Influence of electrode placement on effective field strength in the superficial digital flexor tendon of horses.
OBJECTIVE
To determine the relationship between the output of an electrical treatment device and the effective field strength in the superficial digital flexor tendon of horses.


METHODS
Cadaver horse forelimbs without visible defects (n = 8) and 1 live pony.


METHODS
Microcurrents were generated by a microcurrent electrical therapy device and applied in proximodistal, dorsopalmar, and mediolateral directions in the entire forelimbs, dissected tendons, and the pony with various output settings. Corresponding field strengths in the tendons were measured.


RESULTS
A linear relationship was detected between current and field strength in all conditions and in all 3 directions. In dissected tendons, significant differences were detected among all 3 directions, with highest field strength in the proximodistal direction and lowest in the dorsopalmar direction. In the entire forelimbs, field strength in the proximodistal direction was significantly lower than in the mediolateral direction. Results in the pony were similar to those in the entire forelimbs.


CONCLUSIONS
Electrode placement significantly affected field strength in the target tissue. Many surrounding structures caused considerable reduction of field strength in the target tissue. These factors should be taken into account when establishing protocols for electrical current-based therapeutic devices if these devices are proven clinically effective.
Lin
Yi-lo
YL
Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, The Netherlands.
Moolenaar
Hugo
H
van Weeren
P René
PR
van de Lest
Chris H A
CH
D000818:Animals; D002102:Cadaver; D017097:Electric Impedance; D004558:Electric Stimulation; D004566:Electrodes; D005552:Forelimb / Q000033:anatomy & histology / Q000502:physiology*; D006736:Horses / Q000502:physiology*; D013710:Tendons / Q000502:physiology*