Neuromuscular electrical stimulation training results in enhanced activation of spinal stabilizing muscles during spinal loading and improvements in pain ratings

Abstract

Low back pain is associated with dysfunction in recruitment of muscles in the lumbopelvic region. Effective rehabilitation requires preferential activation of deep stabilizing muscle groups yet training these muscles poses challenges in a clinical setting. This study was carried out in order to quantify the response of deep stabilizing muscles (transverses abdominis and deep fibres of multifidus) to a period of training using a novel neuromuscular electrical stimulation (NMES) application in a group of patients with chronic low back pain. Analysis of results revealed clinically and statistically significant improvements in indicators of both muscle groups' performance, as evidenced by ultrasound evaluation of activation during voluntary activity. These improvements were associated with significant improvements in self reported pain levels, suggesting that NMES has an important role to play in CLBP rehabilitation.

Activations of Deep Lumbar Stabilizing Muscles by Transcutaneous Neuromuscular Electrical Stimulation of Lumbar Paraspinal Regions

“…Previous studies have reported on the ability of transcutaneous NMES applied to the lateral abdominal surface to activate deep lumbar stabilizing muscles [16,17,18,19]. Porcari et al [16] reported significant improvements in muscular strength and endurance of the abdominal region, after applying a belt type NMES to the abdominal wall.…”

“…Porcari et al [16] reported significant improvements in muscular strength and endurance of the abdominal region, after applying a belt type NMES to the abdominal wall. Coghlan et al [18,19] reported that NMES applied to the abdominal wall and paralumbar area induced increases in thickness of abdominal deep lumbar stabilizing muscles and lumbar multifidus muscles. However, the ability of transcutaneous NMES, applied to the lumbar paraspinal region, to activate deep lumbar stabilizing muscles has not been investigated thoroughly.…”

“…Glaser et al [20] reported higher lumbar spine function in a NMES paralumbar area group than in a control group; but RUSI was not used. In this study, relatively small electrodes (5 cm×5 cm) were utilized [16,18,19], which allowed us to specifically activate the LM without simultaneously activating abdominal lumbar stabilizing muscles. The present study is the first to investigate the effect of NMES on only the paraspinal region using RUSI.…”

“…Neuromuscular electrical stimulation (NMES) is an effective tool for preferentially stimulating contractions in deep lumbar stabilizers [16,17,18,19,20,21]. Real-time ultrasound imaging (RUSI) is useful for quantifying abdominal and lumbar trunk musculatures, and it has excellent reliability and validity.…”

“…Changes in muscle thickness have been reported to be linearly related to specific contraction levels, as determined by fine wire electromyography (EMG) [22]. Moreover, researchers have reported on the effectiveness of NMES for training deep spinal muscles, as determined by RUSI [18,19,21]; and muscle activation induced by NMES were beneficial for patients with LBP [19]. However, changes in the thicknesses of LM and abdominal deep lumbar stabilizing muscles during NMES are applied only to the paralumbar area and have not been investigated in detail.…”