Influence of burst TENS stimulation on the healing of Achilles tendon suture in man.

Retrograde or antidromic stimulation of the nociceptive C fibres is known to lead to the release of sensory neuropeptides Substance P (SP) and Calcitonin Gene-Related Peptide (CGRP) by the peripheral endings of these ultra-thin nerve fibres. These neuropeptides have, among others, a vasodilatory effect, which explains why they play a role in the healing of soft tissues. Burst TENS (Transcutaneous Electric Nerve Stimulation) is known to be most effective in influencing C fibre-evoked activity. This is why burst TENS was used in a randomised study as a stimulus for the healing of the sutured Achilles tendon in 10 patients, versus 10 others who received no stimulus. There was one drop-out in each group, so that 2 x 9 patients remained available for the study. A needle biopsy, performed after six weeks, showed no significant influence of burst TENS on the histological healing stage, as compared with a rat study. However, a semi-quantitative evaluation of the number of fibroblasts showed a significant advantage for the stimulated group: p = 0.007. This means that burst TENS might influence healing of Achilles tendon sutures in man. But above all, it means that a histochemical study of the influence of burst TENS on the release of substance P and CGRP, after suture of the Achilles tendon in man, would be worthwhile.