&lt;b&gt;Effects of therapeutic ultrasound on haematological dynamics and fibrinogen during the inflammatory phase after muscle injury in rats &lt;/b&gt;

Luis Ulisses Signori,Silvio Teixeira Da Costa,Thiago Dipp,Andre De Oliveira Teixeira,Antônio Marcos Vargas Da Silva,Rodrigo Della Méa Plentz

doi:10.4025/actascihealthsci.v36i1.14472

Abstract

This study investigated the effects of ultrasound therapy on haematological dynamics and plasma fibrinogen during the inflammatory phase of muscle injury. Forty-eight male Wistar rats were divided into control group (CG), continuous ultrasound treated group (CTU) and pulsed ultrasound (PTU). Animals were subjected to surgical incision. A transverse lesion was made in the biceps femoris muscle (50%). CTU (1.0 MHz) was applied at 12-hour intervals on the lesion, for three days, with 0.4 W cm -2 and three minutes of duration (six applications in the total). PTU was applied in the pulsed mode 20% (2 ms on/8 ms off), maintaining the other parameters. Fibrinogen, white and red blood cells were analyzed in the 24 th , 48 th and 72 nd hour after the injury. PTU has reduced fibrinogen levels by 20% at the 24 th h and by 30% at the 48 th h (p < 0.001) and haemoglobin reduction at the 72 nd hour (p < 0.001), which had already occurred during the 2 nd collection in the other groups. CTU favoured erythrocyte reduction at the 48 th h (p = 0.003). PTU presented an anti-inflammatory effect due to plasma fibrinogen reduction, and CTU favored haemorrhage due to the reduction of erythrocytes when applied in the first 72 hours after muscle injury.

Highlights

Therapeutic ultrasound, a form of acoustic energy, plays its effect on cells and tissues via both thermal and nonthermal mechanisms (GUFFEY; KNAUST, 1997)
This study examined for 72h the interaction of the continuous and pulsed US effects on plasma fibrinogen levels and on the haematological dynamics of the different types of white cells and red cells concentrations after muscle injury in rats
The erythrocytes had a reduction of approximately 8% (p < 0.007) on the 48thh only for the group treated with continuous therapeutic ultrasound (CTU)

Summary

Introduction

Therapeutic ultrasound, a form of acoustic energy, plays its effect on cells and tissues via both thermal and nonthermal mechanisms (GUFFEY; KNAUST, 1997). Low-intensity ultrasound (US) is used during physical therapy practice. This US varies in frequency (1 to 3 MHz), intensity and dosage (0.1 to 3 W cm-2), application time and type (continuous and pulsed) of wave (BAKER et al, 2001; O’BRIEN JR, 2007). The thermal and/or mechanical therapeutic effects are optimized according to the type of wave (BAKER et al, 2001). They depend on other parameters and on the interaction of these parameters with different biological tissues (BAKER et al, 2001; JOHNS, 2002; RANTANEN et al, 1999)

Methods

Results

Conclusion