Effects of electrode size and placement on comfort and efficiency during low-intensity neuromuscular electrical stimulation of quadriceps, hamstrings and gluteal muscles

Abstract

Background Neuromuscular electrical stimulation (NMES) may prevent muscle atrophy, accelerate rehabilitation and enhance blood circulation. Yet, one major drawback is that patient compliance is impeded by the discomfort experienced. It is well-known that the size and placement of electrodes affect the comfort and effect during high-intensity NMES. However, during low-intensity NMES the effects of electrode size/placement are mostly unknown. Therefore, the purpose of this study was to investigate how electrode size and pragmatic placement affect comfort and effect of low-intensity NMES in the thigh and gluteal muscles. Methods On 15 healthy participants, NMES-intensity (mA) was increased until visible muscle contraction, applied with three electrode sizes (2 × 2 cm, 5 × 5 cm, 5 × 9 cm), in three different configurations on quadriceps and hamstrings (short-transverse (ST), long-transverse (LT), longitudinal (L)) and two configurations on gluteus maximus (short-longitudinal (SL) and long-longitudinal (LL)). Current–density (mA/cm2) required for contraction was calculated for each electrode size. Comfort was assessed with a numerical rating scale (NRS, 0–10). Significance was set to p < 0.05 and values were expressed as median (inter-quartile range). Results On quadriceps the LT-placement exhibited significantly better comfort and lower current intensity than the ST- and L-placements. On hamstrings the L-placement resulted in the best comfort together with the lowest intensity. On gluteus maximus the LL-placement demonstrated better comfort and required less intensity than SL-placement. On all muscles, the 5 × 5 cm and 5 × 9 cm electrodes were significantly more comfortable and required less current–density for contraction than the 2 × 2 cm electrode. Conclusion During low-intensity NMES-treatment, an optimized electrode size and practical placement on each individual muscle of quadriceps, hamstrings and gluteals is crucial for comfort and intensity needed for muscle contraction.

Knee extensor force production and discomfort during neuromuscular electrical stimulation of quadriceps with and without gluteal muscle co-stimulation

“…The electrode placement and size were based on a previous study comparing different pre-determined electrode configurations (Flodin et al 2022 ). Self-adhesive electrodes (Compex Snap, Performance, DJO Global, USA) were used to apply the NMES.…”

Neuromuscular electrical stimulation in garments optimized for compliance

“…The higher frequencies within the range of 1-50 Hz, when using standard gel electrodes, have been suggested to reduce the current amplitudes required to produce muscle contraction (Baker et al 1993;Flodin et al 2022;Gobbo et al 2014;Mettler et al 2018). Previous studies which included evaluation of comfort have suggested a frequency of around 36 Hz to be comfortable while at the same time not causing excessive muscle fatigue (Baker et al 1993;Breen et al 2012;Broderick et al 2014;Lyons et al 2002).…”

A randomised controlled trial of the non‐inferiority of erector spinae plane block vs. thoracic paravertebral block for laparoscopic nephro‐ureterectomy

“…The outcome that determined sample size was cumulative sufentanil equivalents at 24 postoperative hours. Additional analgesic measures were average pain scores at rest and on movement for both incision pain and intra‐abdominal pain to 24 h. Other outcomes were time to first participant‐administered sufentanil, the number of sufentanil boluses demanded and delivered within 48 h and the doses of additional analgesics to 48 h. We also recorded: the quality of recovery‐15 score at 24 h; sleep quality during the first two postoperative nights; nausea or vomiting to 48 h; complications; time to drain removal; time to ingestion and ambulation; time to hospital discharge; and estimated costs [24–26].…”