An ultrasound-guided percutaneous electrical nerve stimulation regimen devised using finite element modeling promotes functional recovery after median nerve transection

Percutaneous electrical nerve stimulation of an injured nerve can promote and accelerate peripheral nerve regeneration and improve function. When performing acupuncture and moxibustion, locating the injured nerve using ultrasound before percutaneous nerve stimulation can help prevent further injury to an already injured nerve. However, stimulation parameters have not been standardized. In this study, we constructed a multi-layer human forearm model using finite element modeling. Taking current density and activated function as optimization indicators, the optimal percutaneous nerve stimulation parameters were established. The optimal parameters were parallel placement located 3 cm apart with the injury site at the midpoint between the needles. To validate the efficacy of this regimen, we performed a randomized controlled trial in 23 patients with median nerve transection who underwent neurorrhaphy. Patients who received conventional rehabilitation combined with percutaneous electrical nerve stimulation experienced greater improvement in sensory function, motor function, and grip strength than those who received conventional rehabilitation combined with transcutaneous electrical nerve stimulation. These findings suggest that the percutaneous electrical nerve stimulation regimen established in this study can improve global median nerve function in patients with median nerve transection.