Prospective, Multicenter, Randomized, Crossover Clinical Trial Comparing the Safety and Effectiveness of Cooled Radiofrequency Ablation With Corticosteroid Injection in the Management of Knee Pain From Osteoarthritis

Abstract

Background and objectives: Osteoarthritis (OA) of the knee affects the aging population and has an associated influence on the health care system. Rigorous studies evaluating radiofrequency ablation for OA-related knee pain are lacking. This study compared long-term clinical safety and effectiveness of cooled radiofrequency ablation (CRFA) with intra-articular steroid (IAS) injection in managing OA-related knee pain.

Methods: This is a prospective, multicenter, randomized trial with 151 subjects with chronic (≥6 months) knee pain that was unresponsive to conservative modalities. Knee pain (Numeric Rating Scale [NRS]), Oxford Knee Score, overall treatment effect (Global Perceived Effect), analgesic drug use, and adverse events were compared between CRFA and IAS cohorts at 1, 3, and 6 months after intervention.

Results: There were no differences in demographics between study groups. At 6 months, the CRFA group had more favorable outcomes in NRS: pain reduction 50% or greater: 74.1% versus 16.2%, P < 0.0001 (25.9% and 83.8% of these study cohorts, respectively, were nonresponders). Mean NRS score reduction was 4.9 ± 2.4 versus 1.3 ± 2.2, P < 0.0001; mean Oxford Knee Score was 35.7 ± 8.8 vs 22.4 ± 8.5, P < 0.0001; mean improved Global Perceived Effect was 91.4% vs 23.9%, P < 0.0001; and mean change in nonopioid medication use was CRFA > IAS (P = 0.02). There were no procedure-related serious adverse events.

Conclusions: This study demonstrates that CRFA is an effective long-term therapeutic option for managing pain and improving physical function and quality of life for patients with painful knee OA when compared with IAS injection.

Clinical trial registration: ClinicalTrials.gov (NCT02343003).

Conflict of interest statement

T.D., M. DePalma, A.B., M. Desai, and L.K. are members of the clinical advisory board for Halyard Health, Inc. The other authors declare no conflict of interest.

Figures

FIGURE 1

A, True anteroposterior image of distal femur with CRF probes (3; at arrows) in place and (B) true lateral image of proximal tibia with probes (3; at arrows) in place.

FIGURE 2

Disposition of study volunteers and study timeline, including follow-up time points for data collection. *Reasons for screen failures: 6 patients failed the diagnostic block entry criterion, 15 presented with grade 1 OA, 3 had evidence of a structural abnormality other than OA that affected their gait, function, and/or pain, 8 withdrew consent during the screening period because of a non-AE reason, 7 failed the OKS requirement, 25 were excluded for multiple reasons, and the remaining 18 patients violated other unique inclusion/exclusion criteria.

FIGURE 3

Numeric Rating Scale—mean usual knee pain. Mean CRFA and IAS study group NRS scores are indicated by bars, and SDs are expressed as whiskers. *P < 0.05 and **P < 0.0001 (Wilcoxon rank sum test) versus IAS means at same time points.

FIGURE 4

Numeric Rating Scale—changes in usual knee pain at 6 months. Changes in CRFA (A) and IAS (B) study group NRS scores from baseline at 6 months are indicated by the horizontal black bars. The treatment “responder” qualification required an NRS score decrease from baseline of 50% or greater.