Zapping Nerves Didn't Help Knee Arthritis

Knee osteoarthritis patients benefited from health education and exercise but not TENS

(RxWiki News) Exercise can benefit arthritis patients by helping reduce pain, stiffness and disability. Certain electrical devices have been tried for the treatment of arthritis as well, and researchers recently studied whether one such device could add to the benefits of exercise for knee osteoarthritis.

Transcutaneous electrical nerve stimulation (TENS) is the use of an electrical device to stimulate nerves around the knee joint and reduce pain, but the effectiveness of the device is unclear.

A new study showed that TENS failed to provide any additional clinical benefit over exercise and education in knee osteoarthritis patients.

"Ask your doctor about treatment alternatives for osteoarthritis."

This study was conducted by Shea Palmer, PhD, of the Faculty of Health & Life Sciences at the University of the West of England in Bristol, UK, along with colleagues.

The objective of the study was to examine the effect of TENS, when combined with education and exercise, on knee osteoarthritis.

In osteoarthritis, the protective tissue where bones are joined together is damaged, leading to pain and loss of function.

TENS is the use of a mild electric current produced by a device to stimulate nerves to block pain signals. The use of TENS in osteoarthritis has been controversial.

For this study, the researchers looked at 224 osteoarthritis patients, both men and women, with an average age of 61 years. Patients were divided randomly into three groups.

One group (77 patients), called the knee group, received only education and exercise in the form of physical therapy for six weeks. Another group (73 patients), called the TENS and knee group, received TENS along with education and physical therapy for six weeks.

The third group of patients (74 patients) received education and physical therapy for six weeks and were treated with sham TENS devices that looked just like a regular TENS device but produced no active electric current.

The education program aimed to help patients self-manage their condition. It provided information on personal objectives, managing disease complications, medications, exercise options and adherence to an exercise regimen.

After six weeks, the researchers looked at the effect of the treatment using a measurement called the WOMAC scale. The WOMAC scale measures the patient’s condition with regards to pain, stiffness and joint function based on the ability to perform various day-to-day activities.

They also assessed pain, stiffness, muscle strength and change in overall condition using questionnaires.

Though all outcomes improved in six weeks, the researchers found no significant differences between the three groups. The same improvements were observed at 24 weeks.

Overall, the researchers concluded that there were no additional benefits of using TENS therapy.

According to Daniel A. Clearfield, DO, MS, CAQSM, primary care sports physician and Assistant Professor in the Department of Orthopaedic Surgery at the University of North Texas Health Science Center, “TENS has been demonstrated to be beneficial in muscle specific conditions, such as in low back pain with muscular spasm and in muscle strains and tendon injuries.

“In the setting of knee arthritis, the patient needs to work on mobilizing their joint and strengthening the surrounding muscles so that when they put weight on their leg they use the muscles and ligaments to stabilize more so than on the joint directly itself. TENS could help with achieving a more painless range of motion, but would have less direct effects on the knee arthritis,” said Dr. Clearfield.

The results of this study were published in August in Arthritis Care & Research.

The study was funded by Physiotherapy Research Foundation and Above & Beyond Charities. The authors disclosed no conflicts of interest.

Review Date: 
September 8, 2013