Measurement of Turnout in Dance Research a Critical Review

Review Article

Measurement of Turnout in Dance Research A Critical Review

Lowry M. Champion, M.F.A., and Steven J. Chatfield, Ph.D.

Abstract procedure for assessing total turnout; rotation. Turnout measurement procedures, adoption of conventions for reporting Dance aesthetics often demand results, and reporting formats vary in data in compatible forms; and the de- what is considered “perfect TO,” with- dance medicine and science research, velopment of normative data sets for out regard to anatomical capabilities making comparisons difficult. It different categories of dancers. and limitations. Perfect turnout re- is agreed that turnout results from quires 90° of external rotation of each summative contributions of the he term “turnout” (TO) is extremity, establishing a 180° angle hip, knee, lower-leg, and the foot- commonly used in dance to between the longitudinal axes of the 1,3,5,8,11,12 ankle complex. However, the most denote external rotation of feet. This is a phenomenon Tthe lower extremities; in particular, that is anatomically and biomechani- frequently reported measurement is 1,12,15 hip external rotation, and even this is ballet uses a foundation of five turned cally uncommon. Of the desired measured in incompatible ways. No out positions of the feet: first, second, 90° of perfect unilateral external 1,2 normative data exist for component third, fourth, and fifth positions. rotation, the research suggests that a and summative measures or for dif- However, the term has many associa- range of 60° to 70° is contributed by ferent categories of dancers, making tions, and an operational definition the hip, while the distal aspects of the screening, clinical assessment, and has yet to be established. Some re- lower extremity contribute approxi- 2,4,12,16-18 research problematic. Thus, there searchers define TO as external rota- mately 10° to 35°. Findings by 19 is a need to standardize component tion of the legs such that the longitu- Hamilton and colleagues and Khan 6 measurements, develop an inclusive dinal axes of the feet establish a 180° and associates support the concept of 1-10 measurement procedure for total angle. One study further defines distal contributions by reporting that turnout, and establish normative data three distinct subcategories: “techni- approximately 40% of TO originates for each measurement and for differ- cally correct,” “functional,” and “com- from below the knee. These findings 1 ent categories of dancers. This review pensated” TO. “Technically correct” emphasize the need for a total TO evaluates the 24 published articles TO is the position, as determined by measurement inclusive of all compo- that have reported original data for dance instructors, in which the hips nents. turnout assessment in dancers. Results are maximally rotated externally and The degree of total turnout (TTO) are summarized and displayed for each weight is centered through the knee accessible during functional move- article. In conclusion, recommenda- and ankle. “Functional” TO is the ment is different between individu- tions are made for: use of selected hip position assumed by the dancer, and als, and is affected by several factors, external range of motion and tibial “compensated” TO is determined by including soft tissue and skeletal 2,5-7,15 version measurements as the most the difference between “functional” anatomy. While soft tissue char- important components of turnout; a TO and bilateral passive hip external acteristics (including ligamentous laxity, muscle stretch, and muscle strength) influence TO, the scope of Lowry M. Champion, M.F.A., is at Stanford University, Palo Alto, California. this review is limited to skeletal influ- Steven J. Chatfield Ph.D. is in the School of Music and Dance, University of ences. Skeletal features influential in Oregon, Eugene, Oregon. TTO include the following: orienta- Correspondence: Lowry M. Champion, M.F.A., P.O. Box 311 Burlingame, tion and depth of the acetabulum; California 94011; [email protected]. shape of the femoral neck; degree of

121 122 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science femoral version; and degree of tibial determined that there was less agree- external rotation (HER) data reported version. ment with regards to the assessment by 17 dance-specific studies are listed The hip is a ball and socket joint, of turnout than anticipated. It was in Table 1. Table 2 lists data reported the “ball” referring to the head of the presumed that this would be an op- by the 12 studies that assessed non-hip femur and the “socket” to the acetabu- portunity for the international dance components of turnout (NHCTO). lum. Orientation and depth of the medicine and science community to Table 3 lists data generated by the 15 acetabulum influence the degree of reach a consensus on the measurement studies that reported measurements available TTO.2,10,15 A retro-oriented of turnout, with the goal of standard- of TTO, a measurement inclusive of acetabulum results in greater appear- izing assessment in the near future. It both hip and non-hip components. ance of TTO, while an ante-oriented was quickly determined, however, that The names of authors, the year of acetabulum limits the appearance of this was too large an endeavor to be publication, and a brief description of TTO. A shallow acetabulum allows completed at the time. the sample, measurement procedure for greater hip joint mobility, while Ultimately, the task of performing (including type of motion, testing a deep acetabulum provides greater a detailed and critical review of re- position, and instrumentation or cal- hip joint stability and limits external lated literature evolved to the current culation), sorting variables, and results rotation. authors. Searches were conducted of are included in each table. Studies are The length and shape of the femo- internet databases, bibliographies, catalogued in more than one table if ral neck influences hip range of and reference lists for related research values for more than one measure- motion (ROM) by determining the that generated and published original ment were reported. Evaluation of point at which the neck contacts the data on TO measurement in dancers. these reports will proceed through a acetabulum during external rotation.20 Relevant studies of dance screening brief description of each measurement Long concave femoral necks permit and the assessment of tibial version procedure. increased external rotation ROM in non-dancers were also referenced. of the lower extremity before bony Various methods used to assess TO Hip External Rotation: Table 1 contact with the rim of the acetabu- have unfortunately provided incom- Methods of assessing HER varied. lum occurs. Conversely, shorter and patible and sometimes non-applicable Three positions were used: 1. prone less concave necks decrease external data. While it is generally agreed that with hip extension and knee flexion, rotation of the lower extremity by al- TO results from summative contribu- 2. supine with hip extension and lowing less TO before contact occurs tions of the hip, knee, lower-leg, and knee flexion, 3. sitting with hip and with the acetabular rim. the foot-ankle complex,7,8,11,12,19,20,35 knee flexion. In addition, one study Femoral version is a normal twist clinical measurements of TO often described a unique calculation for in the shaft of the femur. The typi- assess only external rotation of the active “external rotation lag.” A brief cal adult human femur is anteverted hip,36-38 despite research indicating description of measurement methods 6° to 15° along the longitudinal significant contributions of non-hip and results follows. axis.2,4,10,12,21,22 Decreased femoral components ranging between 30% anteversion, or the unusual presence to 48%.6,19,39 Prone: Hip Extension and Knee of femoral retroversion, increases the The purpose of this review is three- Flexion appearance of TTO.7,12,20 fold: to catalogue published reports on Nine studies assessed passive HER Tibial version (TV) is a normal TO in dancers and describe methods (PaHER) in the prone position, with twist in the shaft of the tibia along the of measurement; to evaluate and dis- hip extension and knee flexion, while longitudinal axis in a retroverted direc- play the results; and to make recom- none assessed active HER (AHER) in tion.21,23-28 Average values as reported mendations for future assessment and this position. Variable instrumenta- for samples of the general population research. tion was used: 1. standard goniom- range from 10° to 42°.21,22,24,26-31 Av- eter, as suggested by the American erage values of 10° to 28° have been Literature Review Academy of Orthopaedic Surgeons; reported for samples of dancers.19,32,33 At the time of this review, 24 articles 2. standard goniometer, modified However, normal values ranging from that generated original data on the with a level; or 3. inclinometer. Four 0° to 20° have been referenced in the measurement of TO in dancers were studies are described in further detail dance literature.4,12,15,16,18,20 located (additional procedural articles below: the two studies that reported were found, but are not evaluated the lowest and highest values using a Relevance because they did not report original goniometer, the one study that used This review was initiated in response data). A template was devised during a modified goniometer, and the one to an interactive panel at the 2005 the review process to record specific study that used an inclinometer. International Association for Dance information and to manage inconsis- Standard goniometers were used in Medicine and Science annual confer- tencies in the literature (Fig. 1). Re- seven studies to measure PaHER in ence in Stockholm, Sweden.34 On sults were sorted by measurement, and the prone position.1,14,19,36-38,40 Subjects that occasion the panel of experts are displayed in Tables 1, 2, and 3. Hip ranged from young ballet students to Journal of Dance Medicine & Science • Volume 12, Number 4, 2008 123

Author(s): Title: Source [Journal Volume(Issue): Pages, Date.]: Objective: Relevant Assessment: HER___ NHER___ TTO___ Definition(s) of Turnout: Subjects: N: ___ Genre: Level: Students ___ Pre-Prof Students ___ University ____ Professional ____ Age: Range ___ Mean ___ Gender: Female___ Male____ Mixed____ Age at training inception: ___ Dance Experience: ____ Dance Hours / Week: ___ Protocol: Investigators: # Administrators___ # Assistants____ Trials: ___ Time of day: ___ Warm-up: yes___ no___ NP___ Description: HER: Type: Passive___ Active___ NP___ Positions: (F: Flexed, E: Extended, 90: measured at 90°) Prone___ Hip___ Knee___ Supine___ Hip___ Knee___ Sitting___ Hip___ Knee___ NP___ Extremities: Right___ Left___ Dominant___ RL___ NP___ Instrumentation: Standard Goniometer___ Adapted Goniometer___ Inclinometer___ Other___ NP____ Procedure: Method Cited: ______Corrective / Stabilization Measures: Yes___ No___ NP___ Description: Results: NHCTO: Type: Passive___ Active___ NP___ Positions: (H: Hips, K: Knees, F: Flexed, E: Extended, 90: measured at 90°) Prone____ Supine____ Calculated___(equation:______) NP___ Extremities: Right___ Left___ Dominant___ RL___ NP___ Instrumentation: Standard Goniometer___ Adapted Goniometer___ Inclinometer___ Other___ NP___ Procedure: Method Cited: ______Corrective / Stabilization Measures: Yes___ No___ NP___ Description: Results: TTO: Measurement: Passive___ Active___ NP___ Positions: (H: Hips, K: Knees, F: Flexed, E: Extended, 90: measured at 90°) Supine___ Standing 1st____ 2nd___ R3rd___ R4th___ R5th___ Calculated____(equation: ______) Other: ____ NP___ Extremities: Right___ Left___ Dominant___ RL___ NP___ Instrumentation: Standard Goniometer___ TO Protractor___ Tracing____ Calculated___ NP___ Procedure: Method Cited: Corrective / Stabilization Measures: Yes___ No___ NP___ Results: Conclusions: Notes / Literature Review: Comments:

Figure 1 Article review template. 124 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science Results: Mean Degrees (rounded) 46 45 38* 45 43 45 47 47 49 49 53 50 51 47 79 32 49 50 99 52 52 49 49 43 41 84 45 43* Variable Left Prone Age 10 Age 11 Age 12 Age 13 Age 14 Age 15 Age 16 Age 17 Age 18 Age 19 Left RL Sum Female Left Female, Left Male, Right Male, Left 39 Left 39 RL Sum 41 Sitting, Left Prone, Right Prone, Left 35 61 59 Injured, Left Non-injured, Right 49 Non-injured, Left 47 47

R A Su NA R A Su NA RL Mean RL Sum Mean Sum

I I R, L, Pa Pr Right I calculation (A/Pa)

HER G R, L Pa Pr Right HER G RL NP Pr Male Measurement Intrumentation/ Side Motion Position Sorting Sample: N; Level; Gender; Age Female; 31 Female; 9-19 Female ; 14-25 22-41 Mixed; Female; 10 18 Mixed; 18 Mixed; Instructor 30; University 16-50 & Student; Mixed; HER G R, L Pa Pr Injured, Right 47 et al. 1992 W. 28; Professional; Hip External Rotation External Hip

Study Bauman et al. 1994 Bennell et al. 1999 14; Professional; 77; Student; Female; 10 HER Garrick & Requa 1994 591; Pre-Professional; HER G Gilbert et al. 1998 Hamilton, D. et al. 2006 64; Pre-Professional; RL 20; Student; Female; 11-14 Pa HER HER Pr AdG RL Sum Pa Age 9 Pr NA Bennell et al. 2001 53; Student; Female; 11 HER Hamilton, Kadel et al. 2005 Khan et al. 1997 43; Pre-Professional; 66; Pre-Professional; Khan et al. 2000 HER LiGreci-Mangini 1993 HER 48; Pre-Professional; 15; Professional; Female; 24 HER G AdG HER R, L G R, L AdG Pa A R, L R, L, Pr P A Su Si & Pr Right Su Right Female, Sitting, Right 39 Right 35 Coplan 2002 et al. 1989 DiTullio 30; Student; Female; 14-18 HER G Do Pa Si & Pr Sitting Table 1 Table Journal of Dance Medicine & Science • Volume 12, Number 4, 2008 125 - 45 45 41 47 49 31 30 31 36 92 91 62 66 31 25 Demi-plié Dancers, Advanced 68% of 159 Demi-plié Dancers, Beginner Straight Leg 55% of 108 Dancers, Advanced 52% of 136 Straight Leg Female Male Sample Total Female Male Sample 47 Total Female Male Sample 31 Total Female Male Sample 32 Total Female Male Sample 92 Total Female Male 63 Female Male Age 17-19 Sample Total 84 89

L L R Pa Su Sample Total 45 R A RL Sum Pa RL Sum A -A HER Rotating Disks

TO Protractor, NP A Sg Dancers, Beginner 70% of 131 H ER Lag HER / Pa NA RL Sum NA NA Sample Total 30 Female;NP Advanced; contributions Photographs, &

18-22 Mixed; Female; 15.4 1988 Atwater 21; Beginning *Data *Data extrapolated from figures. AAdG (Active); (AdaptedGoniometer); Do (Dominant); ER (ExternalRotation); ER LagExternal (Active Rotation Lag); G (Goniometer); HEREx (Hip ternal Rotation); I (Inclinometer); R L (Prone); Pr (Right); (Left); (Range (Passive); ROM NA of Pa Applicable); (Not NP Sg Motion); Provided); (Not Si (Standing); (Sitting); (Supine); Su (TO) Turnout

et al. 1998 Livanelioglu 40; Student; Female; 15 Meinel & HER G et al. 2005 Negus RL Mean 29; Pre-Professional; A ER ROM NP G NA Reid et al. 1987 30; Pre-Professional; HER AdG NP Pa Si Age 13-14 76 126 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science professional ballet dancers. Results ranged between 41° and 49°, while study an AHER mean of 32.3° ± 12.5° varied from means of 38° to 61° in mean AHER measures ranged from was noted. The second study aimed to unilateral measurement.36,38 30° to 45°.8,45 evaluate change in AHER over time.45 DiTullio and coworkers evaluated In the only study to assess both These authors recorded a mean value PaHER in dominant lower extremi- PaHER and AHER, Negus and as- of 45° for right AHER from a sample ties.36 Thirty female ballet students sociates used a standard goniometer of 53 dancers, mean age of 10.7 ± (14 to 18 years of age, mean age and while measuring subjects in the su- 0.8 years, who had participated in the standard deviation not reported) were pine position with hip extension and previous study. measured. Data were not explicitly 90° of knee flexion.8 A total of 29 noted. A bar graph indicated an aver- subjects were assessed, 24 female and Sitting: Hip and Knee Flexion age value of 38° for PaHER in the 5 male. All subjects were described A third method used to measure HER prone position, a value lower than as pre-professional ballet students, assessed subjects in the seated position those reported in other studies. Lim- 15 to 22 years of age, with a sample with 90° of hip and knee flexion. Four ited description of methods prevents mean of 18 years (no standard de- studies used this method with either a speculation on factors contributing to viation reported). Passive and active standard goniometer or a goniometer the relatively low values obtained. measures were assessed with the axis modified with a level.36,38,46,47 Both Pa- LiGrecci-Mangini assessed passive of the standard goniometer placed on HER and AHER were assessed. Mean hip ROM in a sample of 15 profes- the tibial tuberosity, the moving arm unilateral PaHER results ranged from sional female ballet dancers.38 Mean aligned with the longitudinal axis 35° to 45°, while a mean of 45° was age of subjects was 24 ± 1.5 years. of the lower leg, and the stationary reported for AHER.38,46,47 Relatively high results, means of 61° arm vertically aligned with the table Reporting the lowest value for and 59° for right and left sides, were leg. The authors reported right, left, PaHER measurement, LiGrecci- reported. and summative (bilateral) means for Mangini evaluated 15 professional Using a standard goniometer AHER and PaHER found in female, female dancers in the seated position modified with a level, Gilbert and male, and both (group mean) samples. using a standard goniometer.38 The colleagues assessed 20 female ballet Mean AHER values ranged between mean age for subjects in this study was students.3 The stationary arm of the 30° and 36°. Mean PaHER values (the 24.4 ± 4.45 years. A unilateral value of goniometer was vertically aligned with only values reported in this review for 35° was reported from the average of the bubble level, and the moveable PaHER assessment in the supine posi- right and left mean PaHER values. arm of the goniometer was placed tion) ranged between 41° and 49°. Reid and associates reported values along the tibial shaft. Subjects were Two studies reported using a stan- from a level-adapted goniometer to 11 to 14 years old, with a mean age of dard goniometer that was modified better establish true horizontal and 12.35 ± 1.18 years. A mean right and with a level, in supine position, with vertical positions of the stationary left summed value of 79.4° of PaHER hip extension and knee flexion.6,44 arm.46 Subjects were 13 to 19 years was reported. Khan and colleagues measured AHER old, with a mean age of 15.4 years. Using a digital inclinometer at- in right and left hips.6,44 The moving These researchers reported mean val- tached to the tibia, Hamilton and arm of a standard goniometer was ues of 76° ± 20.1° for 13 to 14 year old colleagues evaluated 64 female ballet placed on the anterolateral margin of subjects, 89° ± 5.9° for 17 to 19 year dancers.42 Subjects were between 14 the tibia below the tibial tuberosity. old subjects, and a combined mean of and 25 years of age, with a mean age of It was reported that the addition of a 84° ± 16.2° for all 30 dancers in their 18.16 ± 1.80 years. These researchers level was advantageous when paired study. reported mean values of 48.8°, 49.9°, with the goniometer to better establish In a study designed to evaluate and 98.7° for right, left, and summed true vertical. The angle between the the effects of classical ballet training measurements. anterolateral margin of the tibia and on the lumbar region of the spine, vertical was measured while subjects Livanelioglu and coworkers were the Supine: Hip Extension and Knee performed maximal AHER. Results only group to report AHER mea- Flexion ranged from a mean of 39° in the ini- sures.47 Measurement procedures were Five studies measured HER in the tial study to a mean of 43° in the fol- not described; however, it is known supine position with hips extended low-up study on the same subjects. that a standard goniometer was used. and knees flexed 90° over the table Bennell and coworkers published These researchers referenced tech- edge.5,6,8,44,45 PaHER and AHER two studies on the measurement of niques used by Reid and colleagues46 were assessed using one of the fol- AHER assessed in the same posi- and noted one difference: Reid as- lowing instruments: 1. a standard tion as Khan and colleagues, using sessed PaHER. It was determined that goniometer; 2. a standard goniometer an inclinometer.5,45 Their first study Reid and colleagues assessed HER in modified with a level; or 3. an incli- assessed the right hip of 77 female the seated position. Thus, it is inferred nometer. Mean unilateral measures ballet students ages 8 to 11 with a that Livanelioglu and coworkers as- across these five studies for PaHER mean age of 9.6 ± 0.8 years.5 In that sessed subjects in the same position. Journal of Dance Medicine & Science • Volume 12, Number 4, 2008 127

Livanelioglu and coworkers measured ballet dancers, and university dancers pensated TO” (CTO). Mean bilateral AHER in 40 female students, 12 to 19 were assessed. Mean results across the results across the studies were 5° to years of age, with a mean age of 15 ± studies ranged from 7° to 33°.32,33 The 90°.1,8 2 years. A mean of 44.97° of AHER studies that reported the lowest and While investigating the relation- was reported. highest values are described below. ship between TO and injury, Coplan Baillon and colleagues assessed assessed CTO among 3 male and 27 Active External Rotation Lag TV in female dancers, both students female university instructors and stu- Negus and colleagues calculated three and professionals, using a dupuis tro- dents.1 Subjects were 16 to 50 years TO variables in an effort to relate val- pometer.32 Subjects were between 15 of age, with a mean age of 22 years ues to function.8 They termed the first and 40 years of age (mean or standard (injured men 20 ± 0, range 20 to 20; value “active external rotation lag” (ER deviation of age not provided). Three non-injured men 27 ± 7, range 20 to lag), and defined it as the difference samples were evaluated and means 34; injured women 19.7 ± 1.6, range between active and passive measure- were reported as follows: 25.20°, 16 to 22; and non-injured women ments of HER. Their second variable 23.46°, and 33.33°. The first sample 23.8 ± 8.7, range 16 to 50). CTO was was termed “compensated TO,” and was comprised of dance students, calculated as the difference between the third was termed “functional TO.” the second and third of professional the active functional TO angle (FTO, The second and third measurements dancers. These results are almost triple a bilateral TTO measurement acquired are not directly related to HER, and those reported by Hamilton and col- by tracing the feet while standing in are discussed under the sub-headings leagues. first position) and bilateral PaHER “Non-Hip Components of Turnout” Nemecek and Chatfield briefly (CTO = FTO - RL Sum PaHER). In and “Total Turnout.” discussed data collected from a Dance this study, 21 of the 30 subjects were Unique to the Negus study is Kinesiology flexibility laboratory in found to demonstrate CTO. Mean the concept of “active ER lag.” This the Proceedings of the 14th Annual values of 25° in the injured dancers variable determines the difference IADMS conference.33 During this and 5° in the non-injured dancers produced by passive and active HER lab 22 female university dancers (age were reported for CTO. These results methods of measurement as the dif- data not provided) assessed their own suggest a positive correlation between ference between summed right/left flexibility and the flexibility of their CTO and injury. supine PaHER measurements and colleagues via an array of methods, Negus and associates used a varia- summed right/left supine AHER which were not described. Mean val- tion of the CTO equation provided measurements [Active ER lag = (R + ues of 12° and 7° for respective R and by Coplan in their study to inves- L PaHER) - (R + L AHER)]. L TV were reported. tigate the relationship between TO A value of 29.6° was reported for and lower extremity injuries in 29 this sample. These findings indicate Indirect Measurement pre-professional ballet students.8 Sub- that bilateral AHER was approxi- In the only study of foot progression jects included 24 female and 5 male mately 30° less than bilateral PaHER. angle (FPA), Solomon and cowork- dancers who were 15 to 22 years old, Therefore, a unilateral AHER lag of ers assessed a sample of 103 female with a mean age of 18 years (standard approximately 15° was reported. dancers between 7 and 19 years of deviation not provided). Contrary to age (mean and standard deviation Coplan’s method of subtracting pas- Non-Hip Components of not provided).48 FPA is often defined sive HER from active FTO, Negus Turnout: Table 2 as the difference between the long and associates considered active HER Researchers1,6,8,9,19,20,33,44 suggest the axis of the foot and the line of pro- measurements (i.e., CTO = FTO need for evaluating TO in dancers by gression. This measurement includes angle - combined AHER). They as- including measurements of TO com- contributions of the femur and tibial sessed dancers in first, R fifth, and ponents, such as hip external rotation version during gait.22,31,41,49,50 A mean L fifth positions. Mean values across and tibial version (TV). Of the studies of 16.14° ± 4.32° was reported, a value different stance positions included a evaluated in this review, 10 assessed consistent with the afore-mentioned range of 57.8° to 89.5° of CTO. The various components of TO not derived TV measures and with the normal lowest value represented males stand- from the hip.1,5,6,8,19,32,33,40,44,48 Non-hip FPA range of 0° to 20°.22,31,41,49 ing in first position and the highest components of turnout (NHCTO) females standing in R fifth. data were obtained from direct mea- Calculations surement, indirect measurement, or Six studies derived NHCTO from Total Turnout: Table 3 calculations. original equations.1,5,6,8,40,44 NHCTO Total turnout (TTO) is a measure- was calculated in each study by sub- ment inclusive of contributions by Direct Measurement tracting HER from a standing TTO the hip, knee, lower-leg, and the Three studies measured NHCTO measurement. Calculations were foot-ankle complex.20,34 This mea- directly using a version of the goniom- termed “below-hip ER” (BHER), surement has also been referred to as eter.19,32,33 Ballet students, professional “non-hip ER” (NHER), and “com- “turnout” (TO),39,42,51 “turnout angle” 128 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science 71 Results: Mean/ Range (rounded) 33 18 8 25 13-17 11 10 46 37 37 58 90 74 89 72 12 7 11 19 18 19 19 V Dancers, Advanced 32% of 159* Female Group Non-injured 5 Female Male Demi-plié Dancers, Beginner Straight Leg of 108* 45% Dancers, Advanced 48% of 136* Straight Leg Male Sample Total Female Male Sample Total 87 Female Male 86 Left Ages 7 & 8 Age 9 Age 10 Age 11 9 Age 12 Age 13

E/f; K E/F R, L NA Right A A A RL Sum NA Sample Total 69 A HER) RL Sum A HER) RL Sum NA NA Female NA AHER AHER R R NA NA NA NA

G RL Mean NP Male NP Dupuis RL NA Group III 25 Protractor Protractor, Footprints, tropometer Mean Group IV 23 calculation (Pr/Su; H Variable Pedals Foot HER (R+L) HER (R+L) HER (R+L) HER RL Pa Friction-free – R ATO – R ATO TO Quantified from RL Sum Standing Dancers, Beginner 30% of 131*

angle - R Fifth St FTO angle - L Fifth St FTO TV CTO angle - First St FTO contributions Photographs, (HE; KF) Demi-plié Measurement Intrumentation/ Side Position Sorting Advanced; A NH Female; NP

18-22 Mixed; 14, Professional, 18-40 21, Professional, 18-30 Sample: N; Level; Gender; Age Instructor 30; University 16-50 & Student; Mixed; CTO 22-41 HER - RL Pa FTO 18 RLSum NA Injured Non-Hip Components of Turnout Components of Non-Hip 1988 Atwater & 21; Beginning W et al. 1992 28; Professional; Mixed; TV

Study Baillon et al. 1983 Bennell et al. 1999 15, Student, 15-20 Bennell et al. 2001 Coplan 2002 77; Student; Female; 10 Gilbert et al. 1998 53; Student; Female; 11 Hamilton NHER NHER 20; Student; Female; 11-14 Khan et al. 1997 R Khan et al. 2000 R NP Meinel & 18 66; Pre-Professional; Mixed; BHER 48; Pre-Professional; Mixed; LLER - (R+L angle - ATO BHER RL Sum LLER - (R+L RL Sum et al. 2005 Negus NA Pre-Professional; 29; Nemeck & Chatfield 2004 Female; NP 22; University; Solomon et al. 1994 TV 103; Student; Female; 7-19 FPA Quantified from RL Mean Gait Sample Total 16 Table 2 Table Journal of Dance Medicine & Science • Volume 12, Number 4, 2008 129

(TO angle),3,9 “turnout range” (TO this value is converted to a comparable range),5,45 “lower-limb external rota- unilateral mean of 65° using a sagittal tion” (LLER),6,44 and “functional TO rather than coronal reference. angle” (FTO angle).1,8 In addition, Kadel and colleagues applied two some studies have reported inclusive methods for assessing hip external

18 18 14 TTO measurements as “hip external rotation.40 The first qualified as HER, rotation”52,53 and “hip external rota- the second as TTO assessment. The tion flexibility.”40 second measurement, originally Across these studies TTO has been used by Nicholas, assessed externally assessed in several ways, including: rotated stance in the ballet first posi- 1. subjects standing in first position.54 Nicholas defined this flexibility tion on an original protractor;5,6,44,45 test as a measurement of total leg TO. 2. measuring lines constructed on Subjects stood heel to heel, externally tracings of feet in different ballet rotated both lower extremities to the positions, including first, first demi- maximal degree, and the angle created plié, first after landing from jumping, by the feet was recorded.54 Kadel and second, third, fourth, R/L fifth, and colleagues used a goniometer to mea- Age 14 Age 15 Age 16 Ages 17 & 19 14 R/L fifth after landing from jump- sure the angle between the long axes ing;1,3,8,9,42,51,52 3. measurements of of the two feet. A bilateral mean of TTO from photographs of subjects 174.09° ± 4.65° was reported for the standing on friction-free foot ped- sample of 43 female pre-professional als;39 4. the Nicholas lower extremity ballet students with an average age

torque flexibility test;40 and 5. using of 10 years. These findings represent the Leighton Flexometer with the the greatest TTO measures in this subjects in the seated position.53 review. The first four in the above list mea- The only study of passive TTO, by sured active TTO, while it is unknown Nemecek and Chatfield, reported R/L whether the fifth measured passive or measures of 53° and 43° degrees.33 A

active TTO. Of the studies included variety of approaches were used to as- in this review, 13 reported original data sess TTO; however, no methods were on active TTO,1,3,5,6,8,9,39,40,42,44,45,51,52 one described in the publication. study reported original data on passive In a unique study, Negus and TTO,33 and one study was undeter- coworkers evaluated static, dynamic, mined.53 Reported mean values ranged and static-dynamic TO discrepancies.8

from 25° to 174° for assessment of These researchers approached the as- active TTO, while passive TTO results sessment of TO through tracing the had a much narrower range of 86° to feet. Functional TO angle (FTO) was 106°.33,40,51 Six studies are described in determined for 24 female and 5 male greater detail below. Included are the pre-professional dancers (age 15 to studies that: 1. reported the lowest TTO 22 years, mean 18 years) utilizing the measure, 2. reported the highest TTO following protocol: feet were traced measure, 3. assessed passive TTO, 4. in first, R fifth, and L fifth positions investigated static and dynamic discrep- (static); subjects were instructed to ancies, 5. used friction-free foot pedals, perform three jumps, and the feet and 6. used the Leighton Flexometer. were retraced (dynamic); lines from Winslow and Yoder randomly se- the heel midpoint through the second lected 10 subjects (age not provided) toe were used to establish longitudinal

from the 24 females in their study to axes of the feet, and the angle created measure the angle of TO.51 The angle by the intersection of longitudinal axes between the frontal plane and a longi- was measured. Mean static measures tudinal line through the dancer’s foot ranged from 123.8° (first position, was established, but the procedure males) to 151.2° (right fifth, females). for doing this was not described. A Mean dynamic measures ranged from unilateral sample mean of 25° was 114.3° (first position, males) to 148.4° reported using a coronal reference (R fifth, females). Considering the line. To make this value comparable dynamic aspects of dance, the authors * Derived from data provided for hip contributions; A (Active); BHER (Below Hip External Rotation); CTO (Compensated Turnout); ER (External Rotation); FPA (Foot Progression Angle); Progression (Foot FPA Rotation); (External ER Turnout); (Compensated CTO Rotation); External Hip (Below BHER (Active); A contributions; hip for provided data from Derived * G (Goniometer); HE (Hip Extension); Turnout); HER (Functional FTO (Hip External Rotation); HF (Hip Flexion); KE (Knee ROM (Right); Extension); R KF (Prone); (Knee Flexion); L Pr (Left); LLER (Passive); (Lower Leg Pa Provided); (Not NP Rotation); External (Non-Hip NHER Turnout); of Components (Non-Hip NHCTO Applicable); (Not NA Rotation); External Version) TV (Tibial (Turnout); TO (Supine); Su (Sitting); Si Sg (Standing); (Range of Motion);

to all of the other studies in Table 3, also calculated the difference between 130 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science Results: Mean Degrees (rounded) 46 47 93 53 52 105 119 62 60 122 Dancers Fifth Position, RF 95 Male Left 55 Subject 4 Subject 5 Subject 6 93 81 62

St/Dy) K: E/F) (HE; KE) (HE; KE) RL Sum RL Sum (HE; KE) First (HE; KE) RL Sum 3 Subject Subject 2 71 83 First (HE; KE) Male Right Female Left 59 62 RL Sume First Left

the foot angle of (HE; KE) angle of First, Second Position Second 97 longitudinal (HE; KE) longitudinal Non-Injuried 100 longitudinal Third, Fourth Third Position, RF 93 tracing of feet tracing of feet Angle of angle of First Dancers Angle Goniometer; RL Sum A Standing: First Position 94 bisection on paper Measurement of bisection on paper First bisection of feet on paper tracing rotation demonstrated KE) (HE; by the long axis of Position, RF Fourth 94 (HE; KE) Range Range Protractor RL Sum Protractor RL Sum First First L L Description Method (A/Pa, (H: E/F; Variable Measurement/ Intrumentation/ Side Motion Position Sorting Sample: N; Level; Gender; Age Female; 10 Female; 11 Instructor & Student 22 Mixed; Turnout Female; 14-25 18 Mixed; Female; NP Female; 11-41 Female; 10 Flexibility* 18 Mixed; of external degrees First Total Turnout Total

Study Bennell et al. 1999 77; Student; Bennell et al. 2001 53; Student; Coplan 2002 Turnout Turnout 30; University Turnout Functional Turnout R, L, NP; Measurement A Hamilton, D. et al. RL Sum et al. 2006 R, L, A 64; Preprofessional; Standing: A Turnout Standing: R Standing: Goniometer; Injured RL Sum R A Standing Khan et al. 2000 First Position Martin et al. 1998 48; Pre-Professional; LLER 136 6; Professional; protractor Turnout R, L, HER* A Goniometer Standing: Do Right A Standing: Subject 1 82 Gilbert et al. 1998 20; Student; Turnout Kadel et al. 2005 43; Pre-Professional; HER Khan et al. 1997 66; Pre-Professional; Goniometer; LLER RL Sum protractor A Turnout R, L Standing A First Position Standing: 136 Female Right 63 Table 3 Table Journal of Dance Medicine & Science • Volume 12, Number 4, 2008 131 48 133 124 130 114 151 140 148 134 151 146 130 50 49 53 43 147 146 65† Plié Dancer; Advanced Plié 159 Dancer; Beginning 180 Straight Leg Dancer; Advance Straight Leg 136 Left Right Left

A, St Standing: A, Dy (HE; KE) Standing: sample Total R Fifth (HE; KE) Male A, St sample Total Standing: 149 R Fifth Female A, Dy (HE; KE) Male Standing: 146 sample Total L Fifth Female (HE; KE) Male A sample Total 149 L Fifth Pa Female (HE; KE) Male, Static Pa 143 Female Male 138 with reference to with a reference Dy (Dominant); coronal A Do measurement; (Dynamic); (Active); ER (External °

Angle NP A Standing: NA NP R, L A NP Right Angle of RL Sum A Standing Plié: R Fifth Leighton R, L NP NP NA Protractor, plane and a Pedals Foot Friction-free tracing of feet First Female ballet position (He; KF) both feet in the L Fifth NP flexometer; Angle NP; from Photographs, of feet on paper A, Dy Standing: sample Total 128 feet measured on a paper tracing of Standing Plié: (HE; KF) L Fifth between the frontal longitudinal line through the foot Angle longitudinal axes (HE; KE) Male Young, Turnout NP; Advanced 21; Beginning Female; NP Turnout Quantified Female; 16 RL Sum A Standing: Dancer; Beginning 31 22; University; TTO Preprofessional, University, Professional; 11-25 Mixes; Angle 10; University; reference lines of Turnout R Fifth 18-2 Mixed; Turnout Bisection of First Female

1995 Yoder Female; NP *Referenced as HER in study, follows TTO criteria; †this TTO value has been converted from 25 follows as HER *Referenced in study, Provided); (Not NP Applicable); (Not NA (Left); L Flexion); (Knee KF Extension); (Knee KE Flexion); (Hip HF Rotation); External (Hip HER Extension); (Hip HE (Goniometer); G Rotation); Turnout) (Total TTO (Turnout); TO (Static); St (Range of Motion); R (Right); ROM (Passive); Pa Meinel & 1988 Atwater & Micheli 1984 25; Pre-Professional; HER* Nemeck & Chatfield 2004 Female; NP 1989 Watkins 350; Winslow et al. 2005 Negus 29; Pre-Professional; Functional Goniometer; RL Sum A, St Standing: sample Total 131 & 132 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science static (St) and dynamic (Dy) func- of the pointer on the dial measures the In 1965, the AAOS published Joint tional TO angle (StDy difference = St arc through which the movement has Motion: Method of Measuring and FTO angle - Dy FTO angle), yielding passed; knee and ankle joints remain Recording,43 which was approved by a mean difference of 2.6° (first posi- locked and hips should not shift.55 several international orthopaedic as- tion, females) to 9.5° (first position, Based on information provided by sociations. This project initiated the males). Micheli and Leighton, it is unknown fulfillment of requests to standardize Meinel and Atwater presented a whether this procedure assessed pas- methods of measuring joint motion. brief description of their investiga- sive or active TTO. Data were cata- These requests parallel our call for tion intended to quantify component logued accordingly and an average of standardization of the measurement of contributions to TTO.39 At the time 48.1° ± 6.5° was reported. TO. As a result of efforts made by the of our review, this represented the only AAOS, HER measurement protocol study to investigate TTO with sub- Discussion and has been standardized, and few varia- jects standing on friction-free discs, Recommendations tions of the recommended methods thus eliminating friction coupling. TO is assessed by approximately 95% were noted in this review. The thighs, shanks, and feet of 21 fe- of practitioners during initial screens HER measurement is affected by male ballet dancers (10 beginning and and injury evaluations, and it is one many factors.8 Each factor should be 11 advanced; age data not provided) of the most frequently researched considered during assessment, report- were attached with fins to allow mea- subjects in dance medicine and sci- ing, comparison, and analysis. These surement of each segment using aerial ence.56,57 However, some researchers factors include: 1. type of procedure: photographs. The dancers were photo- have concluded that “the ‘ultimate active or passive; 2. testing position: graphed standing in first position on truth’ concerning turnout and bal- prone, supine, sitting, or standing; 3. the friction-free discs, first in demi- let remains elusive.”37 Much of this pelvic position: degree of pelvic tilt, plié with hips and knees flexed, then can be attributed to the absence of a stabilization, and correction; 4. hip with hips and knees extended. Joint standardized measurement, not only position: degree of flexion or exten- rotations were measured and aver- for TTO (a measurement inclusive sion; 5. position of the contralateral aged for three trials in both positions. of all components) but also for the limb: neutral or abducted, and the Statistical analysis determined greater components of TO. presence of knee flexion or knee ex- TTO among both sample groups in Various methods for measuring TO tension; and 6. warm-up status of the plié compared with standing. Means have been devised. One of the primary dancer. We agree with other research- of 130.8° ± 17.7° versus 108.1° ± differences among these methods is ers that HER should be measured in 17.1° (beginning dancers standing the definition of TO. Some researchers the prone position with hips in exten- in plié versus standing straight) and define and measure TO as hip external sion and knees in 90° flexion.15,20,58,60 158.7° ± 18.0° versus 135.7° ± 15.9° rotation, while others define and mea- This position allows for both passive (advanced dancers standing in plié sure it as the sum of lower extremity and active assessment of HER. It is versus standing straight) were found, external rotation. As demonstrated important for HER to be measured indicating a 23° increase in both by this review, these methodological while the hips are extended, as this groups while in plié. differences produce different results, best reflects the functional stance The Leighton flexometer was used making comparisons difficult. On the position of the dancer and hip place- by Micheli and associates to evaluate other hand, standardizing the assessment during TTO measurement. In hip external rotation in 25 pre-pro- ment of TO would enable us to: better addition, warm-up status should be fessional ballet dancers (gender not screen and assess dancers; understand reported. specified).53 A mean age of 16 years TO and its relationships to training, (range and standard deviation not performance, and injury; and more Non-Hip Components of Turnout provided) was reported. Measure- accurately interpret and compare TO / Tibial Version ment procedures were not described research.20,34,58,59 When comparing HER and TTO in this report. The investigators cited measures a discrepancy exists: the for- an original article by Leighton, which Hip External Rotation mer results are consistently less than includes the following protocol for Hip external rotation (HER) is the the latter. This difference is accounted hip external rotation assessment: most common TO measurement for in non-hip components of turnout subject in the seated position on a reported in research. Approximately (NHCTO). Approximately half of the bench in hip flexion with knees ex- 70% of the studies included in this studies in this review reported values tended; flexometer attached to the review assessed HER. The methods for NHCTO measurements. A variety foot; contralateral foot may rest on referenced in this review for measur- of terms and definitions were noted. the floor; dial is locked when the leg ing HER reflect standard methods Tibial version, non-hip external rota- is externally rotated to the end range recommended by the American tion, compensated turnout, below-hip and the pointer is locked at the end Academy of Orthopaedic Surgeons external rotation, active non-hip TO, range of inward rotation; the position (AAOS),43 or slight variations thereof. and FPA were all used to denote a Journal of Dance Medicine & Science • Volume 12, Number 4, 2008 133

TO measurement not inclusive of knee, lower-leg (e.g., tibial version), manipulation; 5. friction coupling: the hip component. Tibial version is and the foot-ankle complex], not only increased TO by using friction from the primary non-hip component of is an efficient assessment approach for the floor when standing (except when TTO, as it can contribute up to 20° clinicians and researchers, but better standing on rotational discs);58 6. to TTO without inducing rotational reflects the concept of TO as it relates warm-up status of the dancer: activity stress at the knee.12,15 Of the 24 studies to dance.10,20 While we acknowledge and duration. reviewed, only three included original the paucity of reliable and valid meth- TV data.19,32,33 Absence of research ods, we emphasize the importance of Data Collection, Handling and on TV indicates that it is often over- using an inclusive TTO measurement Reporting looked in the assessment of dancers. in the assessment of TO. Many methods described in this A standardized procedure for Grossman20 proposes an effective evaluation of the literature have not TV measurement in the general measurement procedure for passive been tested for reliability and validity. population and in dancers has yet to TTO assessment. This procedure To reduce measurement and report- be established. Naturally, different was adapted from an inclusive HER ing error it is recommended that measurement procedures produce measurement procedure previously future studies use one trained and different results.20,22,25-27,30,33,58,61-65 Two discussed by Clippinger,10,15 Hoppen- experienced administrator and report studies of non-dancers assessed TV field,66 and the AAOS.43 It is described averages from a minimum of three tri- using different measurement proce- as follows: the subject is supine with als.9,19,27,33,63 Clinicians and researchers dures.62,63 The first reported a range hips and knees extended; the foot should use goniometeric measurement of 19° to 34°, and the second a range and ankle complexes are locked in rather than visual estimates to increase of 14°to 46°. Tibial version measure- dorsiflexion, limiting pronation; the reliability.67 Not only are goniometers ment procedure also affected calcula- entire lower extremity is externally reliable, but they are affordable, easy tions of TTO in a sample of collegiate rotated; measurement is taken at the to obtain, and non-invasive.67 modern dancers. Depending on the foot using a goniometer, one arm ver- As should be abundantly clear, TV measurement procedure used, the tically aligned and the other aligned measurement procedures and for- calculated TTO measurements varied with the center of the heel and along mats for reporting TO measures vary from 97° to 116°. Findings from the the shaft of the second metatarsal.20 tremendously. These inconsistencies above studies emphasize the need for This method is easily accessible and make comparisons across studies standardization. allows for comparison of data from difficult or even impossible. The fol- Several measurement procedures have passive HER and TV measurements. lowing principles are adapted from a been reported for TV.19-22,25-31,41,49,61-65 Although it warrants further investi- list provided by the AAOS43 and are One method, the “thigh-foot angle” gation and testing, we recommended recommended for the measurement (TFA), is an accessible and noninvasive that it be used in the assessment of and reporting of TO in dancers: 1. approach. This procedure has been dis- passive TTO. motions should be calculated from cussed and recommended by researchers To date there are no methods of a defined zero starting position, add- for the assessment of TV in dancers.18,20 active TTO measurement that have ing the degrees of joint motion in TFA has been described as the angular been tested for validity and reli- the direction the joint moves; 2. to difference between the long axis of the ability. However, several approaches eliminate possible confusion as a result foot and the long axis of the thigh, and have been investigated. As previously of measuring joint motions from dif- can be measured with a goniometer in noted, some researchers have used ferent starting positions, the extended the prone position with hip extension rotational discs to assess active TTO “anatomical position” of an extremity and 90° knee flexion.41,49 One arm of the in dancers while eliminating friction is accepted as 0°, rather than 180°; goniometer is placed along the second coupling. This method should be 3. motions should be listed as either metatarsal shaft and the other arm is further investigated and eventually passive or active; 4. hip and knee po- aligned with the tibial tuberosity. tested for reliability and validity. sitions should be described as either flexed or extended; and 5. terminology Total Turnout Important Considerations for should be clearly defined. Although researchers agree that TTO Measurement Normative values for NHCTO and is summative, this review identifies Until further research is conducted TTO do not exist. This makes screen- HER, a component measurement, and measurement procedures are ing and clinical assessment problem- as the primary measurement in the standardized, important consider- atic. Norms cannot be established evaluation of TO. This review sup- ations in the assessment of TO are: 1. until measurements are consistent and ports previous findings that HER type of motion: active or passive; 2. standard. Standardized methods of measurement is not a predictor of testing position: standing, prone or measuring HER, NHCTO, and TTO total or functional TO.3,8 A TTO supine; 3. pelvic position and degree among dancers should be simple, measurement procedure, one that is of stabilization; 4. alignment: natural inexpensive, objective, time efficient, inclusive of all contributions [hip, or corrected via verbal cues or physical and reliable. Upon standardization, 134 Volume 12, Number 4, 2008 • Journal of Dance Medicine & Science norms can be established for danc- extremity injuries in classical ballet magnetic resonance imaging. Br J ers that take into consideration age, dancers. J Orthop Sports Phys Ther. Radiol. 1997;70:575-9. gender, level of training, and genre. 2005;35(5):307-18. 22. Seber S, Hazer B, Kose N, et al. Ro- Dance-specific normative values will 9. Watkins A, Woodhull-McNeal AP, tational profile of the lower extremity enable the dance medicine and science Clarkson PM, et al. Lower extrem- and foot progression angle: comput- ity alignment and injury in young, erized tomographic examination of community, in particular researchers preprofessional, college, and profes- 50 male adults. Arch Orthop Trauma and clinicians, to better compare data sional ballet dancers: Part I. turnout Surg. 2000;120(5-6):255-8. and literature. In addition, this will and knee-foot alignment. Med Probl 23. Eckhoff DG, Winter WG. Femoral allow dance medicine and science Perform Artists. 1989;148-53. and tibial torsion. Clin Orthop Relat professionals to better screen for, as- 10. Clippinger-Robertson KS. Biome- Res. 1994;302:2-3. sess, and ultimately prevent injuries chanical considerations in turn- 24. Le Damany P. La torsion du tibia. among dancers. out. In: Solomon R, Minton SC, Normale pathologique, experimen- It is recommended that the dance Solomon J (eds): Preventing Dance tale. J l’Anat Physiol. 1909;45:598- medicine and science community Injuries. 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