[The effect of electromagnetic fields on tendinopathies : Study on the effect analysis of a singular application of high-energy pulsed electromagnetic fields]

Objective:
Tendinopathies are diseases that often entail long-term treatment consisting of analgesics, physiotherapy, orthotics, and sparing. The aim of this study was to investigate the effect of a single application of a high-energy PEMF (pulsed electromagnetic field) on pain perception and blood born inflammation parameters.

Methods:
34 patients were randomly assigned to a verum group (10 min PEMF, 0,78 T) or a placebo group (10 min sham condition). Prior to and up to one week after the patient blinded treatment (t1-t5), local pain state was assessed by means of algometry as pain pressure threshold (PPT). Accordingly, heat-shock protein 70 (HSP70) levels were analysed. Statistical analyses included 2‑way ANOVA (2 × 5). The clinical trial was registered (DRKS00031321).

Results:
After randomization and drop-out (verum n = 17, placebo n = 13) baseline-analyses did not reveal significant between-group differences for PPT (p = 0,096), for HSP70 (p = 0,524), or any other sample characteristics (p > 0,05). Pain reduction during one week of observation showed to be significantly higher (p = 0,045, η2 = 0,013) for the PEMF group (PPT: +83 bis +139%) compared to the placebo group (PPT: +10 bis +36%). There were no HSP70 associated effects.

Conclusions:
A single bout of high energy PEMF led to an immediate pain relief in tendinopathy patients lasting at least for one week, but the hypothesized underlying HSP70 associated inflammatory pathway could not be confirmed.

Keywords: HSP70; Magnetic field therapy; Pain; Pain pressure threshold; Tendinopathy.

PMID: 39172175 DOI: 10.1007/s00132-024-04541-3