The Effects of Pointe Shoes on Ballet Dancers’ Biomechanics,Muscle Activity,Movement and Symptoms: A Scoping Review

Abstract

Introduction: Dancing en pointe requires ballet dancers to stand on the tips of their toes while wearing a structured pointe shoe. Understanding the effect of pointe shoes on ballet dancers’ biomechanics, function, symptoms and skin health is essential to guide shoe development and ultimately improve dancer performance. Therefore, the purpose of this scoping review was to map the evidence and identify knowledge gaps related to the effect of wearing pointe shoes on professional and recreational ballet dancers. Method: A scoping review was conducted by searching 6 electronic databases and the International Association for Dance Medicine and Science Bibliography. Results: Thirty-five studies were grouped into 5 categories: pointe shoe factors (eg, toe box and shank, pointe shoe status; 9 studies), shoe types (eg, flat shoes vs demi pointe vs pointe; 10 studies), ballet movements (11 studies), symptoms (5 studies), and intrinsic dancer factors (eg, foot type/toe length; 7 studies). Studies were published between 1979 and 2023, with 72% (n = 23) published between 2006 and 2020. Most (86%) of the studies were cross-sectional. Most studies explored biomechanical outcomes and the most common data collection device was force plates (19 studies). Overall, there was an insufficient volume of evidence for specific research aims. Significant gaps in knowledge exist regarding functional and performance-based outcomes, injury outcomes including exploration of factors such as shoe age/usage, and pointe shoe treatment factors. Conclusions: Currently the field of research suffers from threats to ecological validity, with many study methods not reflecting ballet-specific demands or environments. The impact of pointe shoes on ballet dancers is a developing research area, and this scoping review can help guide future research decisions. Studies need to target the knowledge gaps and employ rigorous ecologically valid study designs and ensure that findings inform shoe design and dancer education to minimize injury and maximize comfort and performance.

Keywords

ankle/foot ballet biomechanics pointe dance science research methods risk factors

Key Points

Studies examining the effect of pointe shoes on ballet dancers are heterogenous in their research aims, outcome measures and methods

Significant knowledge gaps exist regarding functional and performance-based outcomes, injury outcomes including exploration of factors such as shoe age/usage, and pointe shoe treatment factors (eg, breaking in procedures and padding)

Ecological validity needs to be considered, with many studies employing methods that do not reflect ballet-specific demands or environments (eg, not assessing dancers’ own shoes)

Introduction

Dancing en pointe requires ballet dancers to stand on the tips of their toes while wearing a structured pointe shoe. Pointe shoes are traditionally composed of layers of burlap, cardboard and paper, and recent innovations have seen enhancements to improve fit, comfort and performance including rubber toe cushioning and flexible polymer shanks.^1,2 Pointe shoes are integral to ballet and allow the dancer to achieve the illusion of hovering, whilst performing graceful and esthetic movements.³ From approximately 12 years of age, pointe shoe usage can be introduced, and at the professional level, ballet dancers spend approximately 8 hours every working day wearing pointe shoes.^3,4 In general and sporting populations, shoe type and design can enhance and restrict movement and may be associated with injury risk.^5,6 Knowledge about the effect of pointe shoes on ballet dancers could be used to inform shoe design or education regarding shoe modification with the aim to maximize dance performance and minimize injury for all ballet dancers.

Anecdotally, ballet dancers of all skill levels who regularly undertake pointe work experience pain and discomfort. Many ballet dancers report blisters, bunions, and broken toenails.^7-10 Limited research has explored the shoe-related (eg, toe box or shank properties) and intrinsic dancer-related (eg, foot and toe shape) factors associated with skin lesions and discomfort.^3,11 Blisters can have a negative effect on sporting performance and duties.¹² It is likely discomfort impacts dance performance, but this is yet to be explored.

Higher ground reaction forces (GRF), and certain neuromuscular activity and lower limb biomechanical variables (eg, greater peak hip adduction in female runners) have been posited to increase the risk of injury and reduce performance in sporting populations.^13-15 Several studies have explored similar factors in relation to pointe shoes.^16-19 Given the heterogeneity among these identified pointe shoe studies, and the likelihood of additional studies, systematic collation and synthesis could assist interpretation and allow identification of knowledge gaps to guide future research.²⁰

Examining how wearing pointe shoes affects factors such as biomechanics, function and skin health is essential to inform shoe design to minimize injury and maximize performance and comfort of ballet participants globally, some who rely on pointe shoes for their livelihood. Current literature in the field is disparate and does not lend itself to systematic review or meta-analysis. Therefore, the purpose of this scoping review was to map the evidence and identify knowledge gaps related to the effect of wearing pointe shoes on professional, pre-professional, and recreational ballet dancers.

Methods

Protocol and Registration

The objectives, inclusion criteria and methods for this scoping review were described in a protocol uploaded to the Open Science Framework (https://osf.io/6sjgu/).

Eligibility Criteria

The Joanna Briggs Institute (JBI) framework for scoping reviews was followed and the population, concept, context (PCC) approach was used to develop eligibility criteria and search terms.²¹ The population for this review was ballet dancers and the concept was defined by the phenomena of interest, pointe shoes. No context was specified in this review.

Inclusion Criteria

Included studies needed to: (1) investigate one or more of professional, pre-professional or recreational ballet dancers, with no age restrictions; (2) focus on the effect of pointe shoes on dancers (including but not limited to biomechanics, function, symptoms or dance performance); (3) be available in English; and (4) be primary research studies (eg, observational, experimental). Except for studies reporting symptoms, injury or skin health, all included studies needed to analyze independent variables allowing for comparison between groups. For example, studies comparing 2 types of toe padding, or studies exploring the difference in foot biomechanical variables from wearing different dance shoe types, would have met the criteria. Inclusion of abstracts, conference proceedings and theses in addition to published peer reviewed articles fulfils the scoping review aim to map the extent of the field of science. The review excluded: (1) review studies; (2) studies in languages other than English; and (3) studies examining pre-pointe vs pointe groups or using pointe status as a variable to demonstrate effect.

Information Sources

The following electronic databases were systematically searched: MEDLINE, CINAHL, SPORTDiscus, Embase, and Cochrane Library. A grey literature search was conducted using ProQuest for data reported in theses, and the International Association for Dance Medicine and Science (IADMS) Bibliography (7th Edition) searched for additional studies. Hand-searching of reference lists was undertaken and key experts in the field were consulted.

Search Strategy

The literature search was conducted on 30th August 2020 and updated on the 13th July 2023. The Medline search strategy is displayed in Table 1. Appropriate truncation symbols, Boolean operators and MeSH terms were used for individual databases. Duplicate articles were removed using EndNote X9 (Clarivate Analytics, Boston, United States of America) referencing software. Title, abstract and full text screening was undertaken using review software (Covidence, Melbourne, Australia). Titles and abstracts were assessed for suitability based on the stipulated eligibility criteria by 2 independent reviewers (KM & KF). Where there were insufficient data provided in the title and abstract, the full text was analyzed to determine eligibility (2 independent reviewers: KM & KF). Included studies were cross-checked to ensure no duplicate datasets were included. All conflicts generated through the screening stages were discussed between 2 reviewers (KM & KF) until consensus was reached.

Table 1.

MEDLINE Search Terms.

1.	ballet or Dancing/
2.	danc*
3.	1 or 2
4.	pointe
5.	pointe shoe*
6.	Shoes/ or shoe*
7.	footwear
8.	4 or 5 or 6 or 7
9.	3 and 8

Note: *a truncation to instruct the database to search for all forms of the word. Used if supported in the various databases.

Data Charting and Extraction Process

Data charting was conducted using a data charting sheet created for this review (Microsoft Excel, Version 2102, Microsoft, Washington, United States of America). Key information including authors(s), year of publication, country of origin, information related to aims for example, pointe shoe status, study population and sample size, method, dance related outcomes for example, pain, performance or joint and body motion, and key findings were extracted and charted in a narrative table. Charted outcomes were independently sorted into categories by 2 reviewers (KM & KF) based on the aims, outcomes and methods used in the included studies to assist with interpretation of findings. Categories were discussed and modified accordingly until agreement was reached. Research aim categories typically reflect the exposure variable and include: shoe factors (eg, toe boxes), shoe types (eg, ballet flats and pointe shoes), ballet movements, symptoms and skin health and intrinsic dancer factors (eg, toe length, experience level). Knowledge gaps were reported via narrative synthesis of the studies. Data were mapped and displayed in tables and graphs and summarized using narrative synthesis.

Results

Characteristics of Included Studies

Thirty-five studies were included in this review (Figure 1).

Figure 1.

Flow chart of study identification and selection process.

Studies from 7 different countries were included, with just over a third (37%) from the USA.^{3,10,16-18,22-29} Nine percent of studies were from the United Kingdom,^30-32 3% from Canada,³³ France,³⁴ New Zealand,⁹ Egypt,³⁵ and Greece,³⁶ 6% from Japan,^19,37 6% from Taiwan,^38,39 and for the remaining 29% the country of testing was unclear.^7,8,11,40-46 Of the included studies, there were 24 journal articles, 5 theses,^{3,10,27,31,33} 4 conference articles,^18,26,41,45 and 2 abstracts.^7,28

Thirty-one studies reported the sex of the participants, all but one¹⁰ only recruited females. The level of dance experience varied, with 29% of studies involving participants reported as professional dancers, 29% university dancers, 13% advanced, 13% intermediate/experienced, 7% novice, and 7% pre-professional. The age of participants and years en pointe were poorly reported (Table 2).

Table 2.

Type of Included Studies and Age/Dance Experience of Participants.

Study	Study type	n	Sex (% female)	Dance level	Age (years) mean (SD)^	Years on pointe (mean (SD)^
Albers et al²²	CS	10	100	University	15.8	3.0 (2.9)
Aquino and Amasay¹⁶	CS	13	100	Professional	20.9 (1.9)	10+
Aquino et al²³	CS	9	100	Professional	22.2 (2.2)	11.4 (1.4)
Bickle et al³⁰	CS	15	100	Professional	26(4)	3+
Buckner³	CS	143	100	Professional	NR	NR
Chockley²⁴	CS	7	100	University	NR	NR
Clarkson et al⁴⁰	CC	23 (I) 19 (C)	100	Advanced + college students	17.8 (3.6)	5.4 (2.2)
Cox and Herzog²⁵	RCT	36	100	Ballet school novice	13.2 (2.2)	NR
Farmer³³	CS	4	100	Professional	NR	NR
Golomer and Chatellier⁷	CS	38	100	Professional	NR	NR
Hugel et al³⁴	CS	8	100	Professional	16-35	NR
Huh³¹	CS	8	100	Advanced recreational	19-26	NR
Kadel et al¹⁸	CS	4	100	Regional ballet companies	22-24	NR
Kizawa et al¹⁹	CS	25	100	Dancing 6+ years	17.4 (1.6)	NR
Kravitz et al²⁶	CS	40	NR	NR	NR	NR
Leslie²⁷	CS	1	100	Advanced ballet school	25	8
Lin et al³⁹	CS	13	100	Dancing 5+ years	19.15 (1.9)	>3
Lin et al³⁸	CC	22 (I) 11(C)	100	College ballet school	19.7 (2.4)	NR
McPherson et al¹⁷	CS	21	100	University	19.28 (1)	NR
Paderi et al³⁶	CS	13	100	NR	22.4 (2.5)	5.6 (3.1)
Pearson and Whitaker³²	CS	8	100	University	19.63 (1.06)	>2
Penitente et al⁴¹	CS	8	100	Novice + intermediate	novice 19.5 (7) intermediate 24.75 (6.2)	novice <1, intermediate 3-5
Russell et al⁸	CS	9	100	University + pre-professional	21 (2.9)	7 (4.9)
Russell et al⁴²	CS	15	100	University, pre-professional + professional	21 (3.0)	8 (4.8)
Russell et al⁴³	CS	7	100	Experienced	24	11
Salzano et al¹¹	CO	10	100	Professional	18.6 (3.8)	NR
Saleh³⁵	CS	5	NR	University	20.1 (0.7)	NR
Skrinar et al²⁸	CS	12	100	College	NR	7.75
Teitz et al⁴⁴	CS	13	100	Advanced ballet students	NR	NR
Torba et al⁴⁵	CS	1	NR	NR	NR	NR
Tsubaki et al³⁷	CS	10	NR	Amateur	21.0(2.6)	7.8(2.9)
Veirs et al²⁹	CS	11 (10 actual data)	100	Pre-professional + professional	21	NR
Wakes and Caudwell⁹	CSt	9	100	Ballet school	18+	<2 to >8
Walter et al⁴⁶	CS	18	100	University	19.94 (1.16)	NR
Zepeda¹⁰	CS	9	0	Professional	31.3 (5.8)	6.67 (7.9)

Abbreviations: NR, not reported; I, intervention group; C, control group; JA, journal article; CA, conference article; Ab, abstract; Th, thesis; CS, cross sectional; CC, case control; RCT, randomized controlled trial; CO, cross over; CSt, case study.

mean(SD) data when available, if not, other available data were reported.

Mapping the Field of Evidence

Chronological history of included articles

The year of publication of the included studies ranged from 1979 to 2023. The volume of primary literature investigating the effect of pointe shoes on ballet dancers has increased significantly in the 15 years up to 2020. Of the 32 included studies, 31% (n = 10) were published between 2016 and 2020, 72% (n = 23) from 2006 to 2020 and 9% between 2021 and 2023 (n = 3). Prior to 2006, only one or 2 studies were produced every 5 years (Figure 2).

Figure 2.

Representation of publications over time. Each square box represents one publication. The colors represent the research aim categories (common themes in the body of literature). Multiple colors in a single square box means that the study was categorized into multiple research aim categories.

There has been a recent increase in the number of studies focusing on shoe factors, with 6 studies^{3,11,16,17,23,30} being published in the 5 years to 2020, compared to just 3 studies in the previous 40 years. Studies that focus on ballet movements, pain/discomfort and intrinsic dancer factors have been fairly consistent throughout the last 45 years. The number of studies focusing on shoe types has also increased recently, with 11 out of the 12 studies being published in the last 12 years.^{17,19,27,29,31,32,35-37,46}

Methods of included studies

The majority (86%) of the studies in this review were cross-sectional. Two of the included studies assessed in this review were case-control,^38,40 one randomized controlled trial,²⁵ one cross-over study¹¹ and one case study.⁹ Twelve studies assessed the dancers in their own pointe shoes, and the remaining 23 studies either provided new shoes (4 studies) or failed to provide data on shoe origin. Methods used for data collection differed between studies (Table 3). Of the kinematic studies, 5 studies looked at 2D data (eg, photo or video data),^{11,28,40,42,46} and nine 3D data (eg, Vicon systems).^{16,18,23,27,29-31,35,39} For kinetics, 19 studies used force plates,^{16-19,22-25,27,29-32,34,37-39,41,46} 3 pressure sensors,^26,44,45 and one used a mobile phone application.³⁶ Four studies used EMG,^18,23,33,37 5 questionnaires,^3,7-10 and 3 imaging (X-ray¹¹ and MRI^8,43).

Table 3.

Method and Findings of Included Studies.

Study	Own shoe	Aim	Outcomes	Results
Albers et al²²	NR	Compare walking barefoot and in pointe shoes, compare élève, relevé and passé en pointe change élève and relevé	Peak pressure	Increased pressure walking pointe shoe compared barefoot Increased relevé passé compared to walking No difference between élève, & relevé passé
Aquino and Amasay¹⁶	YES	Compare new pointe shoes and dead pointe shoes during relevé, sous-sus, and pirouette	Center of pressure, Sway area, Ground reaction forces	Dead shoe vs new: Increased sway area during relevé, sous-sus, and single pirouette Increased GRF AP in new shoes
Aquino et al²³	YES	Compare “dead” and “new” pointe shoes when performing relevé and arabesque	Sway area, Peak ankle moments, Muscle activity tibialis anterior & medial gastrocnemius	Dead shoes vs new: Increased tibialis anterior activity arabesque Increased sway relevé and arabesque
Bickle et al³⁰	NR	Investigate differences between new and worn pointe shoes during bourreés	Peak vertical force, Center of pressure velocity plantarflexion + mid-foot flexion	Worn shoe vs new: Increased mid-foot flexion & ankle plantarflexion
Buckner³	YES	Investigate the relationship between brand of pointe shoes and discomfort	Area of discomfort while wearing pointe shoe	Top 3 areas of discomfort were toenails, big toe, and pinky toe. Users from every brand had toenail discomfort
Chockley²⁴	NR	Compare sauté landing en pointe and landing on the full foot	Ground reaction forces	Vertical jumps landing en pointe =two distinct landing phases “shock” & “relaxation.” en pointe landing created 72.2% of the force that landing on the full foot did
Clarkson et al⁴⁰	NR	Examine and compare relevé, sauté and en pointe from demi plie	Reaction time, Depth of plie	Reaction time for sauté was faster than relevé and en pointe conditions, the depth of plie same across conditions
Cox and Herzog²⁵	NO	To determine the short-term effect of a pointe shoe toe box shape on proprioception	COP area, Reaction velocity	No main effect for toe box type
Farmer³³	YES	Examine rising to demi and then full pointe in pointe shoes	Gastroc, tib ant, peroneus longus and FDL: muscle contraction pattern Strength	Typical pattern = gastrocnemius, peroneus longus and then flexor digitorum longus. tibialis anterior variable. peroneus longus increased active en pointe movement, tibialis anterior increased activity during pointe flexor digitorum longus increased en pointe
Golomer and Chatellier⁷	NR	Investigate cutaneous pathology as a result of pointe shoes and the relationship between tightness and pathology	Skin lesions	Most frequent= mechanical keratomdermia (corns/calluses). Soft corns related to pointe shoe tightness
Hugel et al³⁴	NR	Analyze performance during bipodal en pointe eyes open/closed and unipodal en pointe eyes open only	Way (W) Area (A) Way area (W/A) ratio Sway lateral and antero posterior planes Antero-posterior/Lateral ratio Romberg quotients	Bipodal en pointe eyes open vs closed: No sig diff except decreased AP oscillations Unipodal en pointe increased ways and left foot center foot pressure area displacements
Huh³¹	NR	Investigate differences in balance performance in different ballet positions and shoe types	Base of support (BOS)	BOS smaller on tip toes in the AP direction. ML direction values are smaller in pointe shoes than ballet shoes
Kadel et al¹⁸	YES	Analyze rise to demi-pointe, pointe (elevé), piqué passé and a two-foot spring up to pointe	Ankle motion (degrees DF) Ankle moment EMG gastroc, soleus, peroneals, and tibialis anterior	Increased PF on pointe elevé, muscle activity increased during rise to pointe, and decreased once position achieved. Gastrocnemius increased for elevé pointe and demi-pointe. Soleus decreased during rise from foot-flat to demi-pointe, not pointe
Kizawa et al¹⁹	YES	Investigate postural stability according to toe length wearing soft slippers, demi-pointe and pointe shoes	Trajectory COP, Total distance of COP Displacement in AP and ML directions	No sig diff between toe type in bipedal-stance and demi-pointe. En-pointe, the LNG, VML, MAXML, and MAXAP of Egyptian-type toes were greater than square-type toes
Kravitz et al²⁶	NR	Analyze echappé,relevé and passé en pointe	Pressure on aspects of foot	Increased pressure on medial foot, especially the plantar and medial first IPJ both movements. At top movements increased pressure tip big toe
Leslie²⁷	YES	Examine landing from grand jeté in pointe shoes, ballet slippers and barefoot	Displacement Velocity, Acceleration of the ankle and knee, Peak GRF, Rate of loading, Force-time characteristics of GRF	All 3 components of the GRF and peak rate of loading vertical GRF were the highest for the pointe shoe condition
Lin et al³⁹	NR	To study relevé en pointe and investigate symmetry between dominant and nondominant sides.	Peak ROM, Peak moment, Moment range	Similar ROM and excursion patterns but different initial moment exertions and peak moments on dominant and nondominant sides, as well as sig diff peak moments (increased left ankle)
Lin et al³⁸	NR	Determine postural stability in single-leg standing, first and fifth positions, and en pointe in injured and uninjured dancers	Postural stability AP + ML Trajectory AP +ML	Injured had increased max displacement in medial-lateral and anterio-posterior direction en pointe compared to non-injured
McPherson et al¹⁷	YES	Investigate landing from assemble and grand jeté in pointe shoes, flat shoes, and barefoot; and explore the effects of specific pointe shoe characteristics	Max GRFs Mean vertical + horizontal jump height +distance	Jeté increased GRF. No sig diff between 3 shoe conditions. Distance increased in jeté and height increased in assemble. Neither shoe age nor shank style had any sig impact on GRF
Paderi et al³⁶	YES	To verify the reliability of estimating ballet dancers’ postural stability during the unshod and the en pointe relevé position with a smartphone application	Postural Stability CoM point displacement	Worse postural stability in the en pointe condition, with no significant temporal differences (time percentage of CoM displacement)
Pearson and Whitaker³²	NO (1 week to wear in)	Compare demi-pointe shoes with soft and pointe shoes. Performing demi plie to demi pointe in barefoot, soft shoe, demi pointe shoes and pointe shoes	Contact area Peak pressure, Pressure time integrals, Force	Sig diff in pressure between barefoot and pointe shoe and soft and pointe shoe conditions. Pointe shoes increased plantar surface pressure. At midfoot, the shoe conditions decreased in contact area progressively from barefoot to pointe shoes
Penitente et al⁴¹	NR	Compare novice and intermediate dancers performing echappé relevé en pointe	Temporal vertical force, Postural sway variables	No sig diff
Russell et al⁸	NO- no metal	Develop protocol for scanning en pointe and correlate pain to pathology through survey and MRI en pointe	Ant/post ankle pain	Average anterior ankle pain = 5.4, Average posterior ankle pain = 8.7
Russell et al⁴²	NR	Determine differences in demi-plié and en pointe	WB and NWB ankle range	PF range en pointe increased compared to non-weight bearing PF
Russell et al⁴³	YES	Quantify the contributions of the talocrural joint and pairs of foot bones to the extreme PF and DF movements in ballet dancers via xray	Foot + ankle ROM and Motion	In en pointe and demi-plie ́ positions, talocrural joint accounted for 70.6% and 72.3% of motion, respectively.
Salzano et al¹¹	NR	Investigate the effect of using different toe caps (custom vs standard) via MRI	Toe deviation angle (TDA) Pain	Custom cap: decreased TDA, and pain. Standard cap: increased TDA and pain
Saleh³⁵	NR	To identify the lower limb kinematic properties of, and differences between Le Petit Échappé with training pointe and professional pointe shoes	Horizontal and vertical joint (toe, heel and ankle) velocity, acceleration and displacement and ankle PF range	No differences in the kinematic variables between the 2 shoe types. Larger ankle plantarflexion range with professional pointe shoe.
Skrinar et al²⁸	YES	Examine the differences between first position flat and en pointe in Capezio, Freed or Zubiller brand shoes	Pelvic tilt	Capezio shoes increased pelvic tilt from flat to on pointe, no difference with other shoes
Teitz et al⁴⁴	NO	Determine relative toe pressures when dancing en pointe, and variation of these pressures as a function of toe length, foot position, and padding	Toe pressure Pressure ratios	Second toe pressure and pressure ratios diff from group 1 (even toe length) to group 2. In group 2 (first 3 toes decreased length), capping the 2nd toe doubled the pressure on that toe. Everted relevé = increased pressure first MTP joint
Torba et al⁴⁵	NR	Analyze the pressures in the foot of a ballet dancer wearing pointe shoes	Pressure	Pressure increased ends of toes and joints. Soft tissue flattening and overall deformation of the foot into the shape of the toebox
Tsubaki et al³⁷	YES	To clarify the differences in COP displacement and lower limb muscle activity during the descending phase of a relevé when wearing pointe shoes versus flat shoes	Postural stability COP Displacement Lower limb muscle activity	COP shifted more laterally and the Tibialis Anterior and Soleus activities increased when the subjects were wearing pointe shoes
Veirs et al²⁹	NR	Assess elite ballet dancers barefoot and en pointe in relevé action	ROM joint Segment angles	Hallux sagittal plane peak angle was sig increased ROM en pointe. Increased sagittal movement and increased rotational movement on relevé barefoot than en pointe
Wakes and Caudwell⁹	NR	To examine the pointe shoe from the dancer’s point of view in terms of injury or discomfort	Injury/discomfort	Toe discomfort and/or injury n = 7/9 occurs after prolonged use n = 6/9
Walter et al⁴⁶	NR	To determine whether the type of dance shoe used (flat or pointe) effects the assemble movement	GRF Vertical jump height	GRFmax greater for landings in flat shoes than in pointe shoes. No diff in jump height
Zepeda¹⁰	NR	Determine anthropometry, ROM, and injuries of male pointe dancers	Pain en pointe	33.1 ± 8.2 Anterior ankle pain en pointe

Abbreviations: AP, anterior-posterior; BOS, base of support; COP, center of pressure; CoM, center of movement; CTC, customized toe cap; DF, dorsiflexion; EMG, electromyographic; GRF, ground reaction force; PF, plantar flexion; LNG, length of trajectory; MAXML, maximum medial-lateral; MAXAP, maximum anterior-posterior; ML, medial-lateral; MRI, magnetic resonance imaging; NR, not reported; ROM, range of motion; STC, standard toe cap; VAS, visual analog scale; VML, velocity medial-lateral.

Outcomes

One study explored pelvic kinematics (pelvic tilt, determined by measuring the distance between markers on the patella and the anterior superior iliac spine)²⁸ and 2 joint kinematics (toe, heel, ankle and knee angular velocity, acceleration, and displacement).^27,35 Three studies explored ankle kinetics exploring ankle moment,¹⁸ peak net ankle inversion and plantarflexion moment²³ and ankle plantar flexion and dorsiflexion moment range.³⁹ Eight studies explored GRF,^{16,17,22,24,27,30,41,46} 11 postural stability (eg, sway or center of pressure trajectory),^{16,19,23,25,30,31,34,36-38,41} 8 range of motion,^{18,27,29,30,35,39,42,43} 3 foot forces (eg, in shoe pressure transducers in various locations),^26,44,45 one reaction time.⁴⁰ Those studies that did not focus on biomechanics explored symptoms,^3,7,9-11,42 muscle activity,^18,23,33,37 and function (eg, vertical/lateral jump height/distance^17,46 and depth of plié)⁴⁰ (Table 3).

Seven of the 8 studies exploring joint range outcomes reported ankle range (either/or dorsiflexion or plantar flexion or displacement range).^{18,27,29,30,39,42,43} One of the 8 studies reported knee ranges.^27,39 Three studies explored foot joint ROM variables. The first looked at midfoot flexion (calculated using 3D motion capture data and a published foot model).³⁰ The second looked at tibial-talar range, talar-navicular, navicular-cuneiform, cuneiform-metatarsal ranges (measured from Xray films).⁴³ The third examined 4 tri-planar intersegmental articulations (between the calcaneus-metatarsal, calcaneus-midfoot, metatarsal-hallux, and midfoot-metatarsal) and the medial longitudinal arch, hallux, the angle between the second and first metatarsals and second and fifth metatarsals and the angle between the shank and the calcaneus (3D motion capture data).²⁹

Ground reaction force (GRF) variables differed between studies. Four of the 8 studies that investigated GRF normalized the findings to body weight.^16,17,27,41 Three of the 8 studies reported variables in addition to max vertical GRF, with Aquino and Amasay¹⁶ also reporting peak GRF in the anterior-posterior and medio-lateral and directions, Leslie²⁷ reporting medio-lateral and braking/acceleration maximal GRF and force time characteristics and Penitente et al⁴¹ including average loading rate at impact en pointe (calculated between 20% and 80% of the time to impact peak). Postural stability outcomes were typically a measure of sway area^{16,23,25,34,41} or sway distance/trajectory/displacement in anterior-posterior and medial-lateral directions.^{19,31,34,36-38,41}

Research aims of included studies

Several studies were classified into more than one category (shoe factors, shoe types, ballet movements, symptoms, and intrinsic dancer factors) as multiple aims were reported (Figure 2).

Shoe factors

Nine of the included studies^{3,7,11,16,17,23,25,28,30} investigated pointe shoe factors (Table 3). Four studies published within the last 2 years examined the effect of shoe wear, or “new vs dead” (shoes that no longer provide adequate foot support) pointe shoes.^16,17,23,30 Dead pointe shoes appear to challenge dancer postural control,^16,23 induce greater calf muscle activation and midfoot joint active range³⁰ compared to new shoes, and resulted in lower GRF (anterior-posterior) direction during relevé (movement from bent knees rising to en pointe),²³ but do not appear to have an impact on GRF in jumping¹⁷ or bourrées (small quick steps).³⁰ The use of custom toe caps appears to reduce toe deviation angle and pain experienced,¹¹ while different toe box shapes have no impact on proprioception.²⁵ Toenail discomfort was reported regardless of shoe,³ however dancers demonstrated an increased pelvic tilt (determined by measuring the distance between markers on the patella and the anterior superior iliac spine) en pointe while wearing one brand of shoes.²⁸

Shoe types

Ten studies investigated the impact of pointe shoes compared to other shoe types (eg, flat ballet shoes, demi pointe shoes) or barefoot.^{17,22,27,29,31,32,35-37,46} Two studies used shoe type as a condition, but did not conduct statistical comparisons.^19,35 Six studies compared movements in flat ballet shoes,^{17,27,31,32,37,46} 2 in demi-pointe shoes^32,35 and 6 barefoot,^{17,22,27,29,32,36} to the same movement or an equivalent movement in pointe shoes. Five of the included studies investigated the outcome of plantar pressure or GRF.^{17,22,27,32,46} Three of these 5 studies reported a positive relationship, with GRFs higher when walking in pointe shoes compared to barefoot,²² landing a grand jeté (broad, split leap) in pointe shoes compared to soft ballet shoes and barefoot²⁷ and plantar surface pressure higher in pointe shoes compared to demi pointe shoes and soft ballet shoes when moving from demi plié to demi-pointe position.³² No GRF differences were found between pointe shoes, soft ballet shoes and barefoot conditions in landing assemblés (movement in which a dancer’s feet or legs are brought together in the air and the dancer lands on both feet) or grand jeté,¹⁷ and lower GRFs were observed when landing an assemblé in pointe shoes compared to soft ballet shoes.⁴⁶ Postural stability measured in second position of the feet was similar (anterio-posterior and medio-lateral translations in base of support) in pointe shoes and soft ballet shoes (flat and demi pointe foot positions).³¹ Whereas, the center of pressure in the forefoot shifted laterally during the descending phase of a relevé movement in pointe shoes compared to soft ballet shoes.³⁷ Postural control (total center of movement displacement and quadrants) was reduced during relevé en pointe in parallel first position compared to barefoot.³⁶ Toe, foot and ankle kinematics appeared similar (no analysis) between demi pointe and pointe shoes during la petit éshappé movement, but ankle plantarflexion range appeared larger while en pointe.³⁵ Finally, pointe shoes (compared to barefoot) increased the sagittal peak angle of the hallux during relevé en pointe in first position (heels together, toes pointed outwards to the side).²⁹

Ballet movements

Eleven of the included studies investigated how various outcomes differed between different ballet movements wearing pointe shoes.^{17,18,22,24,26,31,33,34,40,42,43} When assessing forces, rising to en pointe position from straight legs exerted no more peak GRF than walking,²² but landing a sauté (a jump from 2 feet that lands on 2 feet) by articulating the feet was more forceful than starting en pointe and landing en pointe (72% of the GRF of articulated landing).²⁴ Surprisingly, no differences between peak GRF were demonstrated between rising to en pointe position and relevé devant (a strong movement from bent knees to en pointe with one foot touching the supporting knee).²² When the pressure distribution around the foot is examined (in-shoe transducer sensors), the movement of both relevé devant and échappé relevé (a movement from a closed foot position eg, first or fifth foot position to an open position eg, second position) exerts the greatest pressure on the plantar and medial aspects of the head of the first metatarsal joint, but when en pointe, the force shifts to the distal hallux.²⁶

Muscle activity and timing appears to differ between movements. Activity of the plantarflexors and dorsiflexors increases during movements rising to an en pointe.^18,33 Specifically, tibialis anterior activity increases once en pointe,³³ and soleus is more active in movements rising to en pointe compared to demi pointe.¹⁸ As expected, en pointe plantarflexion joint ROM is greater than non-weight bearing plantarflexion⁴² and the talocrural joint contributes approximately 70% of the motion allowing a dancer to stand en pointe.⁴³

Symptoms and skin health

Five of the included studies^3,7-10 investigated symptoms and skin health, such as foot and ankle pain and discomfort, injury to the feet and cutaneous pathology resulting from wearing pointe shoes. The toes are a common area of pain whilst en pointe,^3,9 and corns and calluses were the most common skin lesion.⁷ The posterior ankle was a commonly reported area of pain for female dancers,⁸ however, the anterior ankle was more commonly reported as an area of pain in males dancing en pointe.¹⁰

Intrinsic dancer factors

Seven of the included studies^{19,34,38,39,41,44,45} examined how intrinsic dancer factors affect wearing pointe shoes. Two studies^19,44 investigated the impact of foot types and toe length on foot pressures. It appears that toes that decrease in length from the big toe increase pressures on the forefoot in pointe shoes when compared with all toes of a similar length.^19,44 It also appears that pressures on the feet when wearing pointe shoes are mostly increased at the ends of the toes.⁴⁵ Postural stability en pointe was only impacted by injury³⁸ and not level of experience⁴¹ or visual input (eyes closed).³⁴

Discussion

The purpose of this scoping review was to map the evidence and identify knowledge gaps related to the effect of wearing pointe shoes on professional, pre-professional and recreational ballet dancers. A total of 35 studies were identified for inclusion. The included studies examined a wide range of areas, including shoe factors, shoe types, ballet movements, symptoms and intrinsic dancer factors. Most studies used laboratory-based techniques to collect data (eg, 3D sensors and force plates) and reported on predominantly biomechanical outcomes. Few studies assessed dancers in their own shoes. The field of research demonstrates growth, with an increase in studies in the last 15 or so years.

Reflecting anecdotal evidence, the studies with a focus on skin health and symptoms suggest that wearing pointe shoes can cause pain and discomfort^3,8-10 and skin issues.⁷ Two studies suggest factors related to customization and correct fitting may contribute, with tightness related to soft corns⁷ and custom toe caps reducing pain.¹¹ Corn and callous formation are the skin’s protective response to extreme or sustained pressure or friction.⁴⁷ Both intrinsic (eg, bony prominences, foot biomechanics such as hallux valgus and skin disorders such as tinea and friction blisters) and extrinsic factors (eg, poorly padded or fitted shoes and overtraining/overloading) can contribute to corn formation.⁴⁷ Pointe shoe box tightness, an extrinsic factor, would theoretically compress the toes together and potentially misalign them, leading to increased friction on not just the outer aspects of the first and fifth toes, but also between the toes. Anecdotally, toe spacers are used to manage or prevent foot discomfort while en pointe. The use of fabric or silicon toe caps to cushion the toes inside the shoe box, are also anecdotally used by all levels of ballet dancers to reduce pain and discomfort en pointe. Custom made toes caps, molded to individual dancers’ toe shapes, may result in less pain than off the shelf toe caps by reducing the pressure at the toe tips (as reported by Torba and Rice⁴⁵ in this review). The same study reported soft tissue flattening and deformation of dancers’ feet into the shape of the toe box while en pointe. It is plausible that custom-made toe caps could reduce the deformation and this is supported in part by the finding of smaller first toe deviation angle in custom caps compared to off the shelf versions.¹¹ Based on the basic synthesis of these studies, it is possible that professional fitting and the use of custom toe caps could mitigate intrinsic and extrinsic risk factors of corn development and reduce pain and discomfort. There have also been recent advances in pointe shoe design including use of flexible polymers for the shank and toe box and the inclusion of foam, in an attempt to enhance comfort, performance and longevity,⁴⁸ yet no data on their effectiveness has been published.

Whilst development and exploration of footwear has been a large focus in the literature amongst other sports, there is a paucity of evidence coupled with minimal attempts to synthesize information regarding pointe shoes to inform shoe-based advice. Many systematic reviews have examined the impact of footwear on athletes in various sports. Two studies reported injury risk linked to football shoe factors.^6,49 Shoe factors have been linked to functional performance (eg, ability to cut, jump and sprint) in both football and basketball.^49,50 These findings have the potential to inform shoe evolution, optimize biomechanics and performance and help prevent injuries in the sports of football, basketball, and American football.^6,49,50 Unlike the sporting literature, few functional performance outcomes have been investigated in relation to pointe shoe factors, with the focus primarily on biomechanical and symptom variables. The only functional outcomes investigated by studies in this review were jump height^17,46 and depth of plié,⁴⁰ and these studies all investigated the difference between shoe types (eg, pointe shoe, ballet flat shoe or barefoot).

To enhance the practical utility of biomechanical and symptom-based pointe shoe research, the causative relationships with performance and injury risk need to be rigorously investigated, as these are 2 outcomes of great importance to dancers. In both sport and dance, biomechanical factors such as GRF have been associated with injury, but there remains a paucity of evidence to support a causative relationship with injury, as few prospective studies exist.^51-54 Unlike sport, identification of appropriate pointe-shoe related performance outcomes is more challenging. Simple functional outcomes such as plié depth (also used by fitters to determine if the shoe is the correct length) and jump height are appropriate as they are simple components of more complex dance movements and are required for dance performance, but do not capture the complex movement patterns and unique esthetic qualities important in dance (eg, the line and shape of the foot in the pointe shoe) nor the overall performance ability of the dancer while dancing en pointe. Dance performance quality tools have been developed,^55,56 but their sensitivity to detect the effects of pointe-shoe-related factors is unknown. A recent systematic review conducted by several authors of this article located 15 dance performance outcome measures, but none assess dancers en pointe or consider the ability to dance en pointe.⁵⁷ A measure of pointe technique (ie, the ability to maintain a desired position en pointe) has also not been investigated in any of the studies in this scoping review. It is plausible that poor pointe technique would be related to poor biomechanics and possible symptoms. A pointe technique outcome measure does not exist and may be useful particularly when assessing dancers who have recently commenced pointe work. Appropriate pointe shoe-related performance variables, based on pointe technique, the desirable pointe shoe esthetics and evaluation of ballet sequences en pointe may need to be developed in conjunction with dancers and ballet teachers to enable the research to meaningfully inform pointe shoe design.

The pointe shoe exposure conditions (eg, duration in the pointe shoe and testing environment) and data collection conditions (eg, laboratory or field-based) employed by most of the studies did not accurately replicate class or performance conditions, and therefore the real-life effect of pointe shoes on the dancer. Only one study examined the effect of pointe shoes on dancers for longer than one single testing session, testing dancers before and after a 6-week exposure period.²⁵ Cox and Herzog²⁵ assigned dancers to either a square or tapered toe box, and the dancers were required to train exclusively in the assigned shoe for the 6-week study duration. Many studies employed laboratory-based data collection techniques, which although are likely to be highly reliable and valid (eg, force plate and EMG), due to the “unnatural” environment, may affect dancers’ normal movement patterns. Researchers need to consider innovative, highly valid and reliable laboratory testing methods that can be employed in a class or performance environment, such as motion capture systems to measure GRF without the need for movement restrictive force plates and wireless in-shoe pressure measurement systems.⁵⁸

Another threat to the ecological validity of studies in this review is the provision of new pointe shoes, rather than the use of dancers’ own shoes for data collection. Pointe shoes do not come “ready to wear,” and dancers often have rituals to break in their shoes, sewing ribbons and elastic to suit their ankle shape.^2,33 For this reason, providing a dancer with shoes that are not their own may not be an accurate representation of how pointe shoes are effecting dancers, and it does not mimic the classroom or stage environment. No studies have compared findings between provided shoes and dancers’ own shoes, thus the impact of this non-ecological method remains unknown. Shoe age (eg, hours used), brand and treatment of the shoes (eg, darning, elastics, ribbons, breaking in procedures, padding) will differ considerably between dancers, and as such, researchers should collect data to capture these potential moderator variables. Most of the studies that allowed dancers to use their own shoes did collect at least one of these variables and were descriptively reported and used as the independent variable (eg, comparison between shoe brands) but not explored for their moderating effects. No studies indicated whether shoes were custom-made, as is often the case for professional ballet dancers from major companies. As such, there remains a significant knowledge gap regarding the effect of pointe shoe age and shoe treatment practices.

Some studies investigated the impact of “dead” or worn pointe shoes. Dancers use a combination of triggers to decide when shoes are ready for retirement, including comfort and perceived amount of support.³ The findings of this study appear to support dancer perceptions, with dead pointe shoes challenging postural control more, suggesting less support and stability provided by the shoe, and greater midfoot flexion and ankle plantarflexion range of movement. It is plausible, the combination of poorer postural control and greater joint range in “dead” pointe shoes may increase injury risk^59-61 The definitions of “dead” were inconsistent, ranging from an average of 20 hours use to 115 hours.³⁰ All future pointe shoe studies should consider age (or hours of usage) of the shoes prior to testing to enable assessment of optimal duration of wear for all outcome types (eg, performance, injury etc.).

Based on this scoping review, the field of research investigating the effect of pointe shoes on ballet dancers is represented by 35 studies. These 35 studies are heterogeneous, with varying research aims, outcomes and methods. The 5 research aim categories (shoe factors, shoe types, ballet movements, symptoms and intrinsic dancer factors) and outcome categories (biomechanics, symptoms, muscle activity and function) can be cross-referenced to explore studies that would be considered more homogeneous; the process resulting in 1 to 11 studies and 4 to 151 participants per category. For example, 7 studies investigated the effect of shoe factors on biomechanics, with a total of 137 participants. Even at this level, heterogeneity still makes conclusion difficult, with multiple possible shoe factor and biomechanical variable options. Multiple, rigorous, homogeneous studies for each research question type are required to improve the volume and quality of evidence and allow confident translation of findings.⁶²

The search strategy used in this scoping review was comprehensive. The addition of published theses and abstracts allowed research that may not develop to a published peer-reviewed article to be included. As scoping reviews aim to map and explore a field of research, quality assessment of studies is not a requirement. As such, any inferences from the findings of individual studies in this scoping review should be considered with caution, as confidence in the quality of the evidence is low (small study/participant numbers and no quality assessment). The limitations of the present study include English publication bias and some studies were unable to be sourced. Future studies should (1) include articles written in all languages and translate findings, and (2) contact authors where articles are unable to be sourced via university library retrieval services and electronic databases. Unlike systematic reviews, scoping reviews are not used to provide clinical guidance.⁶³ As more, rigorous studies are published investigating the effect of pointe shoes on dancers, focused research questions and systematic reviews (including meta-analyses) can be conducted, and results translated to guidance for shoe developers, dancers, teachers, and parents.

Practical and Clinical Applications and Implications

This scoping review mapped the field of research regarding the effect of pointe shoes on ballet dancers and has identified an insufficient volume of evidence regarding focused research aims, significant gaps in the knowledge and threats to ecological validity. These findings should be used by researchers to advance the field of research and generate quality evidence to inform shoe design and pointe shoe practice.

Overall, there is a paucity of studies that would be considered sufficiently homogenous addressing specific research aims. If an attempt was made to utilize the current studies to inform design or practice, the low number/participants for each research question suggests imprecision and uncertainty in the results, leading to downgrading of the quality of evidence.⁶² Future studies should attempt to recruit adequate sample sizes, and researchers are encouraged to replicate existing studies to increase the quality and confidence in the evidence. Commercial pointe shoe companies that adjust their shoes with the aim of improving comfort, longevity or performance should share the research data (if any) with the wider scientific community to assist with boosting the volume of evidence.

The significant gaps in the knowledge base that are yet to be adequately explored include: functional and performance-based outcomes; injury outcomes including exploration of factors such as shoe age/usage; and pointe shoe treatment factors. Interestingly, many of the research questions yet to be explored would be considered by dancers as relevant and important for example, How does shoe age increase my injury risk? Given this, it is recommended that researchers consult and co-design pointe shoe studies with dancers and prioritize studies accordingly.

Ecological validity is essential to ensure the findings of future studies can be generalized to the real-life setting of ballet dancers taking class and performing. Shoe exposure time (ie, how long the dancer wears the pointe shoes in experiments) and testing environment should be considered to mimic the demands and natural environment of the dancers. Dancers should be assessed in their own pointe shoes, and factors such as shoe age and treatment practices collected and assessed.

Conclusion

The pointe shoe is a unique and essential component to the esthetics and optimal performance of ballet. The direct effect of pointe shoes on ballet dancers is a slowly developing area of research, with a welcome spike in interest in the last 15 years. While the investigation of shoe factors in sports is a large focus area in the literature, little research attention has been given toward pointe shoe design. Future studies should target the identified knowledge gaps and employ rigorous, ecologically valid study designs and ensure that findings inform shoe design and dancer education to minimize injury and maximize comfort and performance.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Katia Ferrar

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