Efficacy of Ultrasound-Guided Pulsed Radiofrequency in the Management of Pain Caused by Knee Osteoarthritis: A Systematic Review and Meta-Analysis.

BACKGROUND

Knee osteoarthritis (KOA) is a prevalent degenerative disease that leads to significant disability among elderly individuals. Ultrasound-guided pulsed radiofrequency (UG-PRF) has been shown to be a nonpharmacological, less invasive alternative to other treatment methods for reducing severe chronic joint pain.

OBJECTIVE

To establish whether using UG-PRF to manage KOA pain improves short-term and long-term clinical outcomes for patients with that condition.

STUDY

DESIGN

A systematic review and meta-analysis.

METHODS

Within PubMed, MEDLINE, Embase, and the Cochrane Library, a comprehensive search of relevant studies published from those databases' inception through July 11, 2024, was conducted. Studies assessing the effectiveness of UG-PRF in KOA patients were selected based on predefined inclusion criteria that required the exclusive use of UG for PRF delivery. Data extraction and synthesis utilized a random-effects model to analyze outcomes related to pain reduction and physical function improvement. We used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework to appraise the robustness of the evidence.

RESULTS

A total of 658 records were identified, with 8 studies involving 688 patients included in the meta-analysis. UG-PRF was associated with significant reductions in visual analog scale (VAS) scores at one month (MD = -14.40; 95% CI [-19.61, -9.19]; P < 0.01; GRADE: high), 3 months (MD = -7.83; 95% CI [-10.38, -5.27]; P < 0.01; GRADE: high), 6 months (MD = -5.64; 95% CI [-7.62, -3.66]; P < 0.01; GRADE: high), and 12 months after treatment (MD = -1.08; 95% CI [-1.94, -0.23]; P < 0.01; GRADE: moderate), and those results all exhibited substantial heterogeneity (I² > 90%; P < 0.01). Similarly, secondary outcomes were associated with significant improvements in WOMAC scores at one month (MD = -20.71; 95% CI [-27.43, -13.99]; P < 0.01; GRADE: high) and 3 months after treatment (MD = -22.09; 95% CI [-31.33, -12.84]; P < 0.01; GRADE: high), with high heterogeneity (I² = 77% at one month, 89% at 3 months; P < 0.01). Sensitivity analysis confirmed the robustness of results, except for the VAS at 12 months. Subgroup analysis indicated no significant differences across treatment targets (P > 0.05). Publication bias was suggested for VAS outcomes at one and 6 months, yet fail-safe analysis (N = 86 required to nullify the 12-month effect) and trim-and-fill methods maintained the significance of the findings.

LIMITATIONS: Incomplete reporting of WOMAC scores constrain the robustness of the study's conclusions, particularly as far long-term efficacy as is concerned. Additionally, the current study's limited data on nerve regeneration mechanisms after pulsed radiofrequency ablation (RFA) restricts a comprehensive understanding of the factors that contribute to pain recurrence at the 12-month mark.

CONCLUSIONS

UG-PRF effectively reduces KOA pain and improves function in the short term, with significant benefits observed up to 6 months after treatment. However, the analgesic effects diminish by 12 months, highlighting the need for further research into the long-term efficacy and underlying mechanisms of this technique. The meta-analysis supports the clinical application of UG-PRF as a safe, minimally invasive option for managing KOA pain in adults aged >= 40 years (mean 62.1±9.4 years), though sustained pain relief may require additional interventions.