Efficacy of diadynamic currents as an adjunct to exercise to manage symptoms of knee osteoarthritis in adults: A randomized controlled clinical trial.

OBJECTIVE: To investigate the effect of diadynamic currents administered prior to exercises on pain and disability in patients with osteoarthritis of the knee.

DESIGN: A randomized-controlled trial.

SETTING: Special Rehabilitation Services in Taboão da Serra.

PARTICIPANTS: Patients with bilateral knee osteoarthritis.

INTERVENTION: Participants were randomly allocated to Group I (diadynamic currents and exercises; n = 30, 60 knees) or Group II (exercises alone; n = 30, 60 knees) and were treated three times a week for 8 weeks.

MAIN OUTCOME MEASURES: The primary outcome measures were change in knee pain evaluated by visual analog scale and disability Index Score (Lequesne). Secondary outcomes included change in mobility (Timed Up and Go test), range of motion (goniometer), muscle strength (dynamometer), a composite score for pain and disability (Western Ontario and McMaster Universities Osteoarthritis questionnaire), and a drug diary to measure consumption of rescue pain medication (paracetamol). All measurements were collected at baseline, 8 weeks, and 6 months from baseline (follow-up).

RESULTS: There were 60 participants with a mean (SD) age of 63.40 (8.20) years. Between-group differences in the follow-up (8 weeks and 6 months) were observed for pain at rest, pain during activities of daily living and disability. There was improvement in Group I that was maintained for the three variables 6 months after treatment. Mean difference for pain at rest was -3.08 points (95% confidence interval -4.13; -2.02), p  < 0.01 with an effect size of 1.4; mean difference for pain during activities of daily living was -2.40 points (95% confidence interval -3.34; -1.45), p  < 0.01 with an effect size of 1.24; and mean difference for disability was -4.08 points (95% confidence interval -5.89; -2.26), p  < 0.01 with an effect size of 1.04.

CONCLUSION: Patients with symptomatic knee osteoarthritis receiving 8 weeks of treatment with diadynamic currents as an adjunct to a program of exercises had significantly greater improvements in pain and disability than those receiving exercises alone. Beneficial effects were sustained for 6 months.