Effectiveness of Different Frequencies of Interferential Therapy on Pain and Disability in Individuals with Low Back Pain: A Randomized Controlled Trial Study

Abstract

Objectives: The objective of the study is to compare the effectiveness of quadripolar with bipolar amplitude-modulated frequency (AMF) Interferential therapy (IFT) in reducing pain level and improving functional status in patients with lower back pain (LBP). Material and Methods: This randomized control trial was conducted over 10 months at the physiotherapy outpatient department, Sri Ramachandra Hospital, Chennai. A total of 120 adults with mechanical LBP were randomized into two groups receiving either quadripolar or bipolar AMF IFT, along with standardized exercises for 2 weeks. Pain and disability outcomes were assessed using the numeric pain rating scale and the Oswestry Disability Index. Statistical analysis was performed using paired and independent t -tests with Statistical Package for the Social Sciences v23. Results: Out of 120 participants, 102 completed the study. Both groups produced better pain reduction using IFT and standardized exercises. However, the quadripolar AMF group demonstrated statistically greater improvements ( p < 0.001), exceeding the minimum clinically important difference. Conclusion: Quadripolar AMF IFT, along with exercises, is more effective than bipolar AMF in treating LBP patients over a short-term period. These findings support the clinical relevance of frequency-specific IFT in optimizing physiotherapy protocols for LBP management.