Comparing the effects of iontophoresis and phonophoresis of dexamethasone on the treatment of carpal tunnel syndrome

Using anti-inflammatory medicine injection such as dexamethasone acetate (DXA) is a common treatment for carpal tunnel syndrome (CTS). Iontophoresis and phonophoresis of DXA are two other ways which may help to introduce DXA locally to inflammated tissues. This study has been deigned to compare the effect of iontophoresis and phonophoresis of DXA on the CTS treatment. 35 mild or moderate CTS patients (51 affected hands) were randomly assigned in one of the two experimental: iontophoresis (25 affected hands) and phonophoresis (26 affected hands) groups. Subjects in iontophoresis group received 10 sessions of iontophoresis of %0.4 DXA solution (DC, 0.2 mA/cm2, 20 min) over the wrist of the affected hands while the other group received 10 sessions of phonophoresis of %0.4 DXA jell with pulsed ultrasound (1 MHz, 1 W.cm-2, 5 min). The strength of hand and thumb grips, paresthesia, pain, motor and sensory distal latency and evoked potential of median nerve were measured before and after intervention and after 4 weeks follow-up. Comparisons of the mean changes showed more increase in hand grip (P=0.006) and thumb grip (P=0.0002), less pain perception (P=0.001), shorter sensory (P=0.0001) and motor (P=0.0008) distal latency and higher sensory and motor (P=0.0001) action potential in the phonophoresis in compared with the iontophoresis group. Our results show that using phonophoresis of DXA is more effective for CTS treatment, than the iontophoresis method. More studies are needed to investigate the role of different parameters used during phonophoresis of DXA in the CTS treatment.