Risk factors for musculoskeletal injury in elite pre-professional modern dancers: A prospective cohort prognostic study

Dancers Show More Accurate Trunk-Pelvic Joint Angle Reproduction While Wearing a Jacket Augmented With Elastic Bands

Purpose: The Backalast® compression jacket is intended to improve posture and proprioception of the trunk and shoulder girdle for dancers and dance students during dance training by way of elastic bands in the rear of the garment (which include bands enclosing the inferior thorax). This study was intended to investigate whether there is evidence to support those objectives. Materials and Methods: Fifteen dance students participated (4 male, mean age 19.9 ± 1.4 years old). The dependent variables of trunk-pelvis angle and proximity of trunk axis to global vertical for each participant were measured using optical motion capture before and after the completion of a series of trunk movements. The Helen Hayes model, which we used to represent the trunk, includes the shoulder girdles as part of the trunk. We compared the effect of the type of garment (Backalast® or control compression shirt) worn upon the 2 dependent variables, within-subject with paired t-tests. The order of whether Backalast® or control compression shirt was worn first was alternated between participants. Results: The pre/posttest difference in trunk proprioception as represented by the construct of ability to reproduce trunk-pelvis angle wearing the Backalast® was 0.8° ± 0.8°, but for the control shirt, the difference was 1.8° ± 1.4°, P = .03. The difference between garments in vertical trunk alignment, measured after the series of trunk movements, was not significant. Conclusion: Our findings suggest that the Backalast® can help enhance trunk proprioception when compared to the control compression shirt, although it did not change the angle at which the participants' held their trunks while standing erect (proximity to global vertical).

Preparation For Flight: The Physical Profile of Pre-Professional and Professional Circus Artists in the United States

Background

Established norms for fitness and performance measures are lacking in circus arts. These would assist healthcare professionals and coaches to screen for readiness to participate in training or performance, determine post-injury return to performance, and develop targeted conditioning programs.

Purpose

The purpose of this research was to establish norms for trunk and extremity physical exam and performance measures in circus artists by professional status, assigned sex at birth (ASAB), and age.

Study Design

Descriptive laboratory study.

Methods

Circus artists (n=201; ages 13-69y; 172 females ASAB, 29 males ASAB) from 10 cities across the United States underwent a baseline physical examination including shoulder, hip and trunk measures of passive (PROM) and active (AROM) range of motion, measures of flexibility (shoulder and hip), strength (manual muscle tests, grip strength), cardiovascular fitness (3 minute-step test), balance (single limb and handstand), and performance, (pull-ups, and the closed kinetic chain upper extremity stability test [CKCUEST]). ANOVAs were used to determine between group differences by age and T-tests to discern differences by ASAB or professional status.

Results

Differences existed by professional status for shoulder external rotation PROM, hip PROM, hip flexibility, shoulder and abdominal strength, and cardiovascular fitness. Sex differences were seen in active scapular upward rotation, hip and shoulder PROM and flexibility, hip and grip strength, and for functional performance measures (pull-ups, CKCUEST). Differences by age were limited to active scapular upward rotation, shoulder PROM, flexibility and strength, cardiovascular fitness, and balance. Overall, professionals outperformed pre-professionals for lower abdominal strength, pull-ups, handstand balance, cardiovascular fitness, hamstring, and straddle flexibility. Generally, males ASAB demonstrated greater shoulder flexibility and upper body functional strength while females ASAB had greater hip and lumbar flexibility and hip strength. No measures showed consistent declines with increasing age, though some showed differences between adolescents and adults.

Conclusion

These normative values for physical characteristics and functional performance in pre-professional and professional circus artists may be used to guide screening for readiness to participate in advanced training or performance, return to performance after injury, and the development of targeted strength and conditioning programs.

Level of Evidence

3.

Development and Feasibility of an Adolescent Dancer Screen

Background

Adolescent dancers are at high risk for injuries due to the physical demands of dance training and the physiological changes that occur during adolescence. Though studies report high injury rates, there are few standardized screening tools available for adolescent dancers.

Hypothesis/Purpose

To develop and describe a standardized, feasible, evidence-based, and clinically relevant screen for adolescent dancers.

Study Design

Descriptive Epidemiology Study.

Methods

Dancers at two suburban pre-professional dance studios, in two cohorts, participated in the Columbia Adolescent Dancer Screen (CADS) that includes dance injury history, health questionnaires (EAT-26, SF-36, DFOS), aerobic capacity, range of motion, strength, balance/orthopedic special tests, and dance technique. Participants were asked to complete a weekly injury surveillance questionnaire derived from the Dance-Specific Oslo Sports Trauma Research Centre Questionnaire on Health Problems for 14 weeks following the screening. Feasibility was assessed using process and content analysis in four areas: practicality, demand, implementation, and adaptation.

Results

Descriptive data were collected from 32 female dancers aged 11-17 with cohort one averaging 18.57 dance hours per week and cohort two averaging 10.6 dance hours per week. The screen was practical, able to screen seven to eight dancers per hour utilizing nine assessors and requiring a one-hour commitment from dancers. Cost and space requirements were considered and kept to a minimum while utilizing portable equipment. All screening slots were filled with all dancers agreeing to follow-up injury surveillance, indicating high demand. The screen was implemented with two cohorts with revisions to improve efficiency applied for the second cohort.

Conclusion

The CADS is a feasible screening tool for adolescent dancers that overcomes barriers by being pragmatic, evidence-based, and efficient. Screening can be implemented to obtain baseline values, inform wellness recommendations, and establish relationships with medical professionals.

Level of Evidence

Level 3b.

Prevalence and risk factors of musculoskeletal injuries in modern and contemporary dancers: a systematic review and meta-analysis

Background

A large number of studies have found that the musculoskeletal injury of modern and contemporary dancers has a high incidence. Previous publications have indicated that there are many potential factors that are related to dancing injury; however, they have not been proven, and even some data are conflicting in different research.

Results

The search yielded 18 prospective studies reporting on professional and pre-professional modern or contemporary dancers from companies and schools. The prevalence of modern and contemporary dancers was 0.82 (95% CI: 0.74~0.90). The injury proportion of trauma, overuse, ankle and foot, lower extremity, joint and ligaments, muscle and tendons, and time-loss were 0.40, 0.26, 0.49, 0.34, 0.33, and 0.29 in the total number of injuries. There was no evidence of a significant difference in sex, age, and education program. The factors of BMI and injury history achieved statistical significance, and the p-values were less than 0.01.

Conclusion

Based on the results of this article, BMI and injury history may be risk factors for injury in contemporary and modern dancers. Modern and contemporary dancers have a high prevalence of musculoskeletal injuries. Lower extremity injuries are the most common in the whole body, with injuries to the foot and ankle being more frequent. The mechanism of injury is mostly overuse injury, and the injured tissues are mostly muscle tendons and joint ligaments.

Relationships Between Common Preseason Screening Measures and Dance-Related Injuries in Preprofessional Ballet Dancers

OBJECTIVE: To examine modifiable and nonmodifiable factors for associations with dance-related injury among preprofessional ballet dancers over 5 academic years. DESIGN: Prospective cohort study. METHODS: Full-time preprofessional ballet dancers (n = 452; 399 female; median age [range], 15 years [11-21]) participated across 5 academic years at a vocational school. Participants completed baseline screening and online weekly injury questionnaires including dance exposure (hours/week). Zero-inflated Poisson regression models were used to examine associations between potential risk factors measured at baseline and self-reported dance-related injury. RESULTS: In count model coefficients, left one leg standing score (log coefficient estimate, -0.249 [95% CI: -0.478, -0.02]; P = .033) and right unipedal dynamic balance time (log coefficient estimate, -0.0294 [95% CI: -0.048, -0.01]; P>.001) carried a protective effect with increased years of training when adjusted for Athletic Coping Skills Inventory (ACSI) score. A significant association was found for left unipedal dynamic balance time and dance-related injury (log coefficient estimate, 0.013 [95% CI: 0.000, 0.026]; P = .045) when adjusted for years of training and ACSI score. There were no significant associations between dance-related injury and ankle and hip range of motion, active straight leg raise, or Y Balance Test measures. CONCLUSION: When adjusted for years of previous dance training and psychological coping skills, there was a significant association between limb-specific lumbopelvic control and dynamic balance tasks, as well as self-reported dance-related injury in preprofessional ballet. J Orthop Sports Phys Ther 2023;53(11):703-711. Epub 3 October 2023. doi:10.2519/jospt.2023.11835.

Injury epidemiology in Chinese undergraduate classical dance students: A 14-week prospective study

OBJECTIVES

The aim of this study was to investigate the injury prevalence, incidence rate, injury proportions, and characteristics of injuries in Chinese undergraduate classical dance students by using the modified Oslo Sports Trauma Research Centre Questionnaire on Health Problems.

DESIGN

Prospective study.

SETTING

Online survey.

PARTICIPANTS

63 Chinese classical undergraduate students (female: 40, male: 23; median age: 20 years, range: 17-20 years) completed the survey.

MAIN OUTCOME MEASURES

The injury prevalence (proportions) and incidence rate were calculated. The characteristics (severity, locations, injury type) of injuries were investigated.

RESULTS

During the 14-weeks, 84% students reported injury occurrence more than one time. The injury incidence rate was 3.28 injuries per 1000h across 14-weeks. Weekly proportion for all injuries ranged from 38.2% to 61.9% and substantial injuries ranged from 7.5% to 22.7%. The lower back was the most frequently injured body location (38.9%), followed by the knee (17.3%) and the ankle (12.9%). In all reported injuries, overuse injury was the most prevalent type (78.9%, 95% CI: 73.2%-81.1%).

CONCLUSIONS

Chinese classical dance students are at a relatively high risk for injuries. Injury prevention programs in Chinese classical dance students should focus on the lower back and lower extremity.

Injury Rates and Characteristics Associated with Participation in Organized Dance Education: A Systematic Review

INTRODUCTION

Several studies and recent systematic reviews have investigated injury in dance settings and have largely focused on specific concert dance genres (i.e., ballet, contemporary) and elite levels (i.e., pre-professional, professional) of dance. Less is known about the health of those who participate in dance education settings, namely teachers and students from private dance studios. Given that these individuals constitute a large proportion of the dance community, greater clarity of risks in the dance training environment could benefit an underserved majority by informing the development of effective injury prevention strategies.<br/> Objective: The primary objective was to describe injury rates and characteristics associated with participation in organized dance education settings.<br/> Methods: Six electronic databases were searched to April 2021 (Medline, EMBASE, SportDiscus, CINAHL, SCOPUS, Cochrane). Selected studies met a priori inclusion criteria that required original data from dance teacher and student samples within formal dance education settings. All genres of dance were eligible. Studies were excluded if no injury outcomes or estimates of dance exposure were reported, if injuries occurred during rehearsal and performance, or if dance was used as a therapeutic intervention or exercise. Two reviewers independently assessed each paper for inclusion at abstract and full text screening stages. The quality of included studies was assessed using the Joanna Briggs Institute Level of Evidence tool.<br/> Results: The initial database search identified 1,424 potentially relevant records, 26 were included and scored. Most studies (n = 22) focused on dance students only, three included only dance teachers, and one study included both. Among both dance students and teachers, the majority of injuries reported were overuse or chronic and involved the lower limb. For studies that reported injury rates (n = 14), estimates ranged from 0.8 to 4.7 injuries per 1,000 dance hours, 4.86 per 1,000 dancer-days, and 0.21 to 0.34 per 1,000 dance exposures.<br/> Conclusions: Based on the current research, dance students and teachers experience a similar rate of injury to concert and professional dancers, and their injuries are most commonly overuse injuries involving the lower extremity. There have been few high-quality investigations of injury specific to the dance training environment. Therefore, consensus around the burden of injury in the dance education settings remains difficult. Future dance epidemiological investigations that examine the burden of injury among dance teachers and students, include operational injury and exposure definitions, and utilize prospective designs are warranted.

Comparing Lumbar Lordosis in Functional Dance Positions in Collegiate Dancers With and Without Low Back Pain

Limited research has explored the relationship between lumbar lordosis and incidence of low back pain in dancers. The purpose of this study was to investigate the relationship between lumbar lordosis in functional dance positions and low back pain (LBP). Thirty full-time undergraduate ballet and modern collegiate dancers (28 female, 2 male) from three university dance programs participated in this study. Functional lumbar lordosis, hip passive range of motion, and core endurance were measured in a single session. Dancers participated in weekly follow-up surveys over a 4-month period to track the presence and severity of LBP. Primary analysis was performed using independent t-tests between groups who did and did not develop pain. Secondary analyses were performed using Pearson's r correlation. Eleven dancers reported no pain during the follow-up period, 16 reported pain, and three did not respond to follow-up surveys. Lumbar lordosis in right developpé á la seconde and right retiré was significantly greater (p < 0.05) in the group who reported pain compared to the group who reported no pain. Increased hold times in the supine bridge position was shown to be fairly correlated (p < 0.05) to reduced lumbar lordosis in first position (Pearson's r = 0.381), left retiré (Pearson's r = 0.396), and right developpé á la seconde (Pearson's r = 0.365). The results of this study suggest a relationship between increased lumbar lordosis in the retiré and developpé á la seconde dance positions and development of LBP. Increased endurance of posterior core musculature and gluteal muscles was inversely related to the magnitude of lumbar lordosis in some dance-specific positions. The measurement of lumbar lordosis during functional dance positions, particularly those requiring single leg stances, may help identify collegiate dancers with increased risk of developing low back pain.

Generalized Joint Hypermobility and Anxiety Are Serious Risk Factors for Dysfunctioning in Dance Students: A One-Year Follow-Up Study

Young professional dancers find themselves in a demanding environment. GJH within dancers is often seen as aesthetically beneficial and a sign of talent but was found to be potentially disabling. Moreover, high-performing adolescents and young adults (HPAA), in this specific lifespan, might be even more vulnerable to anxiety-related disability. Therefore, we examined the development of the association between the presence of Generalized Joint Hypermobility (GJH) and anxiety within HPAA with a one-year follow-up. In 52.3% of the HPAA, anxiety did not change significantly over time, whereas GJH was present in 28.7%. Fatigue increased significantly in all HPAA at one year follow-up (respectively, females MD (SD) 18(19), p < 0.001 and males MD (SD) 9(19), p < 0.05). A significantly lower odds ratio (ß (95% CI) 0.4 (0.2−0.9); p-value 0.039) for participating in the second assessment was present in HPAA with GJH and anxiety with a 55% dropout rate after one year. This confirms the segregation between GJH combined with anxiety and GJH alone. The fatigue levels of all HPAA increased significantly over time to a serious risk for sick leave and work disability. This study confirms the association between GJH and anxiety but especially emphasizes the disabling role of anxiety. Screening for anxiety is relevant in HPAA with GJH and might influence tailored interventions.

Prevalence and Risk Factors of Dance Injury During COVID-19: A Cross-Sectional Study From University Students in China

Objectives: Although coronavirus disease 2019 (COVID-19) has transformed the training environment of dancers worldwide, little is known on how this has affected injury prevalence, causes, and risk factors. Methods: An online investigation involving Chinese full-time dance students was conducted (September-November 2020), which covered two 6-month periods just before and during the first COVID-19 lockdown. Results: 2086 students (19 ± 2.4 years) responded to the investigation. Injury prevalence dropped from 39.6% (before the lockdown) to 16.5% (during the lockdown) (p < 0.01). It was noted that a significant increase in injury severity during the lockdown was caused due to a 4.1% increase in moderate-to-severe injuries (p < 0.05). During the lockdown, the injuries on the lower back, feet, and shoulders decreased significantly (p < 0.01), but the knee, ankle, and groin/hip joint injuries remained the same. Fatigue and the recurrence of an old injury remained as the top two perceived causes of an injury between the two periods with the increase in an unsuitable floor (p < 0.01), a cold environment (p < 0.05), and set/props (p < 0.05). The fatigue degree of students decreased (p < 0.01) and their hours of sleep increased (p < 0.01) during the lockdown. Binary Logistic Regression analysis indicated that dance injury is associated with fatigue, the hours of sleep, and the actions taken if they suspect an injury during the lockdown (p < 0.05), but is only related to the time set aside for a cooldown and age before the lockdown period (p < 0.05). Conclusion: Although injury prevalence dropped significantly during the first COVID-19 lockdown in Chinese dance students, the main dance injury characteristics remained the same. Decreased fatigue and longer hours of sleep could explain the aforementioned drop in injury prevalence during the lockdown.

Joint Hypermobility Does Not Increase the Risk of Developing Hip Pain, Cartilage Defects, or Retirement in Professional Ballet Dancers Over 5 years

OBJECTIVE

This study aimed to evaluate the risk of developing hip pain, cartilage defects, and retirement in hypermobile ballet dancers over 5 years.

DESIGN

Prospective cohort study.

SETTING

Professional Ballet Company.

PARTICIPANTS

Forty ballet dancers (57.5% women) were assessed at baseline and 21 dancers at 5 years.

INDEPENDENT VARIABLE

Baseline evaluation of generalised joint hypermobility (GJH) (GJH = Beighton score ≥5/9).

OUTCOME MEASURES

Cartilage defects on hip 3T magnetic resonance imaging and pain (the Copenhagen Hip and Groin Outcome Score: HAGOS) at baseline and follow-up, hip-related injury incidence, and retirement over 5 years.

RESULTS

Twelve dancers retired by follow-up, none due to hip injury or GJH. At baseline, 17 (42.5%) dancers were hypermobile, 18 (45%) had cartilage defects, and 15 (37.5%) reported hip pain (HAGOS pain <100). Cartilage defect prevalence was lower in GJH (n = 1) than non-GJH dancers (n = 17, P < 0.001). Beighton scores <5/9 were predictive of cartilage defect presence at baseline, independent of age and sex (P = 0.006). At follow-up, cartilage defects progressed in 2 dancers, one was hypermobile. Baseline and follow-up HAGOS pain scores were similar in GJH and non-GJH dancers (P > 0.05 for all). Hip-related injury over 5 years was reported by a similar number of GJH (n = 7) and non-GJH dancers (n = 6, P = 0.7). Hypermobility was more prevalent in active dancers (n = 12) than dancers who retired (n = 2), independent of age, rank, and sex (P = 0.03).

CONCLUSIONS

Hypermobile dancers are at no greater risk of reporting hip pain and injury or retirement over 5 years, and cartilage defect prevalence was much lower in GJH than non-GJH dancers.

Association between pre-participation characteristics and risk of injury amongst pre-professional dancers

STUDY DESIGN

Prospective Cohort Study.

BACKGROUND

Few investigations utilize evidence-informed pre-participation evaluation, inclusive injury definitions, and prospective surveillance to identify risk factors for dance-related injuries.

OBJECTIVE

To evaluate pre-participation characteristics that may be associated with greater odds of dance-related musculoskeletal complaints in pre-professional dancers.

METHODS

Full-time pre-professional ballet [n = 85, 77 females, median (range) age 15-years (11-19)] and contemporary [n = 60, 58 females, 19-years (17-30)] dancers underwent pre-participation evaluation: baseline questionnaire, coping skills, body mass index, bone mineral density, ankle range-of-motion, active standing turnout, lumbopelvic control, and balance tests. Self-reported complaints (any physical problem making dance participation difficult, irrespective of medical attention or time-loss) were captured weekly via online questionnaires for one academic year. Self-reported musculoskeletal complaints were recorded weekly (yes/no). Potential risk factors were identified a-priori through systematic review. Associations between potential risk factors and musculoskeletal complaints were examined with generalized linear mixed method regression models.

RESULTS

Response rate was 99%, with 81% of dancers reporting at least one musculoskeletal complaint. Of 1521 complaints (19% first-time, 81% ongoing), the ankle (22%), knee (21%), and foot (12%) accounted for the majority. Injury history [odds ratio (OR) 7.37 (95% CI 3.41, 15.91)] and previous week's dance hours [OR 1.02 (1.01, 1.03)] were associated with dance-related musculoskeletal complaints.

CONCLUSIONS

Prevalence of musculoskeletal complaints amongst pre-professional dancers is high and associated with injury history and training volume. Further understanding of the relationship between training load and injury is needed, with particular consideration of the dynamic and recursive nature of dance injury etiology.

LEVEL OF EVIDENCE

Therapy / Prevention, Aetiology / Harm, level 2b.

Effectiveness of physiotherapy interventions for injury in ballet dancers: A systematic review

Background

The unique repetitive nature of ballet dancing, which often involves transgressing endurance limits of anatomical structures, makes dancers prone to injury. The following systematic review aims to assess the effectiveness of physiotherapy interventions in the treatment of injuries in ballet dancers.

Methods

The review was performed in line with the PRISMA statement on preferred reporting items for systematic reviews and meta-analyses. Six electronic databases (PubMed, Ovid Embase, Cochrane, Medline, PEDro, Google Scholar) were queried. The study populations comprised active ballet dancers and/or ballet school attendees with acute and chronic injuries and those with persistent pain. There were no restrictions regarding age, sex, ethnicity or nationality. The Modified McMaster Critical Review Form for quantitative studies was used to assess the methodological quality of the studies reviewed in accordance with the relevant guidelines.

Results

Out of the total of 687 articles subjected to the review, 10 met the inclusion criteria. Diverse physiotherapeutic interventions were described and effectiveness was assessed using different parameters and measurements. Overall, the results indicate that physiotherapy interventions in ballet dancers exert a positive effect on a number of indices, including pain, ROM and functional status.

Conclusions

Due to the small amount of evidence confirming the effectiveness of physiotherapeutic interventions in ballet dancers after injuries and methodological uncertainties, it is recommended to improve the quality of prospective studies.

Incidence and prediction of ankle injury risk: a prospective cohort study on 91 contemporary preprofessional dancers

Objectives

This study examines the incidence of ankle injuries and identifies ankle injury risk among contemporary preprofessional dancers.

Methods

A total of 91 first-year contemporary preprofessional dancers were prospectively followed during one academic year. Self-reported ankle injuries, assessed with the Oslo Sports Trauma Research Centre questionnaire, were categorised as all complaint ankle injuries, substantial ankle injuries or time-loss ankle injuries. In addition, ankle injuries leading to medical attention were included. Regression analyses were used to determine the association between potential risk factors (dancer characteristics, history of ankle injury in the previous year, ankle range of motion and dorsiflexion) and ankle injuries.

Results

The 1-year ankle injury incidence proportion was 18.7% (n=17), 8.8% (n=8), 15.4% (n=14) and 7.7% (n=7), respectively, for all complaint ankle injuries, ankle injuries requiring medical attention, time-loss injuries and substantial injuries. Being male (OR=0.27; 95% CI 0.09 to 0.75) and being a student of the Bachelors in Dance and Education (OR=0.27; 95% CI 0.08 to 0.97) were univariately associated with a lower risk of an ankle injury.

Conclusion

Almost 20% of first-year preprofessional dancers reported an ankle injury, with more than 80% of the dancers reporting that their injury leads to dance time loss. Males and students of the bachelors in dance and education were at lower risk of ankle injuries. As ankle injuries are common among dancers, studies with larger sample sizes, a more heterogeneous population (eg, different dance styles) and longer follow-up periods are necessary to evaluate the impact of ankle injuries in further detail.

Generalized Joint Hypermobility and Injuries: A Prospective Cohort Study of 185 Pre-Professional Contemporary Dancers

Generalized joint hypermobility (GJH) has been mentioned as one of the factors associated with dance injuries, but the findings are inconclusive. This study aims to investigate whether GJH, based on different Beighton score cut-off points, is a potential risk factor for injuries in pre-professional dancers. Four cohorts of first-year pre-professional dancers (N = 185), mean age 19.1 ± 1.3 years, were screened on musculoskeletal functioning at the start of their academic year. The Beighton score was used to measure GJH. During the academic year, the dancers completed monthly questionnaires about their physical and mental health. Based on the Oslo Sports Trauma Research Centre Questionnaire on Health Problems (OSTRC), three injury definitions were used (i.e., all complaints, substantial injury, and time-loss injury). To examine potential risk factors for injuries, univariate and multivariate regression models were applied. The response rate of monthly completed questionnaires was 90%. The overall mean (SD) Beighton score was 2.8. The 1-year injury incidence proportion was 67.6% (n = 125), 43.2% (n = 80), and 54.6% (n = 101) for all complaint injuries, substantial injuries, and time-loss injuries, respectively. The multivariate analyses showed a significant association between a previous long lasting injury in the past year and the three injury definitions (p < 0.05). Pre-professional contemporary dancers are at high risk for injuries and hypermobility. However, these two variables are not associated with each other. Health professionals should take injury history into account when assessing dance students, because this variable is associated with increased injury risk.

Injury Occurrence in Modern and Hip-Hop Dancers: A Systematic Literature Review

Introduction

Dance-related injuries have become a field of great interest to researchers, with the most commonly reported injuries being those sustained by ballet dancers. However, there is a lack of research into injuries sustained by those who perform modern and hip-hop dance.

Methods

A systematic literature review using the MEDLINE research database was performed and a search carried out for full-text studies that investigate injuries in modern and hip-hop dance.

Results

While a total of 74 hits were obtained from various searches, only nine studies were included in the systematic literature review. Six of them examined modern dancers, two examined break dancers and one examined hip-hop dancers. The results show that hip-hop dancers (and especially break dancers) sustain more injuries in comparison to modern dancers. The most common injuries are in the lower extremities, with studies revealing that overuse injuries occur in up to 71% of cases.

Conclusions

The injury incidence rate in hip-hop dance seems to be higher compared to modern dance, chiefly because of the more demanding biomechanics involved and the dance techniques employed. Prevention management can have a positive effect on the number of injuries.

Injuries across a pre-professional ballet and contemporary dance tertiary training program: A retrospective cohort study

OBJECTIVES

The study aims to analyse the incidence of medical attention injuries, subsequent injuries, and the median time to injury, across tertiary ballet and contemporary dance training programs.

DESIGN

Retrospective cohort.

METHODS

Consenting ballet and contemporary dance students completing the third/final year of two tertiary programs were included. The three-year programs consisted of six semesters. Access was granted to onsite physiotherapy notes, timetables, and academic enrolment. Injury was defined as requiring medical attention. Injury and exposure data were extracted, injuries coded for location and tissue, and subsequent injuries, occurring after an initial index injury, categorised. Mean, standard deviation, range, injury incidence, risk and rate ratios, proportions and Kaplan-Meier curves were calculated to report participant characteristics, and injury patterns across three years of the dance program.

RESULTS

All 17 students (mean age=20.7 years; standard deviation=1.32) from one program consented to participate, of which all were injured across the three-year program, with 2.71 (95% confidence interval: 2.22, 3.20) injury incidence rate per 1000h, and increasing injury incidences seen across the program. The most injured site and tissue were the ankle (17.65%) and muscle (23.53%) respectively. 74.86% of subsequent injuries were different (affecting a different location and tissue), and 4.88% reinjuries (affecting the same location, tissue, and structure after recovery). The median time to the first injury was seven weeks in the first semester, and later in subsequent year levels.

CONCLUSIONS

Increasing injury incidences were seen across the program. Most subsequent injuries were different from previous injuries in this cohort. Future research should use exposure measures beyond hours (i.e. intensity) and consider subsequent injuries.

Hamstring extensibility differences among elite adolescent and young dancers of different dance styles and non-dancers

Background

Hamstrings have been analyzed extensively due to their tendency to shorten and their effect in the lumbo-pelvic dynamics and the sagittal position of the spine in trunk flexion with extended knees positions. It has been demonstrated that practicing a certain sport results in long-term changes in hamstring extensibility. Despite this, adequate extensibility of the hamstring musculature is essential for the dancer’s performance. Several studies have found differences in the extensibility of the hamstrings depending on the dance style, but none have compared ballet, Spanish dance and modern dance. The purpose of the present research was to analyze the differences in hamstring extensibility among professional dance students based on dance style practiced and non-dancers.

Methods

The sample was comprised of 210 students from the Professional Dance Conservatory (70 for ballet, 70 for Spanish dance and 70 for modern dance) and 70 non-dancers. For the assessment of hamstring extensibility, the angle in the passive and active straight leg raise (PSLR and ASLR, respectively) test, and the scores of the pelvic tilt in sit-and-reach (SR) test and the toe-touch (TT) test were randomly conducted.

Results

The results showed significant differences for all the tests according to group (p < 0.001). In the PSLR and ASLR test, for both legs, and in the pelvic tilt in the SR test, the ballet dancers showed greater ranges of hamstring extensibility than the modern dancers and Spanish dancers (p ≤ 0.001). In the distance in the SR test and in the pelvic tilt in the TT test, the ballet dancers obtained higher values than the Spanish dancers (p = 0.004 and p = 0.003, respectively). The modern dancers showed higher ranges of hip flexion than the Spanish dancers in the ASLR test for both legs and in the pelvic tilt in the SR test (p from 0.007 to <0.001). Dancers showed significantly higher hamstring extensibility than non-dancers in all the tests (p < 0.001).

Conclusions

The systematic practice of dance, regardless of the style, seems to lead to high ranges of hamstring extensibility. Ballet dancers have the greatest hamstring extensibility.

Can young dancers skip/recover from patellofemoral pain? A two-year follow-up

Aiming to follow the prevalence of patellofemoral pain (PFP) among young dancers over 2-years, and to assess the prevalence of re-injured/recovered dancers; 67 dancers (aged 12.8 ± 0.5) were screened for PFP at baseline, 65 dancers at 1^st follow-up and 51 dancers at 2^nd follow-up. All dancers (46) that took part in all the 3 screenings had at least one episode of PFP along the screenings. No dancers recovered in the 1^st follow-up, yet 40.5% of the dancers with PFP at the 1^st follow-up recovered in the 2^nd follow-up. Along the 3 screenings, 23.9%, 34.8%, and 41.3% of the dancers had 1,2 or 3 PFP episodes, respectively. None of the dancers skipped PFP along the 3 screenings. A high prevalence of dancers had sustained PFP along the 2 follow-ups, with low recovery rate. Dancers and teachers should be alert to the need for devising modifications of training and injury prevention strategies from young age.

The relationship between the functional movement screen, star excursion balance test and the Beighton score in dancers

Objectives: To determine the association between the Functional Movement Screen (FMS), Star Excursion Balance Test (SEBT) and the Beighton Score (BS) in dancers with implications for performance and injury.Methods: The study was of cross-sectional design and included 47 female university dancers (age: 20.4 ± 0.7 years, height: 160.5 ± 5.8 cm; mass: 55.6 ± 4.8 kg). Participants completed the FMS and the anterior, posteromedial and posterolateral reach components of the SEBT and hypermobility was assessed via the BS.Results: A fair significant correlation existed between FMS composite and total BS (r = 0.37, p = 0.01). For individual elements of the screening tools, there were 24 significant correlations between the FMS and the BS, 11 significant correlations between the FMS and SEBT and 4 significant correlations between the SEBT and BS.Conclusion: The FMS and the BS correlations highlighted the importance of the deep squat in functional movement and the relationship between FMS mobility elements and the BS. The significant correlation between the FMS and the BS may suggest that they capture similar information. The active straight leg raise and shoulder mobility measurements should be considered key elements to measure during screening.

Joint Hypermobility as a Predictor of Mechanical Loading in Dancers

CONTEXT

Dance requires the performance of complex movements that may exceed normal anatomical range. However, in hypermobile individuals, this may have implications for injury and performance.

OBJECTIVES

The aim of the study was to investigate the efficacy of the Beighton score (BS) in predicting mechanical loading in dancers in hypermobile and nonhypermobile dancers with consideration of accelerometer placement and lumbar flexion hypermobility.

DESIGN

Cohort study, clinical measurement.

SETTING

University.

PARTICIPANTS

A total of 34 dancers had their joint hypermobility assessed by the BS. Participants completed the Dance Aerobic Fitness Test with a global positioning device incorporating a triaxial accelerometer located at the cervico-thoracic junction (C7) and one at the midbelly of the gastrocnemius.

MAIN OUTCOME MEASURES

Accelerometry data were used to calculate PlayerLoad total, PlayerLoad medial-lateral, PlayerLoad anterior-posterior, and PlayerLoad vertical. Physiological response was measured via heart rate and fatigue response by rate of perceived exertion.

RESULTS

The total BS was a poor predictor of all mechanical loading directions with PlayerLoad anterior-posterior C7 (r = .15) and PlayerLoad total lower limb (r = .20) the highest values. Multiple linear regression was a better predictor with values of C7 (r = .43) and lower limb (r = .37). No significant difference existed between hypermobile and nonhypermobile subjects for mechanical loading values for all stages of the Dance Aerobic Fitness Test and for heart rate and fatigue responses.

CONCLUSIONS

The BS is not a good predictor of mechanical loading which is similar in hypermobile and nonhypermobile dancers for all levels of the Dance Aerobic Fitness Test. Mechanical loading and fatigue responses are similar between hypermobile and nonhypermobile dancers.

The Beighton Score and Injury in Dancers: A Prospective Cohort Study

CONTEXT

Joint hypermobility has a high prevalence in dancers and may be associated with injury and performance.

OBJECTIVES

To investigate whether total Beighton score can predict injury and to determine the relationship between joint hypermobility and injury, and to report injury demographics.

DESIGN

A prospective cohort injury study.

SETTING

Edge Hill University dance injury clinic.

PARTICIPANTS

Eighty-two dancers (62 females, 20 males).

MAIN OUTCOME MEASURES

Joint hypermobility via the Beighton score ≥4 with lumbar flexion included and removed.

RESULTS

A total of 61 dancers were classified as hypermobile, which was reduced to 50 dancers with lumbar flexion removed. A significant difference existed between pooled total days injured in hypermobile dancers and nonhypermobile dancers with lumbar flexion included (P = .02) and removed (P = .03). No significant differences existed for total Beighton score between injured and noninjured groups with lumbar flexion included (P = .11) and removed (P = .13). Total Beighton score was a weak predictor of total days injured (r2 = .06, P = .51). In total, 47 injuries occurred in 34 dancers, and pooled injury rate was 1.03 injuries/1000 hours. Receiver operating characteristic curve analysis demonstrated an area under the curve of 0.83 for male dancers with lumbar flexion removed, which was considered diagnostic for injury.

CONCLUSIONS

The Beighton score can be utilized to identify dancers who may develop injury. Clinicians should consider the role of lumbar flexion in total Beighton score when identifying those dancers at risk of injury. Different injury thresholds in female and male dancers may aid injury management.

Ankle Injuries in Dancers

The term dance encompasses a broad range of different styles; much of the orthopaedic literature has focused on ballet dancers. Injury is common in dancers at all levels, and many serious dancers sustain multiple injuries as they progress through their career. Foot and ankle injuries are among the most common injuries experienced by dancers. These injuries include those that are specific to dancers because of the unique physical maneuvers required to effectively perform, but they can also include common injuries that may require relatively different treatment because of the physical demands of the dancer. Os trigonum syndrome and flexor hallucis longus tenosynovitis generally fall into the former category as they are injuries that are more prevalent in dancers due to the extreme plantarflexion involved in dancing, especially ballet, and the relative demand placed on the toe flexors, most notably the flexor hallucis longus. On the other hand, anterior ankle impingement occurs both in dancers and in the general public. In many cases, a team approach to treatment with knowledgeable physical therapists can obviate the need for surgical treatment. If surgical treatment proves necessary, good results can be achieved with sound surgical technique and a well thought-out rehabilitation program.

Characteristics of Contact Force and Muscle Activation During Choreographed Falls With 2 Common Landing Techniques in Contemporary Dance

This study investigated the contact forces and muscle activation during 2 choreographed fall techniques in contemporary dancers and how these were affected by the fall technique. Ten collegiate-level dancers were instructed in 2 choreographed falls: (1) an anteriorly focused fall involving ankle plantar flexion, knee flexion, and hip flexion with dispersion of forces up the anterior surface of the shank (technique 1) and (2) a laterally focused fall involving inversion at the ankle with dispersion of forces up the lateral aspect of the shank (technique 2). The knee and hip contact forces were 26.3% smaller (technique 1: 1743 N vs technique 2: 1284 N) and 24.1% greater (technique 1: 1334 N vs technique 2: 1656 N), respectively, in technique 2 (P < .03). At the time of knee contact, percentage of maximal voluntary isometric contraction (%MVIC) was 45.8% greater for rectus femoris muscle (technique 1: 7.2% vs technique 2: 10.5%) and 96.9% greater for gluteus medius muscle (technique 1: 3.2% vs technique 2: 6.3%) (P < .01) in technique 2. The results provide insight into determining safer landing strategies to avoid knee injuries in individuals who experience a fall (ie, dancers, athletes, and older adults).

Dance Functional Outcome Survey: Development and Preliminary Analyses

The Dance Functional Outcome Survey (DFOS) was developed as a self-report questionnaire for healthy and injured ballet and modern dancers, focusing on the low back and lower extremities. Our aim was to determine factor analysis and internal consistency of the 16 items and to investigate test-retest and equivalence reliability and validity of the DFOS compared to three orthopedic outcomes instruments. Data were collected from 80 healthy and injured adult ballet and modern pre-professional and professional dancers. DFOS Likert-type and visual analog scales were completed twice within 4-9 days to study test-retest reliability. The Cincinnati Knee Rating System, Olerud and Molander Foot-Ankle Questionnaire, and Oswestry Disability Index were used to assess concurrent validity using intraclass correlation coefficients in SPSS, p<0.05. To determine instrument dimensions and internal consistency of the items, we conducted exploratory factor analysis and calculated Cronbach's α in JASP. DFOS demonstrated single factor loading and high Cronbach's α; high test-retest repeatability and equivalence reliability ( r =0.74-0.99) and acceptable criterion validity compared to the orthopedic outcomes instruments (r≥0.67). These results support further study of a revised 14 item Likert-version DFOS for repeatability, validity and responsiveness.

Dance exposure, wellbeing and injury in collegiate Irish and contemporary dancers: A prospective study

OBJECTIVES

Dance exposure and determinants of wellness in Irish dance (ID) and contemporary dance (CD) are under-investigated in pre-professional, collegiate cohorts. This study prospectively investigated these variables in ID and CD participants for one year.

DESIGN

Prospective study.

SETTING

University-level institutes of dance, United Kingdom (UK) and Ireland.

PARTICIPANTS

Fifty (ID = 21, CD = 29) full time students of dance at Trinity Laban Conservatoire of Music and Dance, (UK) and the University of Limerick, Ireland.

MAIN OUTCOME MEASURES

Weekly hours of dance, general health, sleep quality, injury defined as "any pain or injury that impacted upon their ability to dance".

RESULTS

Dance exposure varied considerably for both genres across the year. CD participants danced for more hours weekly (p < 0.001). Overall injury incidence (time-loss and non-time-loss) was 10.6 and 8.4 injuries per 1000 h dancing for ID and CD groups respectively. 70.4% of injuries were non-time-loss. Better sleep (p = 0.007) and general health (p < 0.001) scores were negatively correlated with days lost/impacted by injury. CD participants reported a significantly higher dance exposure in the week prior to a time-loss injury than during the previous four weeks (p = 0.044).

CONCLUSIONS

Dance exposure is erratic in these cohorts with dancers frequently performing when injured. Poor sleep, general health, and increased dance exposure may be associated with injury.