Research Suggests Improvements in Pain and Physical Function
Knee osteoarthritis is a progressive joint condition that can cause pain, stiffness, swelling, and reduced mobility.
As symptoms worsen, activities such as walking, climbing stairs, getting out of a chair, or standing for extended periods may become increasingly difficult. Although medications, injections, exercise, physical therapy, and surgery may be appropriate for some patients, researchers are also exploring non-invasive therapies that may help manage symptoms.
Interferential current therapy is one such option.
Understanding Interferential Current Therapy
Interferential current therapy uses electrical currents delivered through electrodes placed around the painful area.
Two medium-frequency currents cross within the tissues, producing an interferential therapeutic current. This stimulation may influence pain signaling and may help patients participate more comfortably in movement and rehabilitation.
Because the treatment is delivered through the skin, it does not involve needles, injections, or surgical procedures.
What Did the Meta-Analysis Examine?
A 2022 systematic review and meta-analysis evaluated interferential current therapy in patients with knee osteoarthritis.
The researchers included 10 randomized controlled trials published between 1985 and 2021. Together, the studies involved 493 patients, including 262 who received interferential current therapy and 231 participants in comparison groups.
Across the included trials, researchers evaluated changes in pain and physical function.
Improvements in Pain
The meta-analysis found that interferential current therapy was associated with reduced pain in patients with knee osteoarthritis.
Pain relief is particularly important for osteoarthritis patients because persistent discomfort can discourage movement. Over time, avoiding activity may contribute to muscle weakness, stiffness, and further loss of function.
Reducing pain may make it easier for some patients to remain active and participate in appropriate exercise or rehabilitation.
Improvements in Physical Function
The analysis also found improvements in physical function.
Physical function may include a patient’s ability to:
- Walk comfortably
- Climb stairs
- Bend or straighten the knee
- Stand from a seated position
- Complete daily activities
- Participate in strengthening exercises
These functional improvements are meaningful because the goal of osteoarthritis care is not simply to lower a pain score. It is also to help patients remain mobile and independent.
What About Safety?
The review reported no significant treatment-related adverse effects across the included studies. This suggests that interferential current therapy was generally well tolerated within the research settings examined.
However, electrical stimulation is not appropriate for every patient. Medical history, implanted electronic devices, skin condition, sensation, circulation, and other health factors should be reviewed before treatment begins.
Important Research Limitations
Although the findings were encouraging, the researchers noted differences among the included studies, including variations in treatment settings, session schedules, comparison groups, and interferential current parameters.
Later individual trials have also produced mixed findings. For example, a 2024 trial found that adding interferential current to an exercise program did not improve pain or function beyond the results achieved with exercise alone in patients with mild-to-moderate knee osteoarthritis.
This highlights an important point: interferential current therapy may help some patients, but it should not be presented as a universally effective or stand-alone solution.
What This Research Means for Patients
The available evidence suggests that interferential current therapy may help reduce pain and improve physical function in some patients with knee osteoarthritis.
It may be particularly useful as part of a personalized plan that also considers movement, strength, mobility, body weight, activity tolerance, and the patient’s broader health needs.
Research takeaway: A meta-analysis of randomized controlled trials found that interferential current therapy may improve pain and physical function in patients with knee osteoarthritis and was generally well tolerated. Results may vary, and additional high-quality research is still needed.