Effect Of Tens + Tdcs On Pain And Mobility In Older Adults With Knee Osteoarthritis

PURPOSE: Pain and mobility deficits are the primary symptoms of knee osteoarthritis (KOA). This study aims to investigate the effects of combined Transcutaneous Electrical Nerve Stimulation (TENS) and transcranial Direct Current Stimulation (tDCS) on pain and mobility in older adults with KOA, compared to TENS alone. METHODS: Twenty-two older adults with KOA were randomly assigned to either the TENS+tDCS group (N = 11, age = 66.2 ± 7.0 years, height = 158.5 ± 6.6 cm, weight = 66.2 ± 9.3 kg) or the TENS group (N = 11, age = 65.2 ± 6.4 years, height = 164.3 ± 9.9 cm, weight = 73.1 ± 16.1 kg). Participants in the TENS+tDCS group received interventions combining TENS and tDCS, while those in the TENS group received TENS with sham-tDCS. Each intervention lasted 20 minutes, and was administered 4 times per week for 6 weeks. TENS was applied to the knee of the affected limb at an intensity corresponding to each participant's sensory threshold. Concurrently, tDCS was performed at an intensity of 2 mA. Pain levels were assessed using the WOMAC pain scores, and mobility was evaluated using the Timed Up and Go (TUG) test at baseline and after the six-week intervention. Data were analyzed using two-way ANOVAs with repeated measures. RESULTS: Significant time×group interactions were observed in both WOMAC pain scores (P = 0.029, η2p = 0.216) and TUG times (P = 0.035, η2p = 0.204). The pain scores decreased in both groups (TENS+tDCS: week 0 = 13.55 ± 4.25, week 7 = 5.00 ± 2.53, P < 0.001, d = 2.44; TENS: week 0 = 15.73 ± 3.52, week 7 = 10.18 ± 2.14, P < 0.001, d = 1.91), with a greater reduction in the TENS+tDCS group. Additionally, the TUG times decreased in the TENS+tDCS group (week 0 = 11.01 ± 2.98 s, week 7 = 8.45 ± 1.97 s, P < 0.001, d = 1.01) but remained unchanged in the TENS group. CONCLUSIONS: The combined intervention of TENS and tDCS significantly reduced pain and improved mobility in older adults with KOA compared to TENS alone.