Use of an ultrasonic blade facilitates muscle repair after incision injury

Background: The ultrasonic Harmonic Blade cuts and coagulates soft tissue at temperatures lower than conventional electrosurgery. This study investigated whether improved hemostatic control and reduced collateral damage in skeletal muscle incisions translates into improved myofiber regeneration, reduced fibrosis and faster muscle recovery.

Materials and methods: Transections in the left gastrocnemius muscles of mice were made with the Harmonic Blade, and contralaterally, with either cold steel scissors or electrosurgery. Histology up to 8 wk after surgery was performed to evaluate myofiber regeneration and fibrosis. Tissue inflammation (Gr1+ neutrophils) and vascularization (CD31+ capillaries) were assessed immunohistochemically at 1 wk .

Results: Overall the Harmonic Blade showed significantly higher level of muscle regeneration than cold steel. Fibrosis for both the Harmonic Blade and cold steel decreased three-fold over the 8 wk period, while electrosurgery yielded significantly increasing fibrosis through wk 4 before declining. At 1 wk post-surgery the Harmonic Blade induced less inflammation than electrosurgery, and higher vascularization than electrosurgery and cold steel.

Conclusions: Harmonic Blade-incised tissue showed accelerated vascularization, slight reduction of inflammation, enhanced muscle regeneration and decreased scarring, demonstrating a more effective healing process than electrosurgery.