Deep heat therapy via microwave diathermy improves knee osteoarthritis symptoms

Study Type: N/A
OE Level of Evidence: N/A
Journal Level of Evidence: N/A
Deep heating therapy via microwave diathermy relieves pain and improves physical function in patients with knee osteoarthritis: a double-blind randomized clinical trial


54 patients with moderate uni- or bilateral knee osteoarthritis were included in this randomized double blind study to compare the effect of deep heat therapy and superficial heat therapy on functional outcomes, joint pain, and joint stiffness.Results assessed over a 12 month period indicated that deep heat therapy provided early improvements in pain and function that were maintained for the 12 month follow-up period. Improvements in WOMAC... Please login to view the rest of this report. Please login to view the rest of this report.
Funding: Non-funded
Conflicts: None disclosed

Why was this study needed now?

Osteoarthritis of the knee is a degenerative condition, with common symptoms of pain, stiffness, and loss of function. Knee arthroplasty procedures have been shown to be successful in the treatment of severe osteoarthritis. However, there currently is no gold standard for the conservative treatment of earlier stages of knee osteoarthritis. Heat therapy has been used extensively, although the most appropriate method of heat therapy remains to be identified.

What was the principal research question?

Is there a difference in outcome between deep heating therapy via microwave diathermy and superficial heat therapy with hot packs, when measured over a 12 months period?
Population: 54 patients (18 years or older) with uni- or bi-lateral knee osteoarthritis (Kellgren-Lawrence grade II-III) and with pain for 3 weeks.
Intervention: Deep heating therapy: Patients received deep heat therapy, administered using the Smarterapia Sigma Hyperthermia System device. Specifications of the device were 434-MHz microwave generator, maximum output power of 100W, and total radiating area of 240cm2. A silicone pad filled with thermostatic deionized water kept at 38 degrees Celcius was applied 2cm above the patella. Sessions were 30 minutes each, and performed 3 times per week for 4 weeks (Mean age: 64.0; n=27)
Comparison: Superficial heat therapy: Patients were treated with superficial heat therapy, described similarly as above, except that the microwave generator was turned off. As in the DHT group, deionized thermostatic water was kept at 38 degrees Celcius (Mean age: 66.3; n=27)
Outcomes: Primary outcome assessment was through the Italian version of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The British Medical Research Council (BMRC) scale was used to assess muscle strength. Pain was evaluated on a visual analog scale (VAS).
Methods: RCT; Double-blind, Single center
Time: Outcomes were assessed at baseline, at the end of intervention (4 weeks), and at 4, 12, and 24 weeks follow-up. WOMAC was additionally follow-up up after 12 months

What were the important findings?

What should I remember most?

How will this affect the care of my patients?

The authors responsible for this critical appraisal and ACE Report indicate no potential conflicts of interest relating to the content in the original publication.