Immediate effect of electric point stimulation (TENS) in treating latent upper trapezius trigger points: a double blind randomised placebo-controlled trial.

OBJECTIVE: The purpose of this study was to investigate the immediate effect of electric point stimulation in treating latent upper trapezius trigger points compared to placebo.

DESIGN: Double blind randomised placebo-controlled trial.

SETTING: Anglo-European College of Chiropractic.

PARTICIPANTS: Sixty participants with latent upper trapezius trigger points.

INTERVENTIONS: Electric point stimulator type of TENS, or detuned (inactive) electric point stimulator type of TENS.

MAIN OUTCOME MEASURES: The three outcome measures were pressure pain threshold at the trigger point, a numerical rating scale for pain elicited over the trigger point, and lateral cervical flexion to the side opposite the trigger point.

RESULTS: On the outcome of pressure pain threshold the electric point stimulator group had a mean change of 0.49 (0.99) kg/cm(2), while the placebo group had a mean change of 0.45 (0.98) kg/cm(2) (t = 0.16, df = 58, p = 0.88). For change in pain over the trigger point, the electric point stimulator group had a mean decrease of 0.93 (0.87) points, while the placebo group had a mean decrease of 0.23 (0.97) points (t = 0.70, df = 58, p = 0.005). On the outcome of change in lateral cervical flexion the electric point stimulator group had a mean increase of 2.87 (4.55) degrees, while the placebo group had a mean increase of 1.99 (2.49) degrees (t = 0.92, df = 58, p = 0.36).

CONCLUSION: Electric point stimulator type of TENS is superior to placebo only in reduction of pain for treating latent upper trapezius trigger points.