Ballet dancer's turnout and its relationship to self-reported injury

Cueing Dancers to "Externally Rotate From the Hips" Improves Potentially Injurious Ankle Joint Angles and Contact Forces During a Demipointe Ballet Position

Introduction: The demipointe dance position puts the ankle at high risk of overuse injury and posteromedial ankle pain due to increased ankle valgus forces. Previous work has shown that creating lower limb external rotation intrinsic to demipointe with hip external rotation reduces foot pronation that causes ankle valgus stress. Therefore, the purpose of this work was to examine long axis rotation kinematics of the hip, knee, and ankle as well as the ankle joint contact forces in demipointe to better understand the biomechanical impact(s) of the specific cue to increase hip external rotation in this position. Methods: Three-dimensional motion capture and force plate data were collected from 23 contemporary or ballet pre-professional dancers (age: 19.94 ± 1.34 years) who each performed 3 dancer-selected (DS) demipointe positions and 3 demipointes with the cue to "externally rotate from the hips." Results: The cue to increase hip external rotation resulted in significantly increased hip external rotation angle [DS: 37.5; 9.42° (median; interquartile range), Cued: 39.9; 10.8°, P < .0001)] and significantly reduced ankle eversion angle (DS: 8.13; 11.4°, Cued: 7.77; 10.3°, P = .023). However, total turnout angle was also significantly decreased (DS: 75.8; 7.91°, Cued: 75.4; 7.73°, P < .0001), which is undesirable for proper esthetic performance of demipointe. Total ankle joint force remained unchanged, but ankle eversion force was significantly reduced (DS: 15.3; 4.18 %bodyweight (BW), Cued: 14.7; 4.99 %BW, P < .0001) with use of the cue. Discussion/Conclusion: Utilization of a cue to increase hip external rotation was successful in increasing hip contribution to turnout angle and reducing injurious ankle eversion force. Further coaching using this cue may allow dancers to produce these advantageous mechanics while maintaining turnout angle.

Hip Range of Motion and Strength in Young Pre-Professionals Ballet Dancers Versus Non-Dancers

Introduction: Lower-extremity external rotation, commonly known as turnout, is a fundamental skill in dance. Limited data exist regarding joint range of motion and strength in pre-professional young dancers and non-dancers. This study aimed to evaluate the differences in hip range of motion and hip strength between pre-professional ballet dancers and non-dancers. Additionally, the study assessed the variations between the left and right sides within each group. Methods: This observational study assessed 60 pre-professional ballet dancers and 31 non-dancers with an average age of 11.91 ± 1.49. Evaluation included passive hip rotation, tibial torsion, total passive turnout measured with digital goniometers, and total active turnout (both static and dynamic) through standing on paper and rotational discs. Hip rotation strength was measured using a force sensor device. Statistical analyses encompassed student t-tests, Pearson's correlations, and ANCOVA with age and body weight as covariates, applying the Bonferroni correction for multiple comparisons. Results: Ballet dancers exhibited greater passive hip external rotation and lower passive hip internal rotation compared to non-dancers. They also demonstrated superior total active turnout (static and dynamic). After adjusting for age and weight, dancers demonstrated significantly higher hip external rotation strength than non-dancers. Hip internal rotation strength did not differ significantly between the groups. Ballet dancers displayed inherent asymmetry, with the left side showing greater tibial torsion and standing active turnout, while the right side exhibited greater hip external rotation during dynamic active turnout. Non-dancers did not show significant side differences. Conclusions: Young pre-professional ballet dancers exhibited significant hip rotation differences compared to non-dancers, including notable right-left asymmetry. These findings should be considered when planning training, aiming to optimize musculoskeletal attributes and promote balanced hip rotation. Recognizing these asymmetries and addressing muscular imbalances is vital for injury prevention and performance enhancement.

Peripheral nerve injuries in the performing artist

Dancers and musicians have unique physical demands that can lead to injury of the peripheral nerves. Specific dance movements and specific instrument positions, combined with countless hours of practice and repetition, create an environment for potential nerve injury. Familiarity with these variables and recognition of the common presentations of neuropathic syndromes are essential in the evaluation of a performing artist with a suspected peripheral nerve injury. Assessment should include an understanding and analysis of their dance style or instrument playing posture, particularly in the position or motion that recreates the symptoms if possible. Practice and performance schedules should also be considered. Diagnosis may require electrodiagnostic testing, imaging, or diagnostic injections. Treatment should be comprehensive and may include modifications in practice schedule, posture/position, and technique in addition to consideration of medications, splints/orthoses, physical therapy, and injections. The instructor/teacher should be involved in the treatment plan if applicable. Complete rest in this population may not be realistic or necessary. Early and accurate diagnosis of nerve injury is important for safe return to dance or instrumental music.

The vertical mobility of the first tarsometatarsal joint during demi-plié with forced turnout in ballet dancers

The forced turnout has a perceived risk of development of hallux valgus (HV) in ballet dancers. We determined how the forced turnout affects the sagittal mobility of the first tarsometatarsal (TMT) joint, which is one of the pathogenic factors of HV development. Seventeen female ballet dancers (body mass index: 18.2 ± 1.8 kg/m2) were included and performed demi-plié in control, functional turnout, and forced turnout conditions. Ultrasound imaging synchronized with a three-dimensional motion analysis system was used for measuring the vertical locations of the first metatarsal and medial cuneiform (MC) to evaluate the first TMT joint mobility. Plantar displacement of MC and the first TMT joint mobility in the forced turnout were the greatest among the 3 conditions. Multiple regression analysis indicated that the greater extent of the forcing angle might increase the displacement of MC and the first TMT joint mobility. Evaluating the sagittal mobility of the first TMT joint in the forced turnout can assist in understanding the association between inappropriate techniques including the forced turnout and HV development in ballet dancers. Since the excessive mobility of the first TMT joint is a factor in HV development, the acquirement of adequate active turnout may have the potential to prevent HV development in ballet dancers.

[Dance-specific eligibility of vocational ballet students - examinations at a governmental training institution for classical ballet]

BACKGROUND

During their training, pre-professional ballet students are confronted with physical stresses comparable to those of competitive sports. In competitive sports, there are mandatory and binding aptitude tests to ensure that the growing athlete meets the requirements. In ballet, there are no such mandatory examinations preceding the start of training. For adult professional dancers, musculoskeletal ideals could be isolated from the dance medicine literature. However, only a few studies describe musculoskeletal characteristics of pre-professional ballet students. It is neither known at what age a student should meet the ideal measurements for an adult nor what deviations from the ideal can be considered normal. This study aims to describe sociodemographic and musculoskeletal characteristics of pre-professional ballet students and discusses to what extent they already meet or deviate from dance-specific eligibility criteria for adult professional ballet dancers.

MATERIAL AND METHODS

In this study, n = 414 female and n = 192 male students of John Cranko School (JCS) were seen by an experienced orthopaedist and dance physician. Mean age was 13.9 years (SD 3.5, range 5-22 years). Their medical history was taken (age; nationality; start of ballet/training) and a physical examination was performed (height/weight; symmetry of shoulder girdle, spine, waist triangles; pelvic tilt; tibial torsion; range of motion of base of index finger joint, spine, hips, ankle and base of great toe joint). Subsequently, the results of this study were compared with suitability criteria for adult professional ballet dancers that had been isolated from the dance medicine literature for a previous article.

RESULTS

Examinees were from 49 different nations. 34.6% of the female subjects (≥16 years) were between 165 and 170 cm and 33.3% of the male subjects (≥18 years) were between 178 and 185 cm tall. 45.0% of those examined showed low body weight (<10th percentile, BMI <18.5 kg/m²). The trunk of 61.0-84.8% of those examined was erect and symmetrical. 25.2% had scoliosis. Half (53.5%) were found to have a bilateral external rotation of the hips of at least 60°, and 68.7% had a bilateral internal rotation between 20 and 50°. 87.3% exhibited a bilateral tibial torsion between 15 and 40°. A bilateral en dehors of 90° was calculated for 25.0%. In 9.1% of those examined, the upper ankle joints presented a dorsiflexion of at least 25°, and in 70.2%, a plantarflexion of at least 70° was seen. In 88.0%, the metatarsophalangeal joint of the great toe was 90° (f) and 80° (m) on both sides.

CONCLUSION

The results of this study showed that pre-professional ballet students fulfil many characteristics of adult professional ballet dancers. High values already among young age groups suggest a ballet-specific selection. Nevertheless, not all students fulfil the theoretical "ideal measurements" for professional classical ballet. These anatomical limits should be considered individually in training to protect the growing pre-professional ballet dancer. The high ballet-specific anatomical demands, but especially the large number of students with a low body weight, underline the necessity of mandatory aptitude tests at the beginning and regular check-ups in the course of training to avert compensatory mechanisms and their consequential damage and to screen for eating disorders and disorders of eating behaviour.

Excessive Femoral Anteversion Leading to Symptomatic Posterior Femoroacetabular Impingement, Cam Deformity of the Posterior Femoral Head-Neck Junction, and Anterior Hip Instability in a Dancer: A Case Report

CASE

An adolescent female dancer with excessive femoral anteversion presented with posterior and anterior hip pain aggravated by poses that required extension and external rotation. Imaging revealed an atypical cam deformity of the posterior head-neck junction. During surgery, the posterior head-neck junction was observed to impinge on the posterior acetabulum with anterior subluxation of the hip. After a derotational femoral osteotomy, the patient experienced resolution of her symptoms.

CONCLUSION

Excessive femoral anteversion can lead to reactive cam deformity, posterior intra-articular impingement, and anterior hip instability in patients who require repetitive hip extension and external rotation, such as ballet dancers.

Association of Proximal and Distal Factors With Lower Limb Kinematics During a Classical Ballet Jump

CONTEXT

Excessive dynamic lower limb misalignment may predispose ballet dancers to jump-related injuries. However, it is unknown whether proximal and distal factors influence this movement pattern. The aim of this study was to investigate whether hip abduction strength, foot alignment, and ankle dorsiflexion range of motion (ROM) are associated with peak angles of hip adduction and internal rotation and knee abduction during the preparation and landing phases of a classical ballet jump.

DESIGN

Cross-sectional study.

METHODS

Forty-one healthy amateur ballet dancers were included. Hip abduction strength was evaluated isometrically using a handheld dynamometer, foot alignment was determined by the shank-forefoot alignment, and weight-bearing ankle dorsiflexion ROM was measured by performing the lunge test. Peak hip and knee angles were analyzed 3-dimensionally during the preparation and landing phases of a single-leg jump. A Pearson correlation matrix was used to investigate the association of hip abduction strength, shank-forefoot alignment, and ankle dorsiflexion ROM with peak angles of hip adduction and internal rotation and knee abduction during the preparation and landing phases of the jump.

RESULTS

Greater hip abduction strength was associated with greater peak hip internal rotation angle (r = .43, P < .05), but not with peak hip adduction and knee abduction angles during the preparation phase of the jump. There were no associations of shank-forefoot alignment and ankle dorsiflexion ROM with peak hip and knee angles during the preparation (r = -.23 to .36, P > .05) and landing (r = -.20 to .24, P > .05) phases of the jump. There was no association of hip abduction strength with peak hip and knee angles during the landing phase of the jump (r = -.28 to .16, P > .05).

CONCLUSION

Hip abductors strengthening, correction of foot misalignments, and increasing ankle dorsiflexion ROM may not prevent excessive hip and knee movements during a classical ballet single-leg jump in amateur dancers.

Epidemiological Characteristics of Foot and Ankle Injuries in 2 Professional Ballet Companies: A 3-Season Cohort Study of 588 Medical Attention Injuries and 255 Time-Loss Injuries

Background

The foot and ankle are often reported as the most common sites of injury in professional ballet dancers; however, epidemiological research focusing on foot and ankle injuries in isolation and investigating specific diagnoses is limited.

Purpose

To investigate the incidence rate, severity, burden, and mechanisms of foot and ankle injuries that (1) required visiting a medical team (medical attention foot and ankle injuries; MA-FAIs) and (2) prevented a dancer from fully participating in all dance-related activities for at least 24 hours after the injury (time-loss foot and ankle injuries; TL-FAIs) in 2 professional ballet companies.

Study Design

Descriptive epidemiological study.

Methods

Foot and ankle injury data across 3 seasons (2016-2017 to 2018-2019) were extracted from the medical databases of 2 professional ballet companies. Injury-incidence rate (per dancer-season), severity, and burden were calculated and reported with reference to the mechanism of injury.

Results

A total of 588 MA-FAIs and 255 TL-FAIs were observed across 455 dancer-seasons. The incidence rates of MA-FAIs and TL-FAIs were significantly higher in women (1.20 MA-FAIs and 0.55 TL-FAIs per dancer-season) than in men (0.83 MA-FAIs and 0.35 TL-FAIs per dancer-season) (MA-FAIs, P = .002; TL-FAIs, P = .008). The highest incidence rates for any specific injury pathology were ankle impingement syndrome and synovitis for MA-FAIs (women 0.27 and men 0.25 MA-FAIs per dancer-season) and ankle sprain for TL-FAIs (women 0.15 and men 0.08 TL-FAIs per dancer-season). Pointe work and jumping actions in women and jumping actions in men were the most common mechanisms of injury. The primary mechanism of injury of ankle sprains was jumping activities, but the primary mechanisms of ankle synovitis and impingement in women were related to dancing en pointe.

Conclusion

The results of this study highlight the importance of further investigation of injury prevention strategies targeting pointe work and jumping actions in ballet dancers. Further research for injury prevention and rehabilitation strategies targeting posterior ankle impingement syndromes and ankle sprains are warranted.

The Effect of Foot Position and Lean Mass on Jumping and Landing Mechanics in Collegiate Dancers

The purpose of this study was to investigate the effects of foot positioning and lean mass on jumping and landing mechanics in collegiate dancers. Thirteen dancers performed 3 unilateral and bilateral vertical jumps with feet in neutral and turnout positions. Dual-energy x-ray absorptiometry scans, jump height, vertical stiffness, and joint stiffness were assessed for relationships between foot positions. Jump heights were greater in right compared with left limb (P = .029) and neutral compared with turnout (P = .020) during unilateral jumping. In unilateral landing, knee stiffness was greater in turnout compared with neutral (P = .004) during the loading phase. Jump height (P < .001) was significantly increased, and vertical stiffness (P = .003) was significantly decreased during bilateral jumping in neutral compared with turnout. Significantly increased hip stiffness during the attenuation phase was observed in neutral compared with turnout (P = .006). Left-limb lean mass was significantly less than the right limb (P < .05). Adjustments for bilateral jumping were focused on hip stiffness, whereas there was a slight shift to knee strategy for unilateral jump.

Management of Stress Fractures in Ballet

Stress fractures are highly prevalent in ballet dancers and lead to notable time loss from dancing. Nutritional status, body composition, bone mineral density, and rate of increase in activity are among the components that influence risk for stress fractures. Proper evaluation and management of stress fractures is essential including a review of the causative factors involved in each stress injury. The purpose of this article was to summarize current evidence for risk factors involved in dancers' stress fractures to optimize prevention and treatment. Identified associated factors include low energy availability, low bone mineral density, low fat body composition, abnormal lower extremity biomechanics, genetic factors, and high training loads.

Evaluation of the Correlation Between Flamenco Dance and Ankle and Foot Posture

BACKGROUND

The practice of flamenco dance involves great biomechanical demands, comparable with a high-performance sport. The technical movements of the footwork tap, the jumps, and the turns increase the prevalence of injuries and pathologic disorders of the foot and lower limb. Limited research has examined adaptation of the foot posture and dorsiflexion of the ankle in flamenco dancing. Therefore, the aim of this study was to evaluate whether the practice of flamenco dancing produces modifications in the ankle's dorsiflexion range of motion, Foot Posture Index, or pronation.

METHODS

A cross-sectional observational study with intentional sampling was performed with 26 individuals (52 feet) in two groups: professional female flamenco dancers (n = 13) and nondancers (n = 13). The participants were assessed in a single session for ankle dorsiflexion, foot pronation (navicular drop test), and foot posture (Foot Posture Index).

RESULTS

Significant differences were found between the two groups for left foot Foot Posture Index (P = .007) and right foot navicular drop test (P = .006).

CONCLUSIONS

The results of this study indicate that flamenco dancing can produce modifications in the Foot Posture Index and foot pronation versus nondancers. Further research is required.

Type of Turnout and Injury Rates in Elite Dancers: A Critically Appraised Topic

Clinical Scenario: Dancers commonly stand in hip external rotation due to the esthetics that ballet requires. Increased external rotation is desired which leads dancers to find ways to compensate to increase their external rotation, an action known as compensated turnout. Dancers commonly rotate at the tibiofemoral joint and/or the talocrural joint to increase external rotation of the entire lower body, placing increased stress on these joints. This critically appraised topic focuses on the relationship between types of turn out and lower-extremity injury in dancers. Clinical Question: In elite dancers, does compensated, anatomical, or functional turnout influence lower-extremity injuries? Summary of Key Findings: Three studies met the inclusion criteria and were included in the analysis. One study demonstrated a relationship between compensated turnout and traumatic injuries, low back pain, and number of injuries in modern dancers. Greater compensated turnout in dancers was associated with a greater number of injuries. Two studies showed no relationship between anatomical or functional turnout and injuries in dancers. Clinical Bottom Line: Based on 3 level 2b studies, there is level C evidence to suggest that increased compensated turnout is associated with increased traumatic lower-extremity injuries, low back pain, and number of injuries in university modern dancers compared with dancers with a reduced angle of compensated turnout. This relationship was not found between anatomical or functional turnout and lower-extremity injuries in elite dancers. Strength of Recommendation: There is weak evidence to suggest that compensated turnout, but not anatomical or functional turnout, is related to lower-extremity musculoskeletal injury. More research is needed to study compensatory mechanisms in a broader range of dancers and the relationship to lower-extremity injury.

Sagittal Integral Morphotype of Female Classical Ballet Dancers and Predictors of Sciatica and Low Back Pain

The aims of this study were to describe the sagittal integral morphotype (SIM) of classical ballet (CB) dancers, and to establish predictor factors and their cut off values for high risk of experiencing sciatica or low back pain (LBP). This retrospective cohort study was performed in 33 female professional CB dancers. Data related to anthropometric parameters, CB dance experience, sciatica or LBP history, and sagittal spine curvatures were collected. A binary logistic regression and receiver-operating characteristic analysis were performed. The main spine misalignments observed in the SIM of CB dancers were thoracic functional hyperkyphosis, hypomobile kyphosis, and hypokyphosis, and those for the lumbar curvature were hyperlordotic attitude and functional hyperkyphosis. The lumbar curvature in slump sitting and trunk forward bending positions, together with the stature, were significant predictor factors of sciatica history, while the years of dance experience was a significant predictor factor of LBP history. The cut off values analysis revealed that dancers with a stature of 161 cm or less, and those with 14 years of experience or more, have a greater probability of experiencing sciatica or LBP history, respectively.

The Case for Retiring Flexibility as a Major Component of Physical Fitness

Flexibility refers to the intrinsic properties of body tissues that determine maximal joint range of motion without causing injury. For many years, flexibility has been classified by the American College of Sports Medicine as a major component of physical fitness. The notion flexibility is important for fitness has also led to the idea static stretching should be prescribed to improve flexibility. The current paper proposes flexibility be retired as a major component of physical fitness, and consequently, stretching be de-emphasized as a standard component of exercise prescriptions for most populations. First, I show flexibility has little predictive or concurrent validity with health and performance outcomes (e.g., mortality, falls, occupational performance) in apparently healthy individuals, particularly when viewed in light of the other major components of fitness (i.e., body composition, cardiovascular endurance, muscle endurance, muscle strength). Second, I explain that if flexibility requires improvement, this does not necessitate a prescription of stretching in most populations. Flexibility can be maintained or improved by exercise modalities that cause more robust health benefits than stretching (e.g., resistance training). Retirement of flexibility as a major component of physical fitness will simplify fitness batteries; save time and resources dedicated to flexibility instruction, measurement, and evaluation; and prevent erroneous conclusions about fitness status when interpreting flexibility scores. De-emphasis of stretching in exercise prescriptions will ensure stretching does not negatively impact other exercise and does not take away from time that could be allocated to training activities that have more robust health and performance benefits.

Relationship of Patellofemoral Angles and Tibiofemoral Rotational Angles With Jumper's Knee in Professional Dancers: An MRI Analysis

Background:

Jumper’s knee is a type of tendinopathy affecting the distal insertion of the quadriceps tendon (25% of cases) or the patellar tendon. It has been shown that frontal-plane measurements, such as genu valgum, genu varum, an increased quadriceps angle, a protuberant tibial tuberosity, patella alta, and short hamstring muscles, may be related to jumper’s knee.

Purpose:

To investigate the effects of tibiofemoral rotational angles and patellofemoral (PF) angles on the development of jumper’s knee in professional folk dancers.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

We examined 26 dancers (16 male, 10 female) with knee pain using magnetic resonance imaging (MRI), for a total of 32 knees. Of the knees, 21 with quadriceps tendinopathy (QT) and 7 with patellar tendinopathy (PT) were detected. Using MRI scans, we measured PF angles (PF sulcus angle, lateral PF angle, patellar tilt angle, lateral trochlear inclination angle, lateral patellar tilt angle, and PF congruence angle) and tibiofemoral rotational angles (condylar twist angle, posterior condylar angle, femoral Insall angle, tibial Insall angle, posterior tibiofemoral angle, and angle between the Whiteside line and posterior femoral condylar line) and noted specifics such as patella alta, patella baja, and the Wiberg classification of the patellar shape between the patients with versus without QT and between patients with versus without PT to understand if there was any relationship with tendinopathy.

Results:

No statistically significant difference was observed in age, sex, patella alta, or the Wiberg classification between the QT groups (with vs without) and between the PT groups (with vs without) (P > .05). Having QT was found to be significantly associated with the PF sulcus angle (P = .009), and having PT was found to be significantly associated with the femoral Insall angle (P = .029).

Conclusion:

Jumper’s knee was found to be associated with anatomic variations of the PF sulcus angle and rotation of the patellar tendon in relation to the femur (femoral Insall angle) on axial MRI scans in professional dancers. Unlike those of other athletes, dancers’ knees are exposed more to external rotation forces because of turnout, and this can be the cause of jumper’s knee.

Risk Factors for Lower-Extremity Injuries in Female Ballet Dancers: A Systematic Review

BACKGROUND

Ballet dancers have a high prevalence of injuries to the lower extremity. Many studies have investigated the relationship between dance injury and risk factors. However, risk factors for lower-extremity injury comparing recreational- and elite-level ballet dancers are scarce.

OBJECTIVE

To systematically review available original studies to assess risk factors for lower-extremity injury in female ballet dancers between recreational and elite ballet dancers.

DATA SOURCES

Five online databases [Web of Science, PubMed, OVID (Medline), EBSCO, and ProQuest] were searched systematically.

STUDY SELECTION

Included studies had an analytic study design published in the past 11 years and investigated an association between potential risk factors and lower-extremity injury in female ballet dancers.

STUDY APPRAISAL

Assessed independently by 2 reviewers using the Downs and Black (DB) criteria and Oxford Centre of Evidence-Based Medicine.

RESULTS

Seventeen studies were included. Alignment was a risk factor for lower-extremity injury in both recreational and elite ballet dancers. In elite ballet dancers, poor lumbopelvic movement control, inappropriate transversus abdominis contraction, decreased lower-extremity strength, and poor aerobic fitness were risk factors for lower-extremity injury. In recreational ballet dancers, hypermobility of the hip and ankle and longer training hours were risk factors for lower-extremity injury. Mean DB score was 15.94 (SD 1.57). The majority of studies were retrospective cohort studies or had poor follow-up, with 7 level 2b studies, 6 level 3b studies (cross-sectional), and 4 level 1b studies (prospective cohort with good follow-up).

CONCLUSIONS

Alignment was identified as a common risk factor for recreational and elite ballet dancers. Other risk factors differed between recreational ballet dancers and elite ballet dancers. Future studies are warranted to use a prospective study design, identify dance level-specific risk factors, and implement evidence-based prevention strategies.

The effects of acute physical fatigue on sauté jump biomechanics in dancers

Dancers spend large amounts of time practicing and performing, where fatigue may occur, resulting in adverse movement patterns. The purpose of this study was to compare sauté landings before and after acute physical fatigue in experienced female dancers. Twenty-one dancers completed 10 sauté jumps before and after a dance-specific fatigue protocol. A 12-camera motion capture system and a force plate were utilized to collect three-dimensional kinematic and kinetic data. After fatigue, dancers demonstrated an increase in mediolateral centre of mass displacement, pelvis excursion, peak knee abduction, peak ankle eversion and external rotation, as well as decreased peak metatarsophalangeal (MTP) joint extension, indicating less desirable movement patterns. Peak vertical ground reaction force was decreased after fatigue due to a softer landing strategy, demonstrated by increased peak hip flexion, knee flexion, and ankle dorsiflexion. There was some indication of shifting demands demonstrated by an increased peak knee extensor moment and decreased peak MTP flexor moment after fatigue. With jump landing kinematics and kinetics affected after only an average of 5 minutes of dancing, dancers may benefit from developing greater endurance and more eccentric strength to allow them to slow down properly while landing and to sustain the aesthetic demands throughout performance.

Does forced or compensated turnout lead to musculoskeletal injuries in dancers? A systematic review on the complexity of causes

Injury prevalence in dancers is high, and misaligned turnout (TO) is claimed to bear injury risk. This systematic review aimed to investigate if compensating or forcing TO leads to musculoskeletal injuries. A systematic literature review was conducted according to the PRISMA Guidelines using the databases of PubMed, Embase, Emcare, Web of Science, Cochrane Library, Academic Search Premier, and ScienceDirect. Studies investigating the relationship between compensated or forced TO and injuries in all genders, all ages, and levels of dancers were included. Details on misaligned TO measurements and injuries had to be provided. Screening was performed by two researchers, data extraction and methodological quality assessment executed by one researcher and checked by another. 7 studies with 1293 dancers were included. Methodological quality was low due to study designs and a general lack of standardised definition of pathology and methods of assessment of misaligned TO. The studies investigating the lower extremities showed a hip-focus only. Non-hip contributors as well as their natural anatomical variations were not accounted for, limiting the understanding of injury mechanisms underlying misaligned TO. As such no definite conclusions on the effect of compensating or forcing TO on musculoskeletal injuries could be made. Total TO is dependent on complex motion cycles rather than generalised (hip) joint dominance only. Objective dual assessment of maximum passive joint range of motion through 3D kinematic analysis in combination with physical examination is needed to account for anatomical variations, locate sites prone to (overuse)injury, and investigate underlying injury mechanisms.

LOW BACK PAIN AND INJURY IN BALLET, MODERN, AND HIP-HOP DANCERS: A SYSTEMATIC REVIEW

Background

Low back pain is believed to be a common complaint among dancers; however, a comparison across recent research is needed to support or disprove this assertion across genres.

Purpose

To determine the prevalence of low back pain and low back injury in ballet, modern, and hip-hop dancers through a systematic literature review. A secondary goal was to identify trends amongst dance genres, level of mastery, gender, and age, if possible.

Study Design

Systematic Review of the Literature.

Methods

PRISMA search strategy of terms relating to dance and low back pain was conducted within the Pubmed, MEDLINE, SPORTDiscus, Web of Science, and the archives of the Journal of Dance Medicine and Science databases between November 2017 and March 2018. Inclusion criteria were published articles that addressed low back pain or injury in ballet, modern, or hip-hop dance population. Exclusion criteria included studies relating to specific pathologies or studies that did not report specific dance genre. All included articles were assessed for quality using a modified grading evaluation and a Modified Newcastle-Ottawa Risk of Bias assessment.

Results

Twenty-five ballet articles, five modern, and three hip-hop articles met the inclusion criteria, for a total of 33 articles. Twenty-five of the 33 studies relied on a questionnaire to gather data. Risk of bias results ranged from 3-7/10 and quality of studies ranged from Good I to Limited III. Prevalence of low back pain seems relatively high in ballet dance (range: 20.3%-79% of total dancers are affected). Little research exists on the prevalence of back pain in modern or hip-hop dancers, but hip-hop dancers also seem likely to have low back pain (range: 46.6%-85.7% of total dancers are affected). Low back injuries are also present in ballet (range: 2.1%-88% of total injuries), modern (range: 8.6%-21.6% of total injuries), and hip-hop (range: 26.3%-69.6%).

Conclusion

Ballet dancers seem to be at risk for low back pain or injury independent of gender, age or level of mastery; however, there is not enough evidence to draw any conclusions about modern dancers or hip-hop dancers and their risk for low back pain/injury currently. Future higher-level studies are needed with reduced risk of bias.

Level of Evidence

2a.

External and Total Hip Rotation Ranges of Motion Predispose to Low Back Pain in Elite Spanish Inline Hockey Players

Low back pain (LBP) is a common ailment in competitive athletes. Although the association between limited range of motion (ROM) and prevalence of LBP has been widely investigated in other sports, there is no research about this topic in inline hockey (IH). The main purposes of this study in IH players were (1) to analyze the association between hip ROM and LBP and (2) to establish a diagnostic cutoff for ROM of high risk of LBP. Twenty elite IH players from the two Spanish National Teams (male and female) were assessed for passive maximum hip ROMs; the movement evaluated were the hip external [HER] and internal [HIR] rotation, hip flexion with flexed [HF-KF] and extended [HF-KE] knee, hip adduction with flexed hip [HAD-HF], hip abduction with neutral [HAB] and flexed [HAB-HF] hip, and hip extension [HE]. LBP was retrospectively monitored for the last 12 months before the date of ROM assessment by using a questionnaire. The data were analyzed via a binary logistic regression and receiver operating characteristic curves. The 70% of players had developed LBP during the retrospective study period. Significant differences between LBP group and asymptomatic group for HER (p = 0.013, d [Cohen’s effect size] = 1.17) and hip total rotation [HTR] (p = 0.032, d [Cohen’s effect size] = 1.05) were observed. The cutoff points with the greatest discriminatory capacity were 56.5° for HER and 93° for HTR ROMs.

Correlation between degree of hallux valgus and kinematics in classical ballet: A pilot study

Hallux valgus is a serious medical concern for classical ballet dancers. Although it is well-known that progression of hallux valgus is related to inappropriate movement techniques in classical ballet, the kinematic relationship between the degree of hallux valgus and ballet techniques has not been substantiated. To develop proper training methods that prevent progression of hallux valgus, this study aimed to investigate the relationship between the degree of hallux valgus and movement techniques in classical ballet. Seventeen female classical ballet dancers at the advanced college-level participated in this study. Kinematic analysis of standing and plié in the first position was conducted via video capture technique. The Pearson product-moment correlation analysis was performed to examine the degree of hallux valgus and the following three kinematic variables: (1) the extent to which turnout is forced by other joints in the lower extremity than the hip joint, (2) the direction difference between the knee and toe in the transverse plane, and (3) the pelvis obliquity angle. Among these kinematic variables, we found a significant correlation between the hallux valgus angle and the pelvis obliquity angle during plié (P = .045). The greater the hallux valgus angle, the greater the retroversion of the pelvis, a result which was contrary to our prediction. We present the first evidence that the degree of hallux valgus correlates with kinematics in a very basic technique of classical ballet.

On the track of the ideal turnout: Electromyographic and kinematic analysis of the five classical ballet positions

The turnout of the lower extremities is the major component of the classical ballet positions (CPs) and correctly is initiated in the hips. The aim of this research was to determine the differences in the electromyographic and kinematic variables in the five CPs in ballet students with greater and lesser amount of passive hip external rotation (HER). A group of 14 female pre-professional ballet dancers 11–16 years of age participated in the study. Based on the amount of passive HER, participants with higher values made up greater rotation group (n = 7) whereas those with lesser values formed lesser rotation group (n = 7). Electromyographic activity of 14 muscles from right side of the trunk and right lower extremity was recorded with the surface electrodes while subjects were standing in all five CPs (CP1-CP5). The external rotation of the hips, knees and feet were recorded with the motion capture system. The kinematic differences between the groups were revealed in asymmetric positions CP4 and CP5 where foot progression angle was significantly lesser in forward than backward setting only in lesser rotation group. In lesser rotation group the ankle and back muscles were more engaged in CPs while abdominal and hip muscles less when compared with greater rotation group. This finding suggests that in the group with lesser passive HER the mechanism of forced turnout was employed. The most remarkable finding in our work was that various electromyographic patterns can be observed between groups in all CPs, while kinematic differences may be marked only in asymmetric positions.

Prevalence and unique patterns of lower limb hypermobility in elite ballet dancers

OBJECTIVES

Determine the prevalence of lower limb hypermobility in elite dancers and secondarily to describe the patterns of mobility.

DESIGN

Cross sectional.

SETTING

Self-report questionnaires and physical assessments were undertaken at a tertiary dance institution and a professional ballet company.

PARTICIPANTS

Fifty-seven pre-professional and 29 professional ballet dancers (21±4years, 64% female, mean 13.7years training) were recruited.

MAIN OUTCOME MEASURES

Lower Limb Assessment Score (LLAS) was used to assess hypermobility. Prevalence was determined by descriptive statistics, between-leg and -group comparisons were analysed using the chi-square statistic and the pattern of mobility by cluster analyses.

RESULTS

The right leg was significantly more hypermobile than the left for the whole cohort (44% vs 40% meeting ≥7/12 for the LLAS; LLAS mean/12(SD): right:5.0(2.4) and 7.6(1.9); left:4.8(2.1) and 6.7(2.0) in pre-professionals and professionals respectively (p = 0.02)). Subtalar pronation (p < 0.001) and hip abduction/external rotation (left:p = 0.01; right:p < 0.001) were significantly more hypermobile bilaterally in professionals. Three hypermobility profiles on the left and four on the right lower limb were identified.

CONCLUSIONS

This paper presents unique lower limb hypermobility profiles identified in elite dancers.

Patellofemoral pain, body morphology and alignment in female pubertal dancers: One-year follow-up

The aim of this study was to assess changes in body morphology, anatomical alignment and prevalence of patellofemoral pain (PFP) in young female dancers along one year of pubertal growth, and to identify the risk factors related to PFP in these young dancers. Both legs of 60 dancers were evaluated during grade 7 and again after 1-year. At each of these points in time, the dancers were interviewed concerning their background, and anthropometric measurements, lower-limb physical examinations and knee ultrasound scans were performed. Morphological parameters changed significantly from baseline to follow-up. PFP was found in 53.3% of the dancers' knees at baseline. At follow-up, 55.4% of the asymptomatic knees at baseline developed PFP, and only 9.4% of the symptomatic knees at baseline recovered. Lower BMI was identified among dancers who developed PFP during follow-up compared with dancers with no PFP, either at baseline or at follow-up. A positive grinding and positive Patellar Inhibition Test (PIT) were found to be risk factors for PFP at follow-up. A high prevalence of young dancers suffered PFP, from injuries they sustained mostly during the 1-year of dance practice. Parameters predisposing the dancers to PFP should be identified at early stages of dance class.

An analysis of the foot in turnout using a dance specific 3D multi-segment foot model

Introduction

Recent three-dimensional (3D) kinematic research has revealed foot abduction is the strongest predictor of standing functional and forced turnout postures. However, it is still unknown how the internal foot joints enable a large degree of foot abduction in turnout. The primary purpose of this study was to use a dance specific multi-segment foot model to determine the lower leg and foot contributions to turnout that female university-level ballets use to accentuate their turnout.

Methods

Eighteen female dance students (mean age, 18.8 ± 1.6 years) volunteered for this study. Retro-reflective markers were attached to the dancers’ dominant foot. Each dancer performed three repetitions of functional turnout, forced turnout and ten consecutive sautés in first position. Repeated measures ANOVA with Bonferroni adjustments for the multiple comparisons were used to determine the kinematic adjustments, hindfoot eversion, midfoot and forefoot abduction, navicular drop (i.e. lowering of the medial longitudinal arch) and first metatarsophalangeal joint abduction between natural double leg up-right posture and the first position conditions.

Results

Hindfoot eversion (4.6°, p < 0.001) and midfoot abduction (2.8°, p < 0.001) significantly increased in functional turnout compared to the natural double leg up-right posture. Thirteen dancers demonstrated increased first metatarsophalangeal joint (MTPJ) abduction in forced turnout, however no statistically significant increase was found. Navicular drop during sautés in first position significantly increased by 11 mm (p < 0.001) compared to the natural double leg up-right posture.

Conclusion

Our findings suggest dancers do pronate, via hindfoot eversion and midfoot abduction in both functional and forced turnout, however, no immediate association was found between forced turnout and first MTPJ abduction. Foot pronation does play a role in achieving turnout. Further prospective research on in situ measures of the lower limb in turnout and injury surveillance is required to improve our understanding of the normal and abnormal dance biomechanics.

Electronic supplementary material

The online version of this article (10.1186/s13047-019-0318-1) contains supplementary material, which is available to authorized users.

Inter-rater and intra-rater reliability of a clinical protocol for measuring turnout in collegiate dancers

Reliable methods of measuring turnout in dancers and comparing active turnout (used in class) with functional (uncompensated) turnout are needed. Authors have suggested measurement techniques but there is no clinically useful, easily reproducible technique with established inter-rater and intra-rater reliability. We adapted a technique based on previous research, which is easily reproducible. We hypothesized excellent inter-rater and intra-rater reliability between experienced physical therapists (PTs) and a briefly trained faculty member from a university's department of dance. Thirty-two participants were recruited from the same dance department. Dancers' active and functional turnout was measured by each rater. We found that our technique for measuring active and functional turnout has excellent inter-rater and intra-rater reliability when performed by two experienced PTs and by one briefly trained university-level dance faculty member. For active turnout, inter-rater reliability was 0.78 among all raters and 0.82 among only the PT raters; intra-rater reliability was 0.82 among all raters and 0.85 among only the PT raters. For functional turnout, inter-rater reliability was 0.86 among all raters and 0.88 among only the PT raters; intra-rater reliability was 0.87 among all raters and 0.88 among only the PT raters. The measurement technique described provides a standardized protocol with excellent inter-rater and intra-rater reliability when performed by experienced PTs or by a briefly trained university-level dance faculty member.

Association between coping skills, past injury and hip pain and function in adolescent elite female ballet dancers

OBJECTIVES

The purpose of this study was to investigate the relationship between coping skills and current hip pain and function scores in ballet dancers. Secondly, we examined the relationship between coping skills and past injuries. Thirdly, we investigated the association between past injuries and current pain and function scores.

METHODS

This was a cross-sectional observational study. Twenty-six young elite female dancers (mean age 15.9 years, range 14-17 years) participated. Participants completed surveys indicating past injury history, rating pain and function on the short International Hip Outcome Tool (iHOT-12), and assessing coping skills on the Athletic Coping Skills Inventory Score (ACSI-28). Independent t-tests, Cohen's d, effect size, chi-square and correlation coefficient and determination analyses were conducted.

RESULTS

There was no significant relationship between iHOT-12 scores and ACSI-28 scores (r = -0.250, p = 0.087). There was no significant difference (p = 0.289) in past injuries comparing those with ACSI-28 scores above and below the mean ACSI-28. A significant moderate negative correlation was detected between both iHOT-12 scores and total past injuries (r = -0.609, p < 0.001), and iHOT-12 scores and past non-hip injuries (r = -0.628, p < 0.001).

CONCLUSION

Past injuries may influence current hip pain and function in young female dancers. Correlation determination (r²) indicated that 37% of current pain and function scores were explained by total past injuries in a small group of young high-level ballet dancers. Further research should engage a prospective design to investigate the predictive ability of findings.

Screening Tools as a Predictor of Injury in Dance: Systematic Literature Review and Meta-analysis

BACKGROUND

Dance involves movements of complexity and physical intensity which result in stress on the body. As a consequence, dancers are at risk of injury which can impact on their well-being. Screening tools are used for injury prevention to identify those dancers at risk of injury. The aim of this study was to investigate which screening tools can predict injury in dancers, encompassing all dance genres, levels and ages.

METHODS

An electronic search of seven databases from their inception to December 2017 was conducted. The databases were the Allied and Complementary Medicine Database (AMED), CINAHL, eBOOK Collection (EBSCOhost), MEDLINE, Cochrane Database of Systematic Reviews, SPORTDiscus and PEDro: the Physiotherapy Evidence Base. The following search terms were used: (i) Dance AND injury AND Screening, (ii) Screening AND dance and (iii) Musculoskeletal AND Screening AND Dance. Studies were assessed using a 20-point scoring tool, and eligible studies were included in a meta-analysis.

RESULTS

The mean methodological quality score was 12.2 points. Injured dancers had a significantly higher compensated turnout range of motion than non-injured dancers: pooled mean difference of compensated turnout (23.29°; 95% CI 14.85-31.73; P < 0.00001; I2 = 0%). Injured dancers had significantly greater functional turnout range of motion when compared to non-injured dancers: pooled mean difference of functional turnout (14.08°; 95% CI 7.09-21.07; P < 0.0001; I2 = 0%). There also some evidence for use of hip range of motion as a predictor of dance injury.

CONCLUSIONS

Some evidence exists for the potential use of dance-specific positions as a predictor of injury. A number of studies were limited by a lack of prospective injury design, injury definition and self-reporting of injury.

The association between menarche, intensity of training and passive joint ROM in young pre-professional female dancers: A longitudinal follow-up study

OBJECTIVES

To determine the association between the status of menarche (yes/no), the intensity of training and the potential to improve passive joint range of motion (ROM) over a 12-month period of dance training.

DESIGN

Prospective cohort study.

SETTING

Dance studio.

PARTICIPANTS

Fifty-nine female dancers aged 12.8 ± 0.5.

MAIN OUTCOME MEASURES

The dancers were asked about their dance intensity and screened for anthropometric parameters and passive joint ROM in Grades 7 and 8.

RESULTS

Along the 12 months of dance training, we found significantly increased ankle-foot en-pointe, hip abduction, and hip external rotation (ER); significantly decreased hip internal rotation (IR); and significant increased hip ER:IR ratio. In Grade 7, 26 dancers (44.1%) reached menarche (Yes menarche); in Grade 8 an additional 23 dancers (39.0%) reached menarche (No/Yes menarche); and 10 dancers (16.9%) had not reached menarche (No menarche). MANOVA (mixed models) with repeated measures to compare joint ROM between the three menarche groups (Yes; No/Yes; No), with h/week dance practice as a co-variant, showed that hip ER, ankle-foot en-pointe, and ER:IR were significantly correlated with h/week in all three menarche groups.

CONCLUSIONS

Most passive joint ROM can be improved over 12 months of dancing around the age onset of menarche. H/week of dance practice is a main factor contributing to improved hip ER, ankle-foot en-pointe and ER/IR ratio.

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

OBJECTIVES

To examine risk factors for injury in pre-professional modern dancers.

DESIGN

With prospectively designed screening and injury surveillance, we evaluated four risk factors as categorical predictors of injury: i) hypermobility; ii) dance technique motor-control; iii) muscle tightness; iv) previous injury. Screening and injury data of 180 students enrolled in a university modern dance program were reviewed over 4-yrs of training. Dancers were divided into 3-groups based on predictor scores. Dance exposure was based on hours of technique classes/wk. Negative binomial log-linear analyses were conducted with the four predictors, p < 0.05.

RESULTS

Dancers with low and high Beighton scores were 1.43 and 1.22 times more likely to sustain injury than dancers with mid-range scores (p ≤ 0.03). Dancers with better technique (low or medium scores) were 0.86 and 0.63 times less likely to sustain injury (p = 0.013 and p < 0.001) compared to those with poor technique. Dancers with one or 2-4 tight muscles were 2.7 and 4.0 times more likely to sustain injury (p ≤ 0.046). Dancers who sustained 2-4 injuries in the previous year were 1.38 times more likely to sustain subsequent injury (p < 0.001).

CONCLUSIONS

This contributes new information on the value of preseason screening. Dancers with these risk factors may benefit from prevention programs.

The Relationship Between Range of Motion and Injuries in Adolescent Dancers and Sportspersons: A Systematic Review

Background: The frequent and intensive training and performance of pre-professional ballet dancers and sportspersons is offered at a time when young ballet dancers and young athletes may be vulnerable to injury due to the progress through adolescence and growth spurts.

Hypothesis: There are changes in range of motion during the progress through adolescence and growth periods in dancers and sportspersons. These changes in ROM can be linked to the increase of injury.

Objectives: The primary aim of this systematic review is to determine whether there are changes in ROM during the progress through adolescence and growth spurts in dancers and sportspersons. The secondary aim is to determine whether these changes can predict the risk of injuries for adolescent dancers and sportspersons.

Search strategy: Pubmed, Cochrane Register of Controlled Trails (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), EBSCO Host databases: CINAHL Plus, MEDLINE, SPORTDiscus, Embase were searched using MeSH terms. Manual search in the Journal of Dance Medicine and Science and screening of the reference lists of identified studies and reviews was conducted.

Selection criteria: Studies included adolescent dancers and sportspersons, aged 8–18, both sexes, growth spurt related to changes in ROM and injury incidence.

Data collection and analysis: Search strategy was performed in the flow diagram of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Two reviewers independently appraised each included study using Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) for methodological quality of the included studies. For data extraction, the following information was systematically extracted: first author and year of publication, study design, participants (sample size of mean age), age, maturation (if assessed), intervention, outcome(s), and some notes of each study. For evaluation of the risk of bias and precision the Research Triangle Institute Item Bank (RTI-IB) is included.

Main results: Seven observational studies met the inclusion criteria of this current review. The results of this review suggest that there are changes in ROM during the progress through adolescence and growth spurts in dancers and sportspersons. These changes may lead to an increase in injury incidence.

Conclusion: There is evidence linking to changes in ROM during the progress through adolescence and growth spurts in dancers and sportspersons. These changes in ROM may be related to injury incidence.

Lower leg and foot contributions to turnout in female pre-professional dancers: A 3D kinematic analysis

Turnout is a central element of classical ballet which involves sustained external rotation of the lower limbs during dance movements. Lower leg and foot compensation mechanisms which are often used to increase turnout have been attributed to the high incidence of lower limb injury in dancers. Evaluation of dancers' leg posture is needed to provide insight into the lower limb kinematic strategies used to achieve turnout. The primary purpose of this study was to use 3D kinematic analyses to determine the lower leg and foot compensations that are incorporated by female university dancers to accentuate their turnout. Active and passive external tibiofemoral rotation (TFR) was also measured. A moderate-strong negative relationship was observed between hip external rotation (HER) and foot abduction in the three first position conditions. A moderate negative relationship was found between passive TFR and foot abduction in all first position conditions. Our findings suggest dancers are more likely to pronate, than rotate the knee to compensate for limited HER. Dancers with a limited capacity to pronate may force additional rotation via the knee. Ongoing research would benefit from more in-depth analyses of the foot/ankle complex using a multi-segment foot model.

Métodos usados para avaliar o en dehors ou turnout de dançarinos e bailarinos clássicos: revisão da literatura

RESUMO A técnica do ballet clássico exige a realização máxima do en dehors ou turnout, caracterizado pela rotação externa de membros inferiores. Considerando a sua importância, diversos protocolos para a sua avaliação e mensuração têm sido propostos. O objetivo desta revisão foi investigar sistematicamente quais os métodos utilizados para avaliar o turnout de bailarinos clássicos e/ou praticantes de ballet clássico existentes atualmente. A busca foi feita nas bases de dados Scopus, Science Direct e PubMed, no mês de fevereiro de 2016, e os artigos encontrados deveriam: estar redigidos na língua inglesa, avaliar bailarinos clássicos ou dançarinos que praticassem ballet clássico e mensurar o en dehors ou turnout. Foram encontrados 593 artigos, dos quais 25 foram pré-selecionados para esta revisão, apresentando quinze diferentes métodos e instrumentos de mensuração do turnout: cinemetria; inclinômetro; turnout protactor ou transferidor para medir o turnout; goniômetro; Dupuis Tropometer; transferidor original; fotos dos sujeitos; discos rotacionais; teste de flexibilidade de Nicholas; flexímetro; desenho clínico dos pés; sujeito sobre um pedaço de papel ou solo ou quadro branco; ressonância magnética; filmagem do sujeito executando sequência de passos; Dasco Pro Angle Finder. Esta revisão apresenta forte evidência para afirmar que não há, até o presente momento, um método ou instrumento padrão-ouro para mensuração do turnout de bailarinos, de modo que esta costuma ser adaptada e escolhida de acordo com o objetivo de cada estudo.

Hip and Groin Injuries in Dancers: A Systematic Review

CONTEXT

Injury data on hip and groin injuries vary, and these injuries are often misrepresented or overlooked for more commonly seen injuries, such as those to the foot and ankle.

OBJECTIVE

To provide a systematic review of the injury rates of hip and groin pathology in dancers and look to establish a better understanding of the occurrence of hip and groin injuries in the dancer population.

DATA SOURCES

A literature search was performed using PubMed and CINAHL databases for articles published between 2000 and 2016.

STUDY SELECTION

Inclusion criteria consisted of (1) documentation of the number of hip and/or groin injuries, (2) study population consisting of dancers whose training included some level of ballet, and (3) studies of levels 1 through 3 evidence.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 3.

DATA EXTRACTION

A single reviewer identified studies that met the inclusion criteria. The number of overall injuries, hip/groin injuries, study participants, injured participants, training hours per week, mean age of study group, injury definition, injury reporting method, and study time frame were extracted.

RESULTS

Thirteen unique studies were included in the descriptive analysis. Of the 2001 dancers included in this study, 3527 musculoskeletal injuries were seen in 1553 dancers. Of these, 345 injuries were localized to the hip and groin region (overall rate, 17.2%). An incidence rate of 0.09 hip and groin injuries per 1000 dance-hours was seen in the selected cohort studies. Of 462 professional dancers, 128 hip/groin injuries were recorded, for an injury rate of 27.7%. Of the 1539 student dancers, 217 hip/groin injuries were recorded, for an injury rate of 14.1% ( P < 0.01).

CONCLUSION

Data on hip and groin injuries have many limitations. However, these injuries represent an important health issue for dancers of all skill levels, encompassing 17.2% of musculoskeletal injuries seen in dancers. An increasing rate of hip/groin injuries is seen in professional dancers compared with students.

Lower-Leg and Foot Contributions to Turnout in University-Level Female Ballet DancersA Preliminary Investigation

BACKGROUND

Turnout in ballet is produced through summation of the joint structure characteristics and ranges of motion at the hip, knee, ankle, and foot. Contributions of the hip joint to functional turnout in dancers have received extensive examination, whereas little is known about contributions from the knee, ankle, and foot. The aim of this study was to explore the nonhip components of turnout to dancers' functional turnout in first position by assessing passive external tibiofemoral rotation and active measures of foot pronation, ie, navicular drop and Foot Posture Index.

METHODS

Nineteen female university-level dance students aged 16 to 19 years participated in this descriptive correlational study. External tibiofemoral rotation, navicular drop, Foot Posture Index, and functional turnout were measured for the participants' right and left legs.

RESULTS

Regression analyses revealed a weak relationship between passive external tibiofemoral rotation and functional turnout. Correlation analysis revealed a moderate negative relationship between passive tibiofemoral external rotation and the Foot Posture Index in functional turnout.

CONCLUSIONS

These findings suggest that the lower leg does contribute to dancers' overall position of functional turnout. However, current methods are not useful in predicting a dancer's lower-leg contribution and alignment in functional turnout in first position.

Single-leg squats can predict leg alignment in dancers performing ballet movements in "turnout"

The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve “turning out” or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in “turned out” postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat.

Postural adjustments in young ballet dancers compared to age matched controls

OBJECTIVES

The purpose of the study was to use photogrammetry to evaluate the posture of ballet practitioners compared to an age-matched control group.

DESIGN

One hundred and eleven 7- to 24-year-old female volunteers were evaluated and were divided into two groups: the ballet practising group (n = 52) and the control group (n = 59), divided into three subgroups according to age and years of ballet experience.

RESULTS

Dancers with 1-3 years experience compared to controls of the same age shows alterations in External Rotation Angle (P < 0.05). Dancers 4-9 years experience show alterations in Lumbar Lordosis, Pelvis Tilt Angle and Navicular Angle Right and Left (P < 0.05). Dancers with over 9 years experience show alterations in External Rotation and Navicular Angle Left (P < 0.05).

CONCLUSIONS

Research shows there are differences between dancers and controls. In the groups 1-3 years and over 9 years of experience, the External Rotation Angle is greater. In the group 4-9 years of experience the Lumbar Lordosis Angle is greater and Pelvis Tilt, Navicular Angle Left and Right are smaller. In more than 9 years of ballet experience, the Navicular Angle Left is smaller.

Incidence and Prevalence of Musculoskeletal Injury in Ballet: A Systematic Review

BACKGROUND

Most published studies on injuries in the ballet dancer focus on the lower extremity. The rigors of this activity require special training and care. By understanding prevalence and injury pattern to the musculoskeletal system, targeted prevention and treatment for this population can be developed.

PURPOSE

To determine the incidence and prevalence of musculoskeletal injuries in ballet.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review registered with PROSPERO was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Level 1 through 4 evidence studies reporting incidence of musculoskeletal injuries in male and female ballet dancers were included, with the numbers and types of injuries extracted from each. Injury rates were recorded and calculated based on professional status, sex, and nature of injury. Incidence was defined as number of injuries sustained over a specific time. Prevalence was defined as proportion of subjects with an injury at a given point in time.

RESULTS

The studies analyzed reported injury incidence or prevalence in more than 1365 amateur and 900 professional dancers. The mean age was 16.2 years among amateur and 27.0 years among professional dancers. The incidence of injury among amateur dancers was 0.99 and 1.09 injuries per 1000 dance hours in males and females, respectively; 75% of injuries were overuse, with similar rates among males and females. In professional dancers, the incidence of injury was 1.06 and 1.46 injuries per 1000 dance hours in males and females, respectively, and 64% of female injuries were overuse, compared with 50% in males (P < .001). Only 3 studies provided prevalence data, including 62% prevalence of lumbosacral pain, 58% painful snapping hip, and 29% patellofemoral pain. Lower extremity injuries comprised 66% to 91% of all injuries, with the foot and ankle accounting for 14% to 57%.

CONCLUSION

The overall incidence of injury among amateur and professional ballet dancers is 0.97 and 1.24 injuries per 1000 dance hours, respectively. The majority are overuse in both amateur and professional dancers, with amateur ballet dancers showing a higher proportion of overuse injuries than professionals (P < .001). Male professional dancers show a higher proportion of traumatic injuries, accounting for half of their injuries (P < .001).

Effect of Mulligan's and Kinesio knee taping on adolescent ballet dancers knee and hip biomechanics during landing

Taping is often used to manage the high rate of knee injuries in ballet dancers; however, little is known about the effect of taping on lower-limb biomechanics during ballet landings in the turnout position. This study investigated the effects of Kinesiotape (KT), Mulligan's tape (MT) and no tape (NT) on knee and hip kinetics during landing in three turnout positions. The effect of taping on the esthetic execution of ballet jumps was also assessed. Eighteen pain-free 12-15-year-old female ballet dancers performed ballet jumps in three turnout positions, under the three knee taping conditions. A Vicon Motion Analysis system (Vicon Oxford, Oxford, UK) and Advanced Mechanical Technology, Inc. (Watertown, Massa chusetts, USA) force plate collected lower-limb mechanics. The results demonstrated that MT significantly reduced peak posterior knee shear forces (P = 0.025) and peak posterior (P = 0.005), medial (P = 0.022) and lateral (P = 0.014) hip shear forces compared with NT when landing in first position. KT had no effect on knee or hip forces. No significant differences existed between taping conditions in all landing positions for the esthetic measures. MT was able to reduce knee and the hip forces without affecting the esthetic performance of ballet jumps, which may have implications for preventing and managing knee injuries in ballet dancers.

Injuries in female dancers aged 8 to 16 years

CONTEXT

Most studies of injured dancers have been carried out on professional adult dancers; data on young, nonprofessional injured dancers are sparse.

OBJECTIVE

To identify the types of injuries sustained by recreational dancers and to examine their association with age, joint range of motion, body structure, age at menarche, presence of anatomic anomalies, and physical burden (i.e., practice hours en pointe).

DESIGN

Descriptive epidemiology study.

SETTING

The Israel Performing Arts Medicine Center, Tel Aviv.

PATIENTS OR OTHER PARTICIPANTS

A total of 569 injured female dancers, aged 8 to 16 years.

MAIN OUTCOME MEASURE(S)

Dependent variables were 61 types of current injuries that were later classified into 4 major categories: knee injuries, foot and ankle tendinopathy, back injuries, and other injuries. Independent variables were age, joint range of motion, body size and shape, age at menarche, anatomic anomalies, and dance discipline (e.g., hours of practice per week en pointe).

RESULTS

At least 1 previous injury had been sustained by 42.4% of the dancers. The most common injuries involved the knee (40.4%), followed by other injuries (23.4%). The relative frequency of back injuries and tendinopathy decreased with age, whereas knee injuries increased. Types of injuries were significantly associated with ankle plantar flexion, hip external rotation, hip abduction, and knee flexion. Multinomial regression analysis revealed only 3 predictive variables (with other as baseline), all for back injury: scoliosis, age, and hip external rotation.

CONCLUSIONS

Joint range of motion and scoliosis may signal the potential for future injury. Young dancers (less than 10 years of age) should not be exposed to overload (especially of the back) or extensive stretching exercises.

Influence of turnout on foot posture and its relationship to overuse musculoskeletal injury in professional contemporary dancers: a preliminary investigation

BACKGROUND

The angle of turnout is thought to predispose professional dancers to overuse musculoskeletal injuries of the lower limb; yet, the influence of angle of turnout on foot posture is currently unknown.

METHODS

Twelve professional contemporary dancers (five women and seven men; mean age, 26.8 years) were recruited. The angle of gait and angle of turnout were measured using a quasi-static clinical tracing method. Foot posture was assessed in the base of gait and angle of turnout using the Foot Posture Index. Each dancer completed a dance history and injury questionnaire.

RESULTS

The results show a tendency toward a pronated foot posture (mean, 9°) in the angle of turnout position. A significant relationship was noted between the Foot Posture Index and angle of turnout (ρ = 0.933-0.968, P < .01) and between the number of reported injuries and change in foot posture in the angle of turnout (ρ = 0.789, P < .01) (right foot only). Twenty-eight injuries were reported; male dancers experienced a mean of 2.8 injuries and females a mean of 1.6 injuries. An inverse relationship was noted between age at training initiation and total reported injuries (r =-0.867, P < .01). All of the dancers reported a history of injury to the spine or lower limb, and 9 of the 12 reported an injury within the previous 12 months.

CONCLUSIONS

Turnout is one of the most fundamental aspects of dance technique. This study suggests a trend toward pronation in angle of turnout and a link to lower-limb musculoskeletal injury.

Management of dancers with symptomatic accessory navicular: 2 case reports

STUDY DESIGN

Case report.

BACKGROUND

Symptomatic accessory navicular can be a source of pain and disability. The treatment considerations for accessory navicular in dancers may differ due to increased demands on the foot, the repetitive nature of the movements, and the specific footwear required. The purpose of this report is to describe the management (1 conservative and 1 postoperative) of 2 adolescent dancers with symptomatic accessory navicular.

CASE DESCRIPTIONS

Case 1 was an 11-year-old female who underwent surgical excision of a symptomatic accessory navicular. Case 2 was a 15-year-old female who, following a traumatic injury that caused pain judged to be related to her accessory navicular, was managed nonsurgically. Treatment included pain management, range-of-motion exercises, trunk and lower extremity strengthening, balance and proprioception training, orthoses, crosstraining, and a guided return-to-dance progression.

OUTCOMES

Both patients had improved pain, dance technique, strength, and patient-reported outcome scores that allowed a full return to dance.

DISCUSSION

The 2 dancers presented here had foot pain believed to be related to a symptomatic accessory navicular. In both cases, treatment targeted specific impairments to improve function and disability. The guided progression of activities was intended to facilitate a return to dance that protected healing tissues and prevented a recurrence of symptoms. Clinicians should be aware of the effect of a symptomatic accessory navicular in the young dancer and potentially effective nonsurgical treatment options for this condition.