Impact of Bad Ragaz ring in hot spring water on knee osteoarthritis: A prospective observational study

To evaluate the impact of the Bad Ragaz ring method (BRRM) in hot spring water for knee osteoarthritis (KOA), this prospective study enrolled KOA patients treated at the hospital between March 2020 and December 2020. The primary outcome was the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index score. A total of 60 patients were included, with 30 participants in the BRRM group and 30 patients in the non-BRRM group, respectively. The mean age was 56.4 ± 10.2 years (13 females), and the duration of disease was 5.0 ± 2.2 years in the BRRM group. The mean age was 56.0 ± 11.3 years (14 females), and the disease duration was 4.7 ± 2.1 years in the non-BRRM group. There were no differences between the 2 groups in the pain, stiffness, and function scores of the WOMAC (all P > .05) before treatment. The pre post difference in total WOMAC scores (56.57 ± 12.45 vs 36.81 ± 13.51, Cohen d = 1.52, P < .01) between the 2 groups was statistically significant. Compared with the non-BRRM group, the BRRM group showed lower scores for pain (6.5 ± 1.5 vs 8.1 ± 2.9, Cohen d = -0.69, P = .01), stiffness (2.7 ± 1.0 vs 5.0 ± 1.2, Cohen d = -1.93, P < .01), and function (14.8 ± 6.6 vs 26.7 ± 7.5, Cohen d = -1.68, P < .01) after treatment. In conclusion, the BRRM might improve the pain and function of patients with KOA.