Kinematic Evaluation of the Classical Ballet Step “Plié”

Abstract

Lack of alignment between the lowerlimb structures, such as the hips, knees, and longitudinal arches of the feet, has been described as an important predisposing factor in musculoskeletal injury among classical ballet dancers. However, no studies were found that analyzed basic ballet movements with quantification of objective criteria of the movements. The purposes of this study were: 1. to establish a methodology to quantify, using kinematic evaluation, the technical criteria that guide the correct execution of all phases of the plié (simultaneous flexion of the hips, knees, and ankle joints); and 2. to explore whether experienced ballet dancers respect those criteria when performing the plié. The technical criteria considered were the following: 1. midfoot stability; 2. pelvic positioning in a neutral alignment; 3. pelvic stability, represented by pelvic angle variation; and 4. vertical alignment of the knee joint with the second toe of the ipsilateral foot. Twenty dancers from Porto Alegre, Brazil, with 18 years of uninterrupted ballet training, were filmed while performing plié using four synchronized cameras. The descriptive statistical analysis involved calculating the median, minimum, and maximum of each of the technical criteria. Results showed that for criterion 1, the 20 dancers showed great stabilization of the midfoot; for criteria 2 and 3, 18 dancers displayed pelvic instability tending toward retroversion throughout execution of the plié; and for criterion 4, 13 dancers presented with medial misalignment of the knees at all phases of the plié. Using these criteria, it was possible to characterize the plié from a kinematic point of view.

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

“…Although, this strong static musculoskeletal control may not necessarily extend to quick dynamic dance movements. According to Gontijo et al [43] arch height stability classification, some of the dancers who demonstrated ‘excellent stability’ in both static first positions experienced dynamic ‘instability’ during sautés landings. These dancers demonstrating increased dynamic arch ‘instability’, and therefore, potentially are exposing the posterior tibial muscle to excessive eccentric forces and tensile loads [47].…”

“…Navicular height in relation to the laboratory coordinate system (in millimetres) was analysed with the variation in height from the natural double leg up-right posture indicating navicular drop. Navicular drop was classified into three types of arch height stability according to Gontijo et al [43]: 1. ‘excellent stabilisation’ navicular drop < 7 mm); 2.…”

Dynamic Neuro-Cognitive Imagery (DNITM) Improves Developpé Performance, Kinematics, and Mental Imagery Ability in University-Level Dance Students

“…Increasing hip joint ROM is especially challenging and may result in loading the sacroiliac joint and lumbar spine (DeMann, 1997; Bronner and Ojofeitimi, 2011) if not done correctly (DeMann, 1997; Deckert et al, 2007; Gontijo et al, 2015). The developpé is a core ballet movement consisting of lifting the leg, performed routinely by dance students of all ages and levels of expertise.…”

“…Dynamic pelvic alignment (Franklin, 2012, 2014; Gontijo et al, 2015) and pelvic control (Gildea et al, 2015) are other important components for developpé performance (Holt et al, 2011), serving as a key element for whole-body axial postural alignment (Keller and West, 1995; DeMann, 1997; Wilson et al, 2004; Gontijo et al, 2015) and for facilitating efficient movement at the hip joint (Deckert et al, 2007). Correct pelvic dynamic alignment synchronized with the hip motion (known as “pelvi-femoral rhythm” (Bohannon et al, 1985; Murray et al, 2002) contributes to full hip ROM and efficient lower extremity motion (DeMann, 1997), especially in extreme positions such as developpé (Norkin and Levangie, 1992).…”

“…Improper pelvic alignment (e.g., excessive pelvic tilt), on the other hand, is undesired in dance and is a sign of lack of pelvic control (Deckert et al, 2007) that can increase the risk for injuries (Deckert et al, 2007; Gontijo et al, 2015). For example, excessive pelvic posterior tilt may serve as a compensation for insufficient hip ROM (Watelain et al, 2001) and may facilitate “tucking under” of the pelvis, thus over-loading the low back (Hagins, 2011) and impacting the dancer’s upright posture (Hanrahan, 1995; Franklin, 2014).…”