Randomized Double-Blind Study to Evaluate the Efficacy of Transcutaneous Pulsed Radiofrequency (PRF) Treatment for Knee Pain

Randomization and Blinding

• Randomization: Participants will be randomly assigned to one of two groups: PRF treatment or sham.
• Blinding: Both participants and investigators will be blinded to the treatment allocation. The device used for PRF treatment will have an identical appearance for both the active and sham groups, but the sham electrode will not deliver active treatment.

Intervention Both groups will receive disposable electrodes on either side of the knee: one skin electrode on the inside and one on the outside of the knee.

• PRF Group: Participants will receive PRF treatment using a specific protocol (e.g., 3 Hz, 5 ms, 15 minutes, 3 sessions with 1 week and 3 weeks interval). The output will be adjusted according to the distance between electrodes in cm. This will be between 0.7A (circumference 23cm) and 1.4A for 38cm (Spring 2, Clinical Guidelines, Table 1)
• Sham Group: Participants will receive a sham treatment using a device identical in appearance but without delivering the actual PRF therapy.

Outcome Measures Primary Outcome • Pain Reduction: Measured using the NRS (numerical rating scale) at baseline, immediately after treatment, and at follow-up intervals (2 weeks, 4 weeks, 8 weeks, 12 weeks).