Interrater and Intrarater Reliability and Minimum Detectable Change of Ultrasound for Active Myofascial Trigger Points in Upper Trapezius Muscle in Individuals With Shoulder Pain.

OBJECTIVE: We sought to investigate the interrater and intrarater reliability of ultrasound and the minimum detectable change (MDC) for the trigger points (TrPs) active in the upper trapezius (UT) muscle in individuals with shoulder pain. METHODS: Forty individuals with shoulder pain were investigated for the presence of active TrPs in the UT muscle by means of ultrasound for the parameters of gray scale, muscle thickness of UT muscle at rest, and contraction and area of TrPs. The intrarater reliability was performed on 2 days, and interrater reliability on the same day. For the gray scale, the reliability was evaluated using the kappa coefficient (κ), while the other parameters were measured by the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and MDC. RESULTS: For the gray scale, the intrarater agreement was almost perfect (κ = 1.00) and the interrater agreement was substantial (κ = 0.75). The intrarater and interrater reliability were excellent for most of the parameters, except for the area of TrPs (intrarater: ICC = 0.71, substantial; interrater: ICC = 0.52, substantial). The MDC for intrarater reliability varied between 0.04 and 0.05 (SEM% between 2.4% and 38.87%), and that for interrater reliability ranged from 0.05 to 0.07 (SEM% between 3.18% and 55.10%), with a higher value for area. CONCLUSION: Parameters such as gray scale, resting muscle thickness, and muscle contraction of the UT muscle, obtained through ultrasound, showed excellent intrarater and interrater reliability with low SEM%. The intrarater and interrater reliability for the area deserves a caveat regarding their use.

Two-dimensional ultrasound and ultrasound elastography imaging of trigger points in women with myofascial pain syndrome treated by acupuncture and electroacupuncture: a double-blinded randomized controlled pilot study.

Chronic pain has been often associated with myofascial pain syndrome (MPS), which is determined by myofascial trigger points (MTrP). New features have been tested for MTrP diagnosis. The aim of this study was to evaluate two-dimensional ultrasonography (2D US) and ultrasound elastography (UE) images and elastograms of upper trapezius MTrP during electroacupuncture (EA) and acupuncture (AC) treatment. 24 women participated, aged between 20 and 40 years (M ± SD = 27.33 ± 5.05) with a body mass index ranging from 18.03 to 27.59 kg/m2 (22.59 ± 3.11), a regular menstrual cycle, at least one active MTrP at both right (RTPz) and left trapezius (LTPz) and local or referred pain for up to six months. Subjects were randomized into EA and AC treatment groups and the control sham AC (SHAM) group. Intensity of pain was assessed by visual analogue scale; MTrP mean area and strain ratio (SR) by 2D US and UE. A significant decrease of intensity in general, RTPz, and LTPz pain was observed in the EA group (p = 0.027; p < 0.001; p = 0.005, respectively) and in general pain in the AC group (p < 0.001). Decreased MTrP area in RTPz and LTPz were observed in AC (p < 0.001) and EA groups (RTPz, p = 0.003; LTPz, p = 0.005). Post-treatment SR in RTPz and LTPz was lower than pre-treatment in both treatment groups. 2D US and UE effectively characterized MTrP and surrounding tissue, pointing to the possibility of objective confirmation of subjective EA and AC treatment effects.

Avaliação de pontos-gatilho miofasciais por imagens de ultrassom e elastografia ultrassonográfica em mulheres tratadas pela acupuntura, eletroacupuntura e acupuntura sham: estudo piloto / Two-dimensional ultrasound and ultrasound elastography imaging of myofascial trigger points in women treated by acupuncture, electroacupuncture and sham acupuncture: pilot study

O presente estudo, de caráter experimental, teve como objetivo a avaliação de pontos-gatilho miofasciais (PG) do músculo trapézio descendente (TPz) por imagens de ultrassonografia bidimensional em escala de cinza (US 2D) e elastografia ultrassonográfica (ELASTO), bem como avaliar a eficácia das técnicas de acupuntura (AC) e eletroacupuntura (EA) na diminuição da dor em mulheres com síndrome da dor miofascial (SDM) associada a queixas de dor nas regiões de cabeça, pescoço e parte superior do tronco. Uma amostra de conveniência de 24 voluntárias, com idades entre 20 e 40 anos (27,33±5,05), IMC entre 18,03 e 27,09 Kg/m² (22,59±3,11), ciclo menstrual regular, presença de ao menos um PG ativo em ambos os TPz, queixa de dor local e/ ou referida há pelo menos seis meses foi selecionada para o estudo. Após a assinatura do Termo de Consentimento Livre e Esclarecido (TCLE), as voluntárias foram randomizadas em três grupos, sendo: dois grupos de tratamento (AC e EA) e um grupo controle (SHAM). Oito sessões de tratamento foram então realizadas, duas vezes por semana, durante aproximadamente um mês, levando em consideração o ciclo menstrual das voluntárias. Imagens do músculo trapézio foram adquiridas pelas técnicas de US 2D e ELASTO para avaliação e diagnóstico das propriedades mecânicas e viscoelásticas do tecido miofascial e a comparação dessas características pré e pós-tratamento. Nas imagens de US 2D, as áreas dos PG foram mensuradas. Nos elastogramas adquiridos pela ELASTO, o índice de resistência (IR) foi calculado. Tanto as voluntárias quanto o examinador eram cegos em relação aos grupos. A intensidade de dor geral e localizada nos TPz direito e esquerdo (TPzD e TPzE, respectivamente) pré e pós-tratamento foi mensurada com o auxílio da escala visual analógica (EVA). A ocorrência de fatores influenciadores e as fases do ciclo menstrual foram monitoradas. Os dados foram analisados quanto à normalidade e simetria. Na avaliação intragrupo todos os dados apresentaram distribuição normal, sendo analisados pelo teste t student para dados pareados. Observou-se diminuição da intensidade de dor geral para o grupo AC (P<0,001) e de dor geral e local para a EA (geral, P=0,027; TPzD, P<0,001; TPzE, P=0,005); sem resultados estatisticamente significantes para o grupo SHAM (geral, P=0,296; TPzD, P=0,052; TPzE, P=0,198). Quanto à avaliação de PG nas imagens de US 2D , observou-se diminuição da área do PG para ambos os TPzD e TPzE nos grupos AC (TPzD e TPzE, P<0,001) e EA (TPzD, P=0,003; TPzE, P=0,005); e não para o grupo SHAM (TPzD, P=0,117; TPzE, P=0,093). Em relação à ELASTO, os dados não apresentaram significância estatística para a amostra analisada, contudo, o IR de ambos os lados apresentou-se menor após o tratamento para a EA e AC, e maior para a SHAM. Na comparação entre grupos, diferenças estatisticamente significantes não foram observadas para as variáveis testadas. Os resultados do presente trabalho sugerem a possibilidade de utilização da US 2D e ELASTO na caracterização do tecido miofascial e de PG, apontando para a possibilidade de confirmação objetiva de efeitos subjetivos de tratamentos propostos para a SDM. Ainda, as técnicas de AC e EA demonstraram eficácia no alívio da dor geral, sendo a efetividade da EA observada também na diminuição da intensidade de dor local. O nível de significância adotado foi ?=0,05.(AU)

The aim of this study was to evaluate upper trapezius (TPz) myofascial trigger points (MTrP) through two-dimensional ultrasonography (2D US) and ultrasound elastography (ELASTO) images, as well as, to evaluate the effectiveness of acupuncture (AC) and electroacupuncuture (EA) in decreasing pain in women with myofascial pain syndrome (MPS) associated with head, neck and upper back complaints. A convenience sample of 24 volunteer aged between 20 and 40 years (27.33±5.05 years), body mass index (BMI) from 18.03 to 27.09Kg/m² (22.59±3.11), presenting regular menstrual cycle, at least one active MTrP at both right and left TPz (RTPz and LTPz, respectively) and local or referred pain for up to six months were selected. After signing the Informed Consent Form (ICF), subjects were randomized into three groups, being: two treatment groups (AC and EA) and one control group (SHAM). Eight treatment sessions were than performed, two times per week, for nearly one month, considering each volunteer menstrual cycle. Pre, post-treatment Intensity of pain was assessed by visual analogue scale (VAS) as well as MTrP mean area and strain ratio (SR) by 2D US and ELASTO, respectively, in way to myofascial tissue mechanical and viscoelastic properties assessment and diagnosis. Both, volunteers and examiner were blinded for the three groups. Influencing factors and menstrual cycle phases were monitored. Data were analyzed for normality and symmetry. All intragroup data were normally distributed, so, were analyzed by Student¿s t test for paired data. Decrease in pain intensity was observed for AC (general, P<0.001) and EA (general, P=0.027; RTPz, P<0.001; LTPz, P=0.005); without any significant result for SHAM (general, P=0.296; RTPz, P=0.052; LTPz, P=0.198). Decreased MTrPs area occurred for both sides in AC (RTPz and LTPz, P<0.001) and EA (RTPz, P=0.003; LTPz, P=0.005); on the other hand, SHAM results were not significant (RTPz, P=0.117; LTPz, P=0.093). Concerning ultrasound elastography, although not statistically significant, post-treatment SR in both sides were lower than the beginning for EA and AC, and higher for SHAM group. Regarding within group comparison, no statistically significant difference were observed for the tested variables. 2D US and ELASTO presented the possibility of MTrPs and surrounding tissue diagnosis and characterization, pointing to the possibility of objective confirmation of subjective MPS treatment effects. Also, EA and AC were effective in decreasing general pain intensity, being EA also effective in local pain intensity relief. The level of significance was ?=0.05.(AU)