Effect of interferential current therapy on pain perception and disability level in subjects with chronic low back pain: a randomized controlled trial.

Objective: To assess the short-term efficacy of transregional interferential current therapy on pain perception and disability level in chronic non-specific low back pain.

Design: A randomized, single-blinded (the assessor collecting the outcome data was blinded), controlled trial.

Setting: A private physiotherapy research clinic.

Subjects: A total of 64 individuals, 20 men and 44 women, mean (SD) age was 51 years (11.93), with low back pain of more than three months, with or without pain radiating to the lower extremities above the knee, were distributed into a control ( n = 20) or an experimental group ( n = 44). A 2:1 randomization ratio was used in favour of the latter.

Interventions: A transregional interferential current electrotherapy protocol was performed for participants in the experimental group, while the control group underwent a 'usual care' treatment (massage, mobilization and soft-tissue techniques). All subjects received up to 10 treatment sessions of 25 minutes over a two-week period, and completed the intervention and follow-up evaluations.

Outcome Measures: Self-perceived pain was assessed with a Visual Analogue Scale. Secondary measure included the Oswestry Low Back Disability Index. Evaluations were collected at baseline and after the intervention protocol.

Results: Significant between-group differences were found for interferential current therapy on pain perception ( p = 0.032) and disability level ( p = 0.002). The observed differences in the between-group mean changes were of 11.34 mm (1.77/20.91) and 13.38 points (4.97/21.78), respectively.

Conclusions: A two-week transregional interferential current treatment has shown significant short-term efficacy, when compared with a 'usual care' protocol, on self-perceived pain and functionality in subjects with chronic low back pain.