Additional effect of transcutaneous electrical nerve stimulation in a therapeutic exercise program for sedentary with chronic neck pain: A double-blind randomized controlled trial.

Objective: To evaluate the additional effect of high frequency (HF) or low frequency (LF) transcutaneous electrical nerve stimulation (TENS) in a specific therapeutic exercise program for the treatment of patients with chronic neck pain.

Methods: A randomized controlled trial. Sixty participants of both sexes and with chronic neck pain were randomized into three groups: therapeutic exercise group + placebo TENS (n = 20), therapeutic exercise group + HF TENS (n = 20) and therapeutic exercise group + low TENS frequency (n = 20). The following assessment instruments were used: Numerical Pain Rating Scale, Neck Disability Index, Pain-Related Catastrophizing Thoughts Scale and Tampa Scale for Kinesiophobia. Participants were evaluated before the interventions, after eight treatment sessions and 1 month after the end of treatment. Primary outcome was disability measured after the eight treatment sessions. Secondary outcomes were pain intensity, catastrophizing, and kinesiophobia after eight treatment sessions and pain intensity 4 weeks after the end of the treatment sessions.

Results: The three groups were similar at baseline for personal and clinical characteristics. Regarding the main study analyses, there were no significant (p > 0.05) or clinical (d < 0.80) differences between the groups for the main variable (disability), nor for the secondary variables (pain intensity, catastrophizing and kinesiophobia).

Conclusions: HF or LF TENS, compared to placebo TENS, does not provide additional clinical benefits to an exercise program for patients with chronic neck pain.