Vanessa Monteiro-Pedro

Avaliação eletromiográfica dos músculos estabilizadores da patela durante exercício isométrico de agachamento em indivíduos com síndrome da dor femoropatelar

El objetivo de este trabajo fue el de comparar la actvividad electrica de los musculos vasto medial obliquo (VMO), vasto lateral longo (VLL) y vasto lateral oblicuo (VLO) durante los ejercicios isometricos de agachamiento wall slide a 45o (WS 45o) e 60o (WS 60o) de flexion de rodilla. Fueron evaluadas 15 mujeres clinicamente saludables con sindrome de dolor femoropatelar (SDFP). Los registros fueron obtenidos por electrodos activos simples conectados a un electromiografo durante la contraccion isometrica voluntaria maxima (CIVM) de WS 45o y de WS 60o. Los datos fueron analizados por la media de los valores de Root Mean Square - RMS de senal eletromiografica, normalizada por la media del RMS obtenido en el agachamiento a 75o de flexion de la rodilla. El analisis estatistico empleado fue el test ANOVA two way (p < 0,05) y el test Duncan post hoc (p < 0,05). Los resultados revelaron que el ejercicio WS 60o presento mayor atividad electrica en los musculos VMO, VLL y VLO cuando es comparado a WS 45o, para los grupos control y SDFP. Durante el WS 60o, para el grupo control, no fueran observadas diferencias en la actividad de los musculos VMO, VLO y VLL, sugeriendo un equilibrio en la actividad electrica de estos musculos, en cuanto que en el WS 45o, el musculo VLL presento una mayor activacion cuando comparado con los musculos VMO y VLO. Para el grupo SDFP, este equilibrio entre las porciones medial y lateral del musculo cuadriceps fue observado en los dos tipos de exercicios. Estes datos sugieren que WS 60o, para el grupo control, puede ser mas efectivo para los programas de fortalecimiento muscular. Con todo para el grupo con SDFP, ambos ejercicios pueden ser indicados durante el programa de rehabilitacion. Ademas, la ausencia de diferencias en la actividad eletromiografica de los musculos VMO, VLO y VLL entre los grupos, de este estudio, sugiere que el desequilibrio muscular puede no ser un fator predisponente de la SDFP.

A influência da altura do step no exercício de subida posterior: estudo eletromiográfico em indivíduos sadios e portadores da síndrome da dor femoropatelar

The aim of this study was to evaluate the influence of the step height in the electric activity of the vastus medialis oblique (VMO), vastus lateralis longus (VLL) e vastus lateralis oblique (VLO) on backward step-up exercise. Twenty-seven females, being 15 healthy (21.13 ± 2.17 years old) and 12 with Patellofemoral Pain Syndrome PPS (21.08 ± 2.31 years old) have participated in the study. The electric activity was recorded by surface electrodes. The volunteers performed the backward step-up exercise in two different heights: with the knee joint flexion at 45o and at 75o. The whole electric signal normalized by the average of repetitions was used to study the VMO:VLO and VMO:VLL activation ratio. The two-way ANOVA and Duncan post hoc (p < 0.05) showed that in the PPS group, the VMO: VLO and VMO: VLL ratio was greater at 45o than at 75o angle. In the Control group, the VMO: VLO ratio was greater at 45o than at 75o, while the VMO: VLL ratio was greater at 75o. The results of this study suggest that backward step-up exercise at 45o can be used for PPS treatment programs because it activated the VMO muscle in a more selective way.

Electromyographic activity evaluation of the patella muscles during squat isometric exercise in individuals with patellofemoral pain syndrome

El objetivo de este trabajo fue el de comparar la actvividad electrica de los musculos vasto medial obliquo (VMO), vasto lateral longo (VLL) y vasto lateral oblicuo (VLO) durante los ejercicios isometricos de agachamiento wall slide a 45o (WS 45o) e 60o (WS 60o) de flexion de rodilla. Fueron evaluadas 15 mujeres clinicamente saludables con sindrome de dolor femoropatelar (SDFP). Los registros fueron obtenidos por electrodos activos simples conectados a un electromiografo durante la contraccion isometrica voluntaria maxima (CIVM) de WS 45o y de WS 60o. Los datos fueron analizados por la media de los valores de Root Mean Square - RMS de senal eletromiografica, normalizada por la media del RMS obtenido en el agachamiento a 75o de flexion de la rodilla. El analisis estatistico empleado fue el test ANOVA two way (p < 0,05) y el test Duncan post hoc (p < 0,05). Los resultados revelaron que el ejercicio WS 60o presento mayor atividad electrica en los musculos VMO, VLL y VLO cuando es comparado a WS 45o, para los grupos control y SDFP. Durante el WS 60o, para el grupo control, no fueran observadas diferencias en la actividad de los musculos VMO, VLO y VLL, sugeriendo un equilibrio en la actividad electrica de estos musculos, en cuanto que en el WS 45o, el musculo VLL presento una mayor activacion cuando comparado con los musculos VMO y VLO. Para el grupo SDFP, este equilibrio entre las porciones medial y lateral del musculo cuadriceps fue observado en los dos tipos de exercicios. Estes datos sugieren que WS 60o, para el grupo control, puede ser mas efectivo para los programas de fortalecimiento muscular. Con todo para el grupo con SDFP, ambos ejercicios pueden ser indicados durante el programa de rehabilitacion. Ademas, la ausencia de diferencias en la actividad eletromiografica de los musculos VMO, VLO y VLL entre los grupos, de este estudio, sugiere que el desequilibrio muscular puede no ser un fator predisponente de la SDFP.

Electromyographic and magnetic resonance imaging evaluations of individuals with patellofemoral pain syndrome

OBJECTIVES To analyze the electrical activity of the vastus medialis obliquus (VMO), vastus lateralis longus (VLL) and vastus lateralis obliquus (VLO) muscles of individuals with patellofemoral pain syndrome (PFPS) during maximum voluntary isometric contraction (MVIC) of lower leg extension with the knee at 30 degrees; to assess pain using a visual analogue scale (VAS); and to assess patellar positioning using magnetic resonance imaging (MRI). METHODS Twelve women with PFPS and 12 clinically normal women were evaluated. They performed five MVICs of lower leg extension at 30 degrees for electromyographic (EMG) analysis. Using MRI, the sulcus angle (SA), congruence angle (CA), patellar tilt angle (PTA) and patellar displacement (PD) were obtained. The following statistical tests were used: analysis of variance (ANOVA) for repeated measurements to assess EMGs; Mann-Whitney U test to analyze MRIs; Pearsons (r) correlation test between EMGs and MRIs; and one-way ANOVA to evaluate pain (p < or = 0.05). RESULTS In the PFPS group, there was greater electrical activity in the VLL than in the VMO. In both groups, there was greater electrical activity in the VMO and VLL than in the VLO. In the PFPS group, the MRI showed higher SA and lower CA values, and there was a negative correlation between the VMO and the PTA. CONCLUSION The data suggest that, in individuals with PFPS, greater electrical activity in the VLL combined with an increased SA and a decreased CA may contribute to patellar instability.

Efeito da rotação do quadril na síndrome da dor femoropatelar

ABSTRACTEffect of Hip Rotation on Patellofemoral Pain Syndrome Objective: The purpose of this study was to evaluate the effect of hip rotation on the electrical activity of the Vastus MedialisObliquus (VMO), Vastus Lateralis Obliquus (VLO) and Vastus Lateralis Longus (VLL) muscles when squatting with 45o kneeflexion, in association with the neutral position, 45o lateral rotation and 15 and 30o medial hip rotation. Method: 27 women wereevaluated: 15 healthy women as a control group (21.1 ± 2.1 years) and 12 subjects with patellofemoral pain syndrome (PFPS)(21.0 ± 2.3 years). The electrical activity of the quadriceps muscle was detected using simple active differential surface electrodes,an eight-channel electromyography system and the Aqdados 7.2.6 software. The data were normalized by the mean squattingpercentage at 75o with the hip in the neutral position – RMS (μV). Two-way ANOVA with repeated measurements followed bythe Tukey post hoc test (p≤0.05) was used for statistical analysis. Results: The results revealed interaction between groups andmuscles (p=0.00), independent of hip position (p=0.39), and there was no interaction between groups and hip positions (p=0.96).The VMO and VLL muscles of the PFPS group showed significantly greater electrical activity than did VMO (p=0.00) and VLL(p=0.04) muscles from the control group. On the other hand, the electrical activity of the VLO muscle did not present any sig-nificant difference between the groups (p=0.99). Conclusion: Under the experimental conditions utilized, the results suggestedthat hip rotation did not alter the electrical activity of the quadriceps portions in either group when squatting with 45o knee flexion.

The effect of hip abduction on the EMG activity of vastus medialis obliquus, vastus lateralis longus and vastus lateralis obliquus in healthy subjects

Study designControlled laboratory study.ObjectivesThe purposes of this paper were to investigate (d) whether vastus medialis obliquus (VMO), vastus lateralis longus (VLL) and vastus lateralis obliquus (VLO) EMG activity can be influenced by hip abduction performed by healthy subjects.BackgroundSome clinicians contraindicate hip abduction for patellofemoral patients (with) based on the premise that hip abduction could facilitate the VLL muscle activation leading to a VLL and VMO imbalanceMethods and measuresTwenty-one clinically healthy subjects were involved in the study, 10 women and 11 men (aged X = 23.3 ± 2.9). The EMG signals were collected using a computerized EMG VIKING II, with 8 channels and three pairs of surface electrodes. EMG activity was obtained from MVIC knee extension at 90° of flexion in a seated position and MVIC hip abduction at 0° and 30° with patients in side-lying position with the knee in full extension. The data were normalized in the MVIC knee extension at 50° of flexion in a seated position, and were submitted to ANOVA test with subsequent application of the Bonferroni multiple comparisons analysis test. The level of significance was defined as p ≤ 0.05.ResultsThe VLO muscle demonstrated a similar pattern to the VMO muscle showing higher EMG activity in MVIC knee extension at 90° of flexion compared with MVIC hip abduction at 0° and 30° of abduction for male (p < 0.0007) and MVIC hip abduction at 0° of abduction for female subjects (p < 0.02196). There were no statistically significant differences in the VLL EMG activity among the three sets of exercises tested.ConclusionThe results showed that no selective EMG activation was observed when comparison was made between the VMO, VLL and VLO muscles while performing MVIC hip abduction at 0° and 30° of abduction and MVIC knee extension at 90° of flexion in both male and female subjects. Our findings demonstrate that hip abduction do not facilitated VLL and VLO activity in relation to the VMO, however, this study included only healthy subjects performing maximum voluntary isometric contraction contractions, therefore much remains to be discovered by future research

Relação eletromiográfica integrada dos músculos vasto medial oblíquo e vasto lateral longo na marcha em sujeitos com e sem síndrome de dor femoropatelar

The aim of this study was to determine if there is difference between the vastus medialis oblique and vastus lateralis longus (VMO/VLL) muscles activation during treadmill gait level and ascending to 5% degree between healthy subjects and others with patellofemoral pain syndrome. Electromyographic data from the VMO and VLL muscles were obtained in 15 subjects without and 12 with patellofemoral pain syndrome (PFPS) during treadmill gait with and without 5 degrees inclination. The value of the VMO/VLL ratio was determined from the mean of 8 strides, in each condition, during 12 s. The t-Student test did not show significant difference in the VMO/VLL ratio between the two groups, regardless the condition. Although there was not significant difference, the subjects of the control group showed higher values in the VMO/VLL ratio in the two tested conditions than the subject of the PFPS group. The findings suggest that the ratio of the electric activity of the VMO and VLL muscles in individuals with and without SDFP is equal in the gait on flat surface as well as slanted to 5 degrees.

Tempo de início da atividade elétrica dos estabilizadores patelares na marcha em sujeitos com e sem síndrome de dor femoropatelar

Abstract Introduction : The patellofemoral pain syndrome (PFPS) it is a common problem affecting one in each four people. Alteration in the onset time and intensity of contraction of the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles are considered important factors in the aetiology of PFPS. However, few studies exist about the function of the oblique portion of the vastus lateralis (VLO) and none on the onset time of VLO in functional activities in normal subjects and with PFPS. Objective : The purpose of this study was to investigate the onset time in the VMO, VLO and VL longus (VLL) muscles during the gait. Materials and methods : Sample was formed by 15 subjects without and 12 with PFPS. Electromyographic data were obtained of the VMO, VLO and VL muscles during treadmill walking with and without inclination. The relative difference in the onset time (DRO) among VMO-VLL and VMO-VLO were determined from the average of 3 strides. Results : There was dif-ference among the subject with and without PFPS in relation to DRO among VMO-VLL. In the subject with PFPS the order at the beginning of the electric activity it was VLL following for VLO and after VMO. In the individuals without the pathology the order was different, first VMO, after VLO and last VLL.

Integrated electromyographic ratio of the vastus medialis oblique and vastus lateralis longus muscles in gait in subjects with and without patellofemoral pain syndrome

The aim of this study was to determine if there is difference between the vastus medialis oblique and vastus lateralis longus (VMO/VLL) muscles activation during treadmill gait level and ascending to 5% degree between healthy subjects and others with patellofemoral pain syndrome. Electromyographic data from the VMO and VLL muscles were obtained in 15 subjects without and 12 with patellofemoral pain syndrome (PFPS) during treadmill gait with and without 5 degrees inclination. The value of the VMO/VLL ratio was determined from the mean of 8 strides, in each condition, during 12 s. The t-Student test did not show significant difference in the VMO/VLL ratio between the two groups, regardless the condition. Although there was not significant difference, the subjects of the control group showed higher values in the VMO/VLL ratio in the two tested conditions than the subject of the PFPS group. The findings suggest that the ratio of the electric activity of the VMO and VLL muscles in individuals with and without SDFP is equal in the gait on flat surface as well as slanted to 5 degrees.

Relación electromiográfica integrada de los músculos vasto medial oblicuo y vasto lateral largo en marcha en individuos con y sin síndrome de dolor femoropatelar

The aim of this study was to determine if there is difference between the vastus medialis oblique and vastus lateralis longus (VMO/VLL) muscles activation during treadmill gait level and ascending to 5% degree between healthy subjects and others with patellofemoral pain syndrome. Electromyographic data from the VMO and VLL muscles were obtained in 15 subjects without and 12 with patellofemoral pain syndrome (PFPS) during treadmill gait with and without 5 degrees inclination. The value of the VMO/VLL ratio was determined from the mean of 8 strides, in each condition, during 12 s. The t-Student test did not show significant difference in the VMO/VLL ratio between the two groups, regardless the condition. Although there was not significant difference, the subjects of the control group showed higher values in the VMO/VLL ratio in the two tested conditions than the subject of the PFPS group. The findings suggest that the ratio of the electric activity of the VMO and VLL muscles in individuals with and without SDFP is equal in the gait on flat surface as well as slanted to 5 degrees.