Pulsed short wave therapy : its clinical use and physiological effects in healthy subjects and osteoarthritic patients

Abstract

PSWT is a commonly used electrotherapy modality and surveys have shown it to be one of the most widely used modalities among physiotherapists in the UK. Nevertheless, the literature supporting its therapeutic effects and explaining its mechanism of actions remains scant, is of poor methodological quality and of minimal clinical value. This research program was set to examine both the nature of use and the efficacy of PSWT. The nature of PSWT use was examined in outpatient clinics using an audit and a nationwide survey. The efficacy of PSWT was examined in two randomised placebo controlled trials; one conducted in a laboratory setting on healthy subjects and the other was a clinical trial on patients with osteoarthritis. Following the same methodology and protocol, the effects of low and high dose of PSWT on skin temperature (SkT), blood volume (BVol), and nerve conduction velocity (NCV) were evaluated against a placebo and a control condition. The findings have revealed the poor documentary skills of physiotherapists, and a state of confusion ~n the clinical decision-making with regard to PSWT dosage. Based on experimentation, it was established that patients react differently from healthy subjects when similar levels of energies are applied. Whilst low dose resulted in non-significant changes in SkT and NCV in healthy subjects, the same dose significantly altered BVol, SkT, and NCV in patients. Placebo effects were found to account for 39% of the patients' response to PSWT treatments. The findings have revealed a discrepancy between evidence and practice that necessitates a reconsideration of the treatment approaches adopted by physiotherapists when using PSWT. The study has also demonstrated the physiological and therapeutic efficacy of PSWT on patients with osteoarthritis, and showed that treatment outcomes are dependent on the amount of exogenous energy applied and the type of tissue treated. The thesis also highlights areas for future research based on the literature reviewed and the experimentation conducted.