Thermal and non-thermal effects off capacitive-resistive electric transfer application on the Achilles tendon and musculotendinous junction of the gastrocnemius muscle: a cadaveric study

Background Calf muscle strain and Achilles tendon injuries are common in many sports. For the treatment of muscular and tendinous injuries, one of the newer approaches in sports medicine is capacitive-resistive electric transfer therapy. Our objective was to analyze this in vitro, using invasive temperature measurements in cadaveric specimens. Methods A cross-sectional study designed with five fresh frozen cadavers (10 legs) were included in this study. Four interventions (capacitive and resistive modes; low- and high-power) was performed for 5 min each by a diathermy T-Plus device. Achilles tendon, musculotendinous junction and superficial temperatures were recorded at 1-min intervals and 5 min after treatment. Results With the low-power capacitive protocol, at 5 min, there was a 25.21% increase in superficial temperature, a 17.50% increase in Achilles tendon temperature and an 11.27% increase in musculotendinous junction temperature, with a current flow of 0.039 A +/- 0.02. With the low-power resistive protocol, there was a 1.14% increase in superficial temperature, a 28.13% increase in Achilles tendon temperature and an 11.67% increase in musculotendinous junction temperature at 5 min, with a current flow of 0.063 A +/- 0.02. With the high-power capacitive protocol there was an 88.52% increase in superficial temperature, a 53.35% increase in Achilles tendon temperature and a 39.30% increase in musculotendinous junction temperature at 5 min, with a current flow of 0.095 A +/- 0.03. With the high-power resistive protocol, there was a 21.34% increase in superficial temperature, a 109.70% increase in Achilles tendon temperature and an 81.49% increase in musculotendinous junction temperature at 5 min, with a current flow of 0.120 A +/- 0.03. Conclusion The low-power protocols resulted in only a very slight thermal effect at the Achilles tendon and musculotendinous junction, but current flow was observed. The high-power protocols resulted in a greater temperature increase at the Achilles tendon and musculotendinous junction and a greater current flow than the low-power protocols. The high-power resistive protocol gave the greatest increase in Achilles tendon and musculotendinous junction temperature. Capacitive treatments (low- and high-power) achieved a greater increase in superficial temperature.