Effects of conventional and acupuncture-like transcutaneous electrical nerve stimulation on osteoarthritis of the knee

Abstract

Background: Transcutaneous electrical nerve stimulation (TENS) is one of the most widely used physical modalities for the management of osteoarthritis (OA) knee and various stimulation parameters have been adopted with varying stimulation frequencies. However, the optimal stimulation frequency of TENS in the management of OA knee pain appeared not to have been well studied. Aim: The purpose of this study is to find out, which among conventional TENS (ConTENS) and acupuncture-like TENS (AcuTENS) is more effective for treating knee OA. Materials and Methods: Twenty-four patients with knee OA were randomly allocated to three groups. ConTENS AcuTENS and Placebo TENS (PlaTENS). Participants in the ConTENS and AcuTENS group received TENS treatment with current intensity and frequency based on their group allocation at selected acupuncture points (acupoints) for knee pain; the Pla-TENS participants received intervention, which was identical to the ConTENS treatment group, but the circuit was disconnected. Participants in the three groups were also treated with soft tissue manipulation around the knee joint. Each group received treatment 3 times a week for 3 weeks during the study. Outcome measures were pain intensity measured with numeric pain rating scale (NPRS), goniometric assessment of knee active range of motion and knee functional mobility measured with timed up and go test. Data were collected prior to intervention, at weekly basis during intervention and at 4 weeks follow-up assessment. Results: The ConTENS and AcuTENS reported lower pain intensity scores and increase in the knee active range of flexion than the PlaTENS group at the end of 3 weeks of treatment and at follow-up assessments. However, only the AcuTENS group recorded statistically significant lower pain intensity and improvement in knee flexion than other groups (P < 0.005). Conclusion: AcuTENS treatment was more effective than ConTENS in pain relief and increasing active range of knee flexion for patients with OA of the knee