A retrospective assessment of the effectiveness of pulsed radiofrequency ablation in the treatment of chronic pain caused by advanced knee osteoarthritis.

Introduction: Patients suffering from severe chronic pain often have problems finding an appropriate combination of painkillers. We retrospectively evaluated the effectiveness and safety of pulsed radiofrequency ablation (pRFA) of the genicular nerves in 96 patients with knee osteoarthritis (KO). We hypothesized that age, sex, and body mass index (BMI) may influence the quality of the pRFA treatment.

Material and methods: A diagnostic blockade with total volume of 9 ml of 1% lidocaine (WZF, Poland) combined with 4 mg of dexamethasone with subsequent pRFA with a radio frequency of 300-500 kHz under ultrasound guidance was used during the procedure. The study participants were assessed during regular monthly visits until 12 months.

Results: The nerves' ultrasound identification was successful in 90.62% of the cases. According to the numeric rating scale (NRS), pain was reduced by 50% or more in 64.06% of the cases. The average pain relief period lasted just over 7 and a half months. There were no pRFA-related complications or side effects of the drugs used.

Conclusions: pRFA seems to be safe and effective for the treatment of chronic pain in KO. The outcome of the treatment may be related to the patient's age (block duration increased with patient age) and sex (in women, the therapeutic effect was more effectively prolonged) in our study group. There was also higher effectiveness of pRFA in high-BMI patients, which was close to statistical significance ( P = 0.053).