But transcutaneous electrical nerve stimulation (TENS) edged out interferential current therapy (IFT) on several measures.
Up to two-thirds of people with multiple sclerosis (MS) worldwide have chronic pain. People with MS experience painful cramps and muscle spasms. Nerve damage caused by the disease can lead to neuropathic pain.
Treatment for pain associated with MS has included pharmacological and nonpharmacological measures. Electrotherapy, which includes interferential current therapy (IFT) and transcutaneous electrical nerve stimulation (TENS), is commonly used as a non-pharmacological approach to pain management in MS.
(Interferential current therapy is sometimes called IFC therapy. IFT and IFC therapy are the same thing.)
Both IFT and TENS deliver electrical currents to the skin, which stimulates nerve cells that block the transmission of pain signals. The difference between the two is that IFT delivers higher frequency currents that penetrate deeper into the tissue.
Although both IFT and TENS are regarded as effective treatments for pain, IFT has not been directly studied in patients with MS, and there is limited research that has compared IFT with TENS
A small study published this month in Multiple Sclerosis and Related Disorders compared the effects of IFC and TENS on pain, functional capacity and quality of life in patients with MS. The study, led by Zekiye İpek Katirci Kirmaci from Kahramanmaraş Sutçu Imam University in Turkey, included 30 adult patients with relapsing-remitting MS who experienced pain. The participants were randomized to receive either IFC or TENS for 30 minutes per day, 5 days per week, for a total of 4 weeks.
Pain severity was assessed before and after the intervention using the Visual Analogue Scale (VAS) and the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) pain scales. Physical function was measured with the 2-Minute Walk Test (2MWT), and quality of life was evaluated using the Multiple Sclerosis International Quality of Life (MusiQol) questionnaire.
Results showed that both groups had significantly lower VAS and LANSS scores and a significant increase in 2MWT scores after electrotherapy. Total scores on the MusiQol improved significantly in both groups. But the group that received TENS has improvements in more fields than the IFT group. For example, the TENS group saw significant improvements in the impact of symptoms and the ability to cope with the disease. The IFT group showed no significant improvement in these fields.
The researchers conclude that IFT and TENS alleviate pain and improve physical function in patients with MS. However, TENS is more effective in improving quality of life. They noted that limitations of the study include the small sample size and the absence of a placebo group. They recommend further placebo-controlled research to determine the effectiveness of IFT and TENS in managing MS-related pain.