Knee angular displacement analysis in amateur ballet dancers: a pilot study

Ballet gestures are highly non-anatomical and physiological, leading to compensatory behaviors. The knee joint is most affected by this behavior, leading to an increase risk of injury. Our purpose is to describe the knee angular displacement in amateur dancers, during a demi-plié exercise, with emphasis on valgus mechanisms frequency. Methods: 192 demi-pliés collected in six amateur female dancers (mean age = 15.33 ± 1.37 years), were analyzed regarding sagittal and frontal plane angular displacement, with an electrogoniometer connected to a signal acquisition unit at 1000 Hz. Results: all subjects presented valgus peaks along the trials, despite the global varus tendency of the knee frontal plane behavior. A significant positive correlation between the frequency of valgus and practice time was noted. Discussion: A variable angular frontal displacement was observed, with some trials comprehending a high incidence of valgus peaks along the ascending or descending phase of the demi-plié exercise. Conclusion: the frontal knee angle behavior is variable. It may present fast peaks of valgus or an initial trend of varus/valgus that is different from the global varus trend. The analysis of the activity should be considered in the training. The practice time may be related to the observed behavior.

The effects of nutrition, puberty and dancing on bone density in adolescent ballet dancers.

Ballet dancers have on average a low bone mineral content (BMC), with elevated fracture-risk, low body mass index (BMI) for age (body mass index, kg/m2), low energy intake, and delayed puberty. This study aims at a better understanding of the interactions of these factors, especially with regard to nutrition. During a competition for pre-professional dancers we examined 127 female participants (60 Asians, 67 Caucasians). They averaged 16.7 years of age, started dancing at 5.8 years, and danced 22 hours/week. Assessments were made for BMI, BMC (DXA), and bone mineral apparent density (BMAD) at the lumbar spine and femoral neck, pubertal stage (Tanner score), and nutritional status (EAT-40 questionnaire and a qualitative three-day dietary record). BMI for age was found to be normal in only 42.5% of the dancers, while 15.7% had a more or less severe degree of thinness (12.6% Grade2 and 3.1% Grade 3 thinness). Menarche was late (13.9 years, range 11 to 16.8 years). Food intake, evaluated by number of consumed food portions, was below the recommendations for a normally active population in all food groups except animal proteins, where the intake was more than twice the recommended amount. In this population, with low BMI and intense exercise, BMC was low and associated with nutritional factors; dairy products had a positive and non-dairy proteins a negative influence. A positive correlation between BMAD and years since menarche confirmed the importance of exposure to estrogens and the negative impact of delayed puberty. Because of this and the probable negative influence of a high intake of non-dairy proteins, such as meat, fish, and eggs, and the positive association with a high dairy intake, ballet schools should promote balanced diets and normal weight and should recognize and help dancers avoid eating disorders and delayed puberty caused by extensive dancing and inadequate nutrition.

Pathomechanics of posterior ankle impingement syndrome in female ballet dancers

A dança é uma actividade de grande exigência atlética, que pode conduzir a um elevado número de lesões, particularmente na região do tornozelo, possivelmente devido à amplitude extrema do movimento articular de flexão plantar do mesmo, que os bailarinos, especialmente do sexo feminino possuem, para realizar a ponta e meia ponta tão características do ballet clássico (Kadel, 2006; Motta-Valencia, 2006; Russel, Kruse, Koutedakis, McEwan, Wyon, 2010). Estas posições de flexão plantar extrema produzem força excessiva na região posterior do tornozelo, o que muitas vezes pode resultar em conflito, dor e incapacidade, representando na maioria das vezes um desafio de diagnóstico. O síndrome do conflito posterior do tornozelo refere-se a um grupo de entidades patológicas que resultam da flexão plantar forçada do tornozelo, de forma repetitiva ou traumática, causando um conflito das estruturas ósseas e/ou de tecidos moles (Hamilton, Geppert, Thompson, 1996; Hamilton, 2008) . Os objectivos deste projecto são compreender os quais os factores de risco, mecânicos e funcionais que contribuem para a mecânica patológica da lesão descritos na literatura, e proceder a uma avaliação biomecânica do movimento de flexão plantar do tornozelo. Método. Realizar uma revisão sistemática de literatura dirigida á mecânica patológica do síndrome do conflito posterior do tornozelo em bailarinas e conduzir um estudo caso-controlo, cujo objectivo é avaliar, comparar e descrever o movimento da flexão plantar do tornozelo realizado ao efectuar os movimentos de ponta e meia-ponta, em bailarinas pré-profissionais com e sem lesão recorrente resultante do conflito posterior do tornozelo. Resultados. Não foram encontrados estudos relacionados especificamente com a mecânica patológica do tornozelo, no entanto vários estudos foram encontrados considerando as características clínicas e anatómicas assim como os procedimentos de tratamento, indicando que os principais factores de risco relacionados com a lesão se dividem em factores mecânicos e funcionais que quando combinados entre si e associados ao sobre-uso podem resultar no conflito posterior do tornozelo. Na avaliação do movimento foram observadas diferenças na actividade muscular entre os sujeitos com lesão e controlos, tendo sido possível a observação de um padrão na sequência de activação para um dos movimentos testados. Na oscilação postural e na rigidez do tornozelo foram também observadas diferenças entre os sujeitos bem como entre as posições realizadas. Conclusão. Concluiu-se que não sendo possível alterar a anatomia do bailarino, por vezes é possível intervir a nível funcional melhorando a capacidade técnica de forma obter um melhor desempenho e a actuar preventivamente em relação às lesões, uma vez que estas podem apresentar padrões cinéticos próprios, relacionados com a função muscular, a estabilidade postural e a rigidez articular.

Lumbo-pelvic stability and electromyography of abdominal muscles in ballet dancers

Evaluating the ability to rectify and maintain lumbar adjustment can contribute toward the understanding of the behavior of abdominal muscles and their participation in the stability of pelvic muscles in dancers during the posterior pelvic tilt and double straight leg lowering tests. Nine healthy volunteers (male and female ballet dancers; age mean: 25.9 ±7.37 years) underwent maximal isometric voluntary contraction (MIVC), isometric voluntary contraction at 50% of MIVC, posterior pelvic tilt (PPT) and double straight leg lowering (DSLL) tests. The tests were carried out in a single day, with 3 repetitions each. During the tests, electromygraphic signals of the rectus abdominis, obliquus internus and obliquus externus were recorded. The signal acquisition system was made up of bipolar surface electrodes, electrogoniometer and an electromechanic device (pressure sensor), which were connected to a signal conditioner module. Root mean square values of each muscle during the DSLL and PPT were converted into percentage of activation of 50% MIVC. Lower back pressure was submitted to the same process. ANOVA with repeated measures was performed, with the level of significance set at p < 0.05. The results revealed that all dancers were able to maintain posterior pelvic tilt and there was trend toward greater activation of the bilateral obliquus internus muscle. In an attempt to keep the pelvic region stabilized during DSLL, there was a greater contribution from the obliquus externus muscle in relation to other abdominal muscles.

Evaluation of movements of lower limbs in non-professional ballet dancers: Hip abduction and flexion

Background: The literature indicated that the majority of professional ballet dancers present static and active dynamic range of motion difference between left and right lower limbs, however, no previous study focused this difference in non-professional ballet dancers. In this study we aimed to evaluate active movements of the hip in non-professional classical dancers.Methods: We evaluated 10 non professional ballet dancers (16-23 years old). We measured the active range of motion and flexibility through Well Banks. We compared active range of motion between left and right sides (hip flexion and abduction) and performed correlation between active movements and flexibility.Results: There was a small difference between the right and left sides of the hip in relation to the movements of flexion and abduction, which suggest the dominant side of the subjects, however, there was no statistical significance. Bank of Wells test revealed statistical difference only between the 1st and the 3rd measurement. There was no correlation between the movements of the hip (abduction and flexion, right and left sides) with the three test measurements of the bank of Wells.Conclusion: There is no imbalance between the sides of the hip with respect to active abduction and flexion movements in non-professional ballet dancers. © 2011 Valenti et al; licensee BioMed Central Ltd.

Evaluation of movements of lower limbs in non-professional ballet dancers: hip abduction and flexion

Background The literature indicated that the majority of professional ballet dancers present static and active dynamic range of motion difference between left and right lower limbs, however, no previous study focused this difference in non-professional ballet dancers. In this study we aimed to evaluate active movements of the hip in non-professional classical dancers. Methods We evaluated 10 non professional ballet dancers (16-23 years old). We measured the active range of motion and flexibility through Well Banks. We compared active range of motion between left and right sides (hip flexion and abduction) and performed correlation between active movements and flexibility. Results There was a small difference between the right and left sides of the hip in relation to the movements of flexion and abduction, which suggest the dominant side of the subjects, however, there was no statistical significance. Bank of Wells test revealed statistical difference only between the 1st and the 3rd measurement. There was no correlation between the movements of the hip (abduction and flexion, right and left sides) with the three test measurements of the bank of Wells. Conclusion There is no imbalance between the sides of the hip with respect to active abduction and flexion movements in non-professional ballet dancers.

Musculoskeletal effects and injury risk in collegiate Indian classical and ballet dancers

Dancers of all forms often engage in aesthetic yet challenging movements. Their training, choreography, and performances require strength, stamina, flexibility, grace, passion, and emotion. Ballet and Bharatanatyam (an Indian classical dance form) dancers utilize two movements in each of their dance forms that are similar—a half-sitting pose and a full-sitting pose, both requiring external rotation of the legs and bending at the knee joints. The purpose of this study was to examine and compare the biomechanics of joint reaction forces and knee angles in both styles of dance for these particular poses. The study included nine female ballet dancers and seven female Bharatanatyam dancers. Hamstring and gastrocnemius flexibility were measured for each dancer. Knee angles, vertical peak forces, and moments were determined for dancers at the lowest point of their bending positions. Mann-Whitney U tests found significant differences in hamstring flexibility, right gastrocnemius flexibility, and knee angles for the full-sitting poses between ballet and Bharatanatyam dancers. No significant difference was found in the vertical peak forces as a ratio to total body weight and moments between the two styles of dance. Further research can be done to more directly assess a difference in injury risk between the ballet and Bharatanatyam dancers.

O ballet das lesões : associação entre agravos musculo-esqueleticos e aptidão fisica de praticantes de dança e de escolares

Universidade Estadual de Campinas . Faculdade de Educação Física

Use of a textured insole to improve the association between postural balance and ankle discrimination in young male and female dancers

A selvagem dança do corpo

Universidade Estadual de Campinas . Faculdade de Educação Física

Prevalência e fatores associados à dor em bailarinos profissionais

To investigate the prevalence and factors associated to painful symptomatology in professional ballet dancers. Methodos: An analytical transversal cut study was performed with 141 professional ballet dancers in the main capital cities of the Brazilian Northeast. McGill`s Pain Questionnaire and the Wisconsin Brief Pain Inventory, both validated for Portuguese, were used to assess painful symptomatology. Descriptive statistical analysis of the results was carried out, followed by Student`s t-test and Pearson s correlation with pvalue < 0.05. Results: High pain tolerance levels were observed in 70.2% of the subjects, where the intensity varied from moderate to severe. Pain in the lumbar region was present in 85.8% of the individuals. Positive correlations were verified between the degree of pain intensity and activities how to dance (60,3%), general activities (32,6%), sleep (28,4%), mood (27,7%), march (20,6%) and relations with others (16,3%). Conclusions: High pain prevalence was found in professional ballet dancers in the main capital cities of the northeast, and the most affected area was the lumbar followed by knees, neck, hip and feet, with substantial interference of pain symptoms in several activities of the personal and professional lives of these people

Dança, corpo e desenho: arte como sensação

Este trabalho busca refletir sobre o estatuto do corpo e do movimento nas artes a partir da noção de sensação, como empregada no pensamento do filósofo francês Gilles Deleuze. Tal propósito se fará a partir do singular encontro entre os trabalhos de um pintor/desenhista e um dos mais emblemáticos bailarinos clássicos. O corpo em movimento, quando atinge o estado de dança, não se reduz a uma forma, a uma representação, nem a uma mecânica. Antes, pelo contrário, sua leveza singular afeta-nos sobremaneira. Tal afecção será tomada como fio condutor de nossa análise, tendo em vista as diferentes sensações e expressões que pode suscitar. A sensação de um corpo que dança pode expressar-se na dança em si como também no desenho. Que relações esses diferentes meios de expressão do corpo dançarino podem estabelecer entre si? Que acontecimentos singulares podem emergir nesse encontro particular? Antes que forma, linhas de força e expressão. Corpo-vibração, torrente de afectos e perceptos, constituindo sensações que diferentes meios artísticos expressam diferentemente.

Use of sneaker rush and symptoms occurrence of skeletal muscle (SME) in Ballerina

Introduction: Technical literature shows high frequencies of injuries occurring in classical ballet dancers; however, only limited information about the permanent effects of chronic diseases are mentioned. Objective: To compare the presence of MSD among dancers who wear pointe shoes and those who do not. Methods: The research was conducted at the 27th Festival of Joinville in Santa Catarina. The study had the participation of 111 dancers, 88 of whom wore pointe shoes while 23 did not. Specific procedures were used to obtain information related to MSD and foot injuries caused by dancing. Results: The most affected parts were the knees (29.7% with pointe shoes versus 39% without), spine (26.4% with pointe shoes versus 22% without), and ankle/foot (20% with pointe shoes versus 12.2% without). Through odds ratio and respective confidence intervals (IC95%), the study identified protection factor in the knees (0.24; CI95% - 0.09-0.64) and legs (0.11; CI95% - 0.02-0.65) for dancers who wear pointe shoes. It was found that the risk of injuries in specific structures of the foot is significantly higher among those dancers. In this case, the appearance of bunions (9.74; CI95% - 1.25-75,99), calluses on the toes (3.46; CI95% - 1.29-9.27) and the association of the three (4.47; CI95% - 1.69-11.83) were those that showed an increased risk factor compared to dancers who do not stand en pointe. Conclusion: The use of pointe shoes in elite Brazilian dancers was associated to lower occurrence of MSD in the knee and leg, however it was strongly associated to foot injuries.

Relação entre postura, queixa dolorosa e lesão em bailarinas clássicas

Introduction: Due to the high recurrence of pain complaints and the increasing incidence of musculoskeletal injuries and postural changes in dance practice, researches related to this issue gained greater importance in scientific community. Objective: This study aimed to evaluate complaints and pain threshold, postural misalignments and the incidence of injuries in dancers noting if there is a relationship between these variables. Method: Participants were 15 ballet dancers in Marília - SP. We used photogrammetry for postural analysis, the McGill Pain Questionnaire for pain location of the volunteer, algometry pressure for measuring the threshold of pain perception and Referred Morbidity to verify and characterize the incidence of injuries this population. In the data analysis we use to percentage to quantify the data from questionnaires and Pearson correlation test angles of photogrammetry correlating with the values of the threshold of pain perception. Results: 73.33% of dancers reported to have suffered some kind of injury in the last year. The area of greatest pain complaint checked at McGill, was the region of the foot (73.30%). Conclusion: There was an agreement between regions of injury and pain, however, there wasn’t a correlation between the threshold of pain tolerance and postural angles.