RESUMO
OBJECTIVE: To compare the efficacy of therapeutic ultrasound combined with transcutaneous electrical nerve stimulation versus therapeutic ultrasound alone for pain relief and functional improvement in patients with symptomatic knee osteoarthritis. DESIGN: Randomized controlled trial (blinded assessor). SETTING: Outpatient. PARTICIPANTS: A total of 148 ambulatory knee osteoarthritis patients (pain score ⩾ 5/10) were recruited as study participants. INTERVENTIONS: Ultrasound combined with transcutaneous electrical nerve stimulation (study group) or ultrasound (control group). Both groups received treatment in the supine position for 10 minutes per session, for 10 sessions within two weeks. MAIN OUTCOMES: Pain score and gait speed were measured after random allocation and on day 10. Adverse events, global assessment, and patient satisfaction were recorded after treatment. RESULTS: All baseline data were comparable between groups. The mean (SD) pain score at baseline and day 10 was 5.9 (1.3) and 2.7 (1.7) in the control group, and 5.8 (1.3) and 2.9 (1.7) in the study group, respectively. Gait speed at baseline and day 10 was 1.11 (0.30) and 1.23 (0.38) m/s in the control group, and 1.10 (0.36) and 1.17 (0.39) m/s in the study group, respectively. No difference was observed between groups for total pain score (0.28; 95% confidence interval (CI): -0.28, 0.84) or gait speed (-0.03; 95% CI: -0.13, 0.07). The results from intention-to-treat analysis were similar to those from per-protocol analysis. No difference was observed between groups for adverse events. Most participants reported satisfaction and improvement for the global assessment. CONCLUSION: Adding transcutaneous electrical nerve stimulation to ultrasound demonstrated no additional beneficial effect over ultrasound alone in patients with symptomatic knee osteoarthritis.