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

Abstract

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

Sagittal Integral Morphotype of Competitive Amateur Athletes and Its Potential Relation with Recurrent Low Back Pain

“…In addition, LBP history was more frequent in female CAA for all except for hypolordosis. Similar to previous studies [6,10,15,27], most of the CAA studied showed normal SIM and no LBP history.…”

“…In this study, female CAA also showed structured hyperlordosis with higher frequency values than those previously reported in inline hockey players [10] and dressage riders [6]. The hyperlordosis in the relaxed standing position and slump sitting position and hypokyphosis in the maximum trunk forward flexion position show that the 21.21% of female CAA had structural hyperlordosis in the lumbar spine, which can cause joint tissue injury and resulting pain [25,27,64]. In male CAA, the most frequent type of lumbar SIM misalignment was the static functional lumbar hyperkyphosis, with a frequency significantly lower to those found in inline hockey players [10] and equestrian riders [6].…”

“…However, CAA with hyperlordosis and static functional lumbar spine characterized by misalignment in the relaxed standing position and slump sitting position, respectively, had a higher incidence of LBP than CAA with structured hyperlordosis and hypolordosis. Spinal positions maintained in the usual postures adopted during sports [18,19,27] and daily activities [65] have been shown to be an important risk factor for LBP. In addition, LBP history was more frequent in female CAA for all except for hypolordosis.…”

“…The sagittal thoracic and lumbar curvatures of the CAA were assessed in the relaxed standing position, slump sitting position, and maximum trunk forward flexion position according to the previously described procedure [27,40]. The SIM was determined by combining the sagittal spine morphotype in the three positions (Figure 1) mentioned above (relaxed standing, slump sitting, and maximum trunk forward flexion) [27,40]. Thoracic and lumbar curvatures were measured using an ISOMED Unilevel inclinometer (ISOMED, Inc, Portland, Oregon).…”

“…Thoracic and lumbar curvatures were measured using an ISOMED Unilevel inclinometer (ISOMED, Inc, Portland, Oregon). Negative values represent the degree of posterior concavity or lordosis, and positive values represent anterior concavity or kyphosis [27].…”