Electrical stimulation alters muscle morphological properties in denervated upper limb muscles

Abstract

Background Damage to lower motor neuron causes denervation and degeneration of the muscles affected. Experimental and clinical studies of muscle denervation in lower extremities demonstrated that direct electrical stimulation (ES) of muscle can prevent denervation atrophy and restore contractility. The aim of this study was to identify possible myogenic effect of ES on denervated forearm and hand muscles in persons with spinal cord injury (SCI) and tetraplegia. Methods This prospective interventional study with repeated measurement design included 22 patients aged 48·6 (± 15·7), 0·25 (0·1/46) years after spinal cord lesion, AIS A-D. In each patient, two electrophysiologically-confirmed denervated muscles in the hand and forearm were analyzed – one extrinsic (Extensor Carpi Ulnaris - ECU) and one intrinsic (1st Dorsal Interosseus - IOD1). Muscles were stimulated for 33 min, five times per week over a 12-weeks period. Using ultrasonography (USG), muscle thickness (MT) and pennation angle (PA) of these muscles were determined at start and end of the stimulation period. Findings MT of IOD1 increased from 6·3 mm (± 3·2 mm) to 9·2 mm (± 2·4 mm) ( p = 0·004) and the PA from 5·5° (± 3·0°) to 11° (± 2·2°) ( p = 0·001). The corresponding values for the ECU were 5·5 mm (± 2·5 mm) to 7·0 mm (± 2·2 mm) ( p = 0·039) and 5·5° (± 3·4°) to 9·4° (± 3·8°) ( p = 0·005), respectively. The correlation of MT between baseline and completion was r = 0·58 ( p = 0·037) for the ECU and r = 0·63 ( p = 0·008) for the IOD1. Interpretation 12 weeks of direct muscle stimulation increases the MT and PA of the denervated intrinsic and extrinsic hand muscles studied. Funding Swiss Paraplegic Centre, Switzerland

Effects of tail nerve electrical stimulation on the activation and plasticity of the lumbar locomotor circuits and the prevention of skeletal muscle atrophy after spinal cord transection in rats

“…Furthermore, several studies have confirmed that the recovery of skeletal muscle innervation is beneficial for the muscles to recruit neurotrophin and achieve regeneration 34–36 . Subsequently, the muscle fibers also secreted myogenic trophic factors to influence the survival and function of motoneurons in a retrograde manner 37 . In addition, some studies have reported that electrical stimulation of the skeletal muscle in situ can prevent atrophy; this might be because of improvements of muscle circulation and metabolism 24,30,38 .…”

Influence of shortwave laser therapy on morphometric parameters of sciatic nerve regeneration after experimental neurorrhaphy

“…Each 10-minute procedure consisted of two parts: the first part (5 minutes) -short-wave laser stimulation of peripheral segments, the second part (20 minutes) -short-wave LT of the nerve trunk proximal to the level of damage. For shortwave LT [8] sciatic nerve, the SN trunk in the middle third of the thigh was irradiated. The procedures were performed every other day (Monday, Wednesday, Friday).…”

A Prediction Model for Various Treatment Pathways of Upper Extremity in Tetraplegia

“…Denervation atrophy results in a decrease in muscle fiber diameter and a partial to complete transformation of muscle tissue into connective and adipose tissue ( 35 ). In a previous study, we demonstrated that in early as well as chronic damage to the LMN, electrostimulation with long pulses enabled maintenance and restoration of muscle properties ( 20 ). In accordance with our results and with the research carried out on the muscles of the lower limb ( 36 ), an early start of this type of stimulation is recommended.…”

“…Since ES with long and short pulses has been recognized as a treatment method in rehabilitation, there is scientific evidence of its effectiveness (10). Afferent and efferent stimulation for neuromodulation (11,12), motor learning, and/or relearning of functions (13)(14)(15), strengthening of individual muscles or muscle groups (16,17), contracture prophylaxis and maintenance or improvement of muscle properties (18)(19)(20) are essential for the treatment of the upper limb in tetraplegia.…”