The Role of Peripheral Nerve Electrotherapy in Functional Recovery of Muscle Motor Units in Patients after Incomplete Spinal Cord Injury

Abstract

Functional electrical nerve stimulation (FES) is a non-invasive technique for neuromodulation and may have the potential for motor rehabilitation following incomplete spinal cord injury (iSCI). Axonal degeneration in motor fibers of lower extremity nerves is an inevitable secondary pathological change in iSCI subjects, despite no direct damage to lumbosacral neuromeres. This study evaluated the role of FES with individual parameters based on results of comparative neurophysiological studies. Forty-two participants with C4 to Th12 iSCI received repetitive sessions of electrostimulations applied to peroneal and tibial motor fibers, performed five times a week from 6 to 14 months, and the uniform system of kinesiotherapeutic treatment. The average duration of one electrostimulation session was 17 min, stimulation frequency of a train 20–70 Hz, duration of 2–3 s, intervals 2–3 s, pulses intensity 18–45 mA. The algorithm change was based on objective tests of subsequent surface electromyography (sEMG), and electroneurography (ENG) recordings. The same neurophysiological studies were also performed in patients after C2-Th12 iSCI treated with kinesiotherapy only (K group, N = 25) and compared with patients treated with both kinesiotherapy and electrostimulation (K + E, N = 42). The study revealed improvements in sEMG parameters recorded from tibialis anterior, gastrocnemius, extensor digitorum brevis muscles, and ENG evoked a compound muscle action potential recorded following bilateral stimulation of more peroneal than tibial nerves. Neurophysiological recordings had significantly better parameters in the K + E group of patients after therapy but not in the K group patients. The improvement of the motor transmission peripherally may reflect the specific neuromodulatory effect of FES algorithm evaluated with sEMG and ENG. FES may inhibit degeneration of axons and support functional recovery after iSCI.

Post-Stroke Treatment with Neuromuscular Functional Electrostimulation of Antagonistic Muscles and Kinesiotherapy Evaluated with Electromyography and Clinical Studies in a Two-Month Follow-Up

“…The neuromuscular functional electrical stimulation (NMFES) of antagonistic muscles acting at the wrist and the ankle was applied only to the NMFES+K group. The development of the electrotherapy principles and the details of personally adjusting the stimuli algorithm have been described elsewhere [ 14 , 37 ]. All details regarding the stimulation parameters applied to the NMFES+K group are presented in Table 1 .…”

Relationships between the Clinical Test Results and Neurophysiological Findings in Patients with Thoracic Outlet Syndrome

“…If we consider the contemporary attempts of neurophysiologists to verify the usefulness of nerve conduction studies (usually applied in a brachial plexus injury differential diagnosis) in TOS evaluation, the vast majority of tests have to be performed, as well as needle electromyography recordings, from several muscles of the upper extremity [ 21 , 22 ]. Therefore, the primary goal of our study was to correlate the results of clinical and neurophysiological testing by using especially new and non-invasive methods, such as magnetically-induced and over vertebral motor-evoked potentials at the cervical level or surface electromyography, which have increasingly wider applications in clinical neurophysiology studies [ 31 , 34 , 35 ]. The flow chart of the diagnostic algorithm of the patients proposed in this study was aimed at facilitating the differential diagnosis of TOS, as presented in Figure 3 .…”

“…The sEMG recordings were performed at the base time of 80 ms/D and amplification of 20–1000 µV. The outcome measures were the amplitude parameters both for the healthy volunteer subjects and the patients ( Figure 1 ); the methodological and analysis principles of sEMG have been described elsewhere [ 33 , 34 , 35 ].…”

“…By contrast, the transmission of sensory neural impulses peripherally within the fibres of the cutaneous anterobrachial median nerves, originating from the lower part of the brachial plexus, was expected to express more axonal than demyelinating changes in the SCV recordings following their stimulation at the cubital fossa and recordings along the median aspect of the forearm ( Figure 1 E). More detailed descriptions of hereinabove mentioned ENG studies are provided in the studies by Kothari et al [ 19 ], Huber et al, and Kaczmarek et al [ 35 , 36 ].…”

Electroneurographic Evaluation of Neural Impulse Transmission in Patients after Ischemic Stroke Following Functional Electrical Stimulation of Antagonistic Muscles at Wrist and Ankle in Two-Month Follow-Up

“…Antagonistic muscle groups acting at the wrist and the ankle of patients from the NMFES+K group were stimulated using a personal, mobile, four-channel device (NeuroTrac ® Sports XL, Verity Medical Ltd., Hampshire, UK). The general principles of NMFES were based on the description of a method proposed in the work of Lisinski et al [ 6 ] with modifications developed in Huber et al [ 12 ]. During both sEMG recordings and NMFES, we used the same locations of electrodes covering the location of the motor points of the extensor carpi muscle group versus the flexor carpi muscle group (at the wrist) and the tibialis anterior muscle versus calf muscle group (medial, lateral and soleus muscles at the ankle) ( Figure 4 ).…”