From: Assessment of muscle activity using electrical stimulation and mechanomyography: a systematic review
Authors | Sensor and electrode type | Electrode site | Dataset | Methodology | Results |
---|---|---|---|---|---|
Study 1: analysis of surgical monitoring | |||||
[92] | MMG: (SentioMMG, Sentio, LLC, Wixom, MI, USA) | VM, TA, BF and gastrocsoleus | 15 subjects with herniated nucleus pulposus (HNP), 31 subjects with lateral recess stenosis | The stimulation current was measured beyond 1Â mA after passing a ball-tripped sterile probe onto the surgical field. MMG signals were recorded to indicate the lowest current at which a motor action potential was measured. The stimulation current was increased to evoke MMG | The affected nerve root maintained a stimulus threshold of 1Â mA following decompression but exhibited an increased MMG amplitude |
Remark: the method is adequate fir root decompression and provides direct feedback to the surgeon | |||||
Future work: the threshold change among patients with acute and chronic impingement should be studied, and the valuable measurements obtained from advanced IONM MMG for quantifying changes in health pre- and post-decompression and their relationship to post-operative clinical outcomes should be investigated | |||||
Study 2: analysis of neuromuscular monitoring | |||||
[89] | MMG: piezo-electric (diameter = 1.6 cm, model 1010, Grass Instruments, Astro-Med, Inc., West Warwick, RI, USA; frequency = 2.5 Hz to 5 kHz, output = 20–40 mV) | Adductor pollicis and VM | 4 male and 8 female subjects, age 47 ± 21 years, weight 75 ± 8 kg, height 165 ± 12 cm | Mivacurium was injected for 5 min after the ulnar nerve and IM branches of the femoral nerve were supramaximally stimulated for 12 s with a 70-mA maximum current using a constant current stimulator. Acoustic signals were recorded from both muscles | The control twitch amplitude of the adductor pollicis was more significant than that of the VM |
Remark: the VM was associated with a shorter onset time, a less pronounced maximal effect and more rapid recovery of the NMB compared with the adductor pollicis | |||||
Study 3: comparison of KMG and EMG for clinical monitoring | |||||
[90] | EMG: \({\mathrm{Datex}}^{\mathrm{TM}}\) electrosensor; KMG: KMG sensor (Datex M-NMT MechanoSensor™) | Adductor pollicis | 27 female subjects, age 18–65 years | NMB was measured after injection of anesthesia, and NMT was measured after supramaximal stimulation for 5 min with 5-s pulses at 50 Hz; the Bland–Atman method was used to determine the difference between MMG and EMG | KMG overestimated the EMG due to variation from 65 to 100%, and these sensors cannot be used interchangeably |
Remark: KMG and EMG sensors cannot be used interchangeably | |||||
Future work: the use of KMG for monitoring a clinical endpoint should be verified | |||||
Study 4: analysis of diaphragm contractility using MMG | |||||
[91] | ES: (Neuropack MEB-9100, Nihon Kohden Inc., Tokyo, Japan); MMG: accelerometer (MPS110, MediSens Inc., Saitama, Japan) | Right phrenic nerve | 21 young subjects, age 22.5 ± 3.2, height 165.3 ± 78.6 m, weight 56.5 ± 8.1 kg; and 20 elderly subjects, non-smokers, age 70.9 ± 4.4 years, height 157.9 ± 8.2 m, weight 53.4 ± 8.5 kg, smokers, age 74.2 ± 5.9 years, height 154.8 ± 9.1 m, weight 51.4 ± 9.1 kg | The MMG signals from a contractile diaphragm were recorded after stimulation of the phrenic nerve. The correlations between diaphragmatic MMGs and respiratory parameters were assessed using Pearson correlation coefficients (significant if p < 0.05) | The correlations between diaphragmatic MMGs and respiratory parameters were significant (p < 0.05) |
Remark: diaphragmatic MMG was strongly correlated with inspiratory muscle strength and might reflect the diaphragmatic contractility more directly and with higher sensitivity than the conventional method |