Laser therapy versus pulsed electromagnetic field therapy as treatment modalities for early knee osteoarthritis: a randomized controlled trial

BACKGROUND: This randomized controlled trial aimed to compare the effects of pulsed electromagnetic field therapy (PEMFT) and low-level laser therapy (LLLT) on pain and physical function of participants with knee osteoarthritis (KOA). METHODS: According to the Kellgren–Lawrence classification, participants with grade 2–3 KOA were randomized to receive PEMFT or LLLT for six sessions lasting 15 min/session over a 3-week period. Pain at rest and when walking, standing from a sitting position, and climbing the stairs was assessed using the visual analog scale. Functional level was measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), timed up-and-go test (TUG), and 10-m walk (10 MW) test. Measurements were obtained before and after the interventions. Significance was determined at p ≤ 0.05. RESULTS: Forty participants were included in the study. Pain and physical function improved significantly (p < 0.0001) in both groups. PEMFT was significantly more effective in reducing pain at rest, when standing from a sitting position, and when climbing the stairs, and in improving both WOMAC scores and TUG results (p ≤ 0.0003). The improvements in pain during the activities and the WOMAC scores reached the minimal clinically important difference. No adverse events occurred. CONCLUSION: Six sessions of PEMFT and LLLT had immediate positive effects on pain and physical function in individuals with low-grade KOA, with PEMFT resulting in significantly better results. TRIAL REGISTRATION: ISRCTN registry trial ID: ISRCTN17001174 SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12877-022-03568-5.