Reliability of EMG activity in complete denture users during simulation of activities of daily living

Abstract

Purpose: To describe a kinesiologic EMG method and determine the reliability of EMG activity of representative muscles of mastication (temporal, masseter), posture of neck (sternocleidomastoid, trapezius) and trunk (rectus abdominis, paravertebral), and lower extremity strength (rectus femoris, medial gastrocnemius) during simulation of activities of daily living.Methods: Ten edentulous healthy women (age: 58.2±5.6 yr old) were tested with and without their dentures. EMG signals were recorded for each subject during three trials of each kinesiologic test: to stand up/sit down on a chair (TC), to rise/lie down in the bed (TB), and to lift/lower bags (TW). The same-day reprodutibility of the EMG values was estimated by test-retest reliability analyses. For each test (TC, TB, and TW) the intraclass correlation coefficient (ICC) and 95% confidence interval were estimated stratified by muscle, presence or not of complete dentures, and movement during the test (up and down) considering the three repetitions per subject to assess consistency.Results: All muscles showed activation during the tests. The method yielded moderate to high ICCs; the highest test-retest reliability levels were estimated for the sternocleidomastoid (0.82-0.97) and paravertebral (0.86-0.99) muscles.Conclusion: These findings suggest that the described kinesiologic EMG method showed satisfactory reliability in this sample.Key words: Electromyography; complete dentures; activities of daily living ResumoObjetivo: Descrever uma metodologia de EMG cinesiológica e determinar a reprodutibilidade da atividade eletromiográfica dos músculos mastigatórios (m. temporal e m. masseter), posturais do pescoço (mm. esternocleidomastoideo e trapézio), posturais do tronco (mm. reto abdominal e paravertebrais) e de força das extremidades inferiores (mm. reto femoral e gastrocnemius medial) durante simulação de atividades de vida diária (AVDs).Metodologia: A amostra foi constituída por dez mulheres saudáveis, usuárias de prótese total bimaxilar, com idade média de 58,2 anos. Foram realizados três testes AVDs: levantar/ sentar da cadeira (TCAD), levantar/deitar na cama (TCAM) e pegar/largar sacolas (TSAC). A reprodutibilidade dos valores EMG foi analisada por teste-reteste. Para cada teste AVD foram estimados coeficiente de correlação intraclasse (CCIC) e intervalo de confiança de 95% com estratificação por músculo, condição com e sem prótese (suporte oclusal) e movimento durante o teste, considerando três repetições por sujeito para avaliar consistência.

Duration and sequence of muscular activation in dentate individuals and complete denture wearers during simulation of activities of daily living

“…The paravertebral and rectus femoris muscles can be considered as strength muscles for the stand‐up movement as they display the largest EMG amplitudes and an intermediate position in the sequence of activation. A tendency for earlier activation of the rectus femoris and gastrocnemius muscles was observed when the occlusal support was removed, which suggests that the strength muscles are needed more in situations of occlusal impairment.…”

“…Surface EMG was used to record the muscle activity of eight muscles, on the right side: masticatory (temporal, masseter); head and neck (sternocleidomastoid, trapezius); trunk (rectus abdominis, paravertebral); and lower limb (rectus femoris, gastrocnemius medialis). Disposable, self‐adhesive, silver‐silver chloride electrodes (Noraxon, Scottsdale, AZ, USA), with bipolar configuration, 10 mm diameter and 20 mm interelectrode distance between centers, were placed over the bellies of the selected muscles parallel to muscular fibers, according to standard anatomic landmarks (Table ). One reference ground silver‐silver chloride electrode (Medi‐Trace 200 adult; Graphic Controls, New York, NY, USA) was attached over the left tibia.…”

“…Electromyographic signals were recorded during three kinesiologic tests simulating ADL: performing stand up/sit down in a chair (Chair Test); performing sit up/lie down in the bed (Bed Test); and when lifting/lowering bags (Bag Test) (Table ). Edentulous women performed the trials with and without their CDs (i.e.…”

Normalization of EMG Signals: To Normalize or Not to Normalize and What to Normalize to?

“…Unfortunately, there is no consensus as to which test produces maximal activation in all individuals in any given muscle. [28,29] • combined shoulder elevation/arm flexion/abduction in the scapular plane at 90° abduction [30] • shoulder abduction in scapular plane at 90° abduction [31,32] • lumbar extension [33] supraspinatus…”

“…• ankle plantar flexion, ankle, knee and hip in neutral position (prone) [38,45] • ankle plantar flexion, ankle -15°, knee flexed 30° [44] • ankle plantar flexion, mid ankle position (standing unilateral -body weight) [47] • ankle plantar flexion (supine) [33] soleus • ankle plantar flexion, mid ankle position (prone) [38] • ankle plantar flexion, ankle in neutral position; knee and hip flexed 90° (quadruped position) [45,46] tibialis anterior • ankle dorsi flexion, ankle, knee and hip in neutral position (supine) [45] • ankle dorsi flexion, ankle in neutral position; knee and hip flexed 90° (quadruped position) [46] Although the repeatability of the EMG recorded during MVICs within individuals on the same day has been questioned [34], the majority of studies indicate that the reliability of MVICs within individuals on the same day is high [42,48,49]. High repeatability requires proper guidance of the subjects to perform the tests identically with each repetition, familiarity of the subjects with the production of maximum effort and the avoidance of fatigue.…”