Tissue heating in different short wave diathermy methods: A systematic review and narrative synthesis

To assess the change in temperature caused by different short wave diathermy (SWD) methods of application in different healthy tissues.

The Cochrane Central Register of Controlled Trials, MEDLINE, Science Direct, CINAHL, SciELO, PEDro, ClinicalTrials.gov, Brazilian Registry of Clinical Trials and the World Health Organization ICTRP were searched (1990-April 2020).

Randomized, quasi-randomized, and single-arm controlled trials assessing temperature change after SWD application in healthy adults were included. Group analysis was done according to SWD mode and where temperature was collected, risk of bias was assessed using the Cochrane tool and the quality of evidence using GRADE. A narrative synthesis was conducted since methodological homogeneity was not sufficient to undertake a meta-analysis.

Eleven studies were included, reporting data of 240 subjects. Regarding skin temperature change, the application that increased temperature the most was under the electrode using continuous SWD on coplanar arrangement of capacitive technique (7.9 [1.76] °C), coplanar arrangement also had the slowest temperature decay, and the lowest temperature found was through a low dose application of pulsed SWD (0.34 [0.69] °C). Regarding muscle temperature change, the application that increased temperature the most was using the inductive technique of pulsed SWD (4.58 [0.87] °C), this technique also had the slowest temperature decay, and the lowest temperature found was through ReBound shortwave diathermy (2.31 [0.87] °C).

SWD efficacy depends on setting choices. This review provides a detailed description of SWD methods of application and a quantitative data set of resulting temperature change.