 1-month, and 3-month follow-ups. Adverse events (AEs) were also analyzed. Results Of the 1,694 articles screened, 23 RCTs ( n = 2,107) met the inclusion criteria, with 60.9% addressing spinal degenerative arthropathy. US-NKT significantly reduced pain at 1 week (standardized mean difference SMD: −1.11; 95% confidence interval CI: −1.42 to −0.79; I 2 = 73%) and 1 month (SMD: −1.74; 95% CI: −2.50 to −0.98; I 2 = 95%). However, the effects were not statistically significant at 3 months. PF improved significantly at all time .points, with the strongest effect at 1 week (SMD: −0.92; 95% CI: −1.42 to −0.42; I 2 = 71%). US-NKT demonstrated superior benefits for pain and PF compared with recommended therapies (at all-time points) or conventional NKT (at 1 week and 1 month). AEs were reported in 43.5% of RCTs, with fewer incidents in the US-NKT groups (4.6%) compared with the controls (13.8%). Conclusion US-NKT demonstrates superior efficacy in reducing pain and improving PF compared with recommended therapies or conventional NKT, with a favorable safety profile. However, sustained benefits beyond 3 months remain inconclusive. Systematic review registration https://www.crd.york.ac.uk/prospero/ , identifier CRD42024529315.