Lower-Extremity Alignment Asymmetry Between Supporting and Gesturing Legs in Ballet Dancers

Introduction: In this study, we compared lower-extremity alignment between the supporting leg (SL) and gesturing leg (GL) in ballet dancers and examined whether alignment asymmetry varies according to SL dominance. Methods: Twenty-two female ballet dancers (mean ± SD age, 21.55 ± 1.82 years; ballet experience, 15.00 ± 2.45 years) with no history of lower-extremity injury participated in this cross-sectional study. Based on habitual SL use during ballet-specific movements (passé and en dehors), assessed using a structured questionnaire, the participants were classified as SL-left (SLL; n = 14) or SL-right (SLR; n = 8). Static lower-extremity alignment variables were measured bilaterally under weight-bearing (WB) and non-weight-bearing (NWB) conditions in the supine, prone, and standing positions. SL-GL differences were tested using Wilcoxon signed-rank tests, and SLR differences in asymmetry indices were tested using Mann-Whitney U tests. Results: Under NWB conditions, the SL exhibited more inverted rearfoot alignment than the GL ( P = .028, r = .47). Under WB conditions, the navicular drop was greater in the GL than in the SL ( P = .015, r = .52). No statistically significant SL-GL differences were observed in proximal alignment variables. In the dominance comparison, the SLR group demonstrated greater asymmetry in Q-angle ( P = .040, r = .44) and rearfoot alignment ( P = .037, r = .45) under NWB conditions, whereas proximal alignment asymmetry did not differ between the groups. Conclusion: In this sample of female ballet dancers, lower-extremity alignment asymmetry was most evident in the distal segments and varied according to limb role and loading condition. SL dominance was associated with the magnitude of distal asymmetry, particularly in foot and rearfoot alignment variables. These findings suggest that distal alignment asymmetry in ballet dancers may represent role- and load-dependent functional adaptations, highlighting the importance of limb-specific assessment under both WB and NWB conditions.