How does ballet alter ankle tendinous morphology and hemodynamics in asymptomatic dancers? An ultrasonographic study

Introduction/Background Among symptomatic dancers, sonographic abnormalities are common. Whether asymptomatic dancers have any abnormalities remains unknown. Some dancers became cyanosis over distal feet after ballet training. The hemodynamic changes at the feet in ballet are not clearly understood. We aimed to investigate tendon morphology and hemodynamic changes in ankles of asymptomatic pre-professional ballet dancers with ultrasonography (US). Material and method In 25 dancers and 14 non-dancers, B-mode US was used to measure cross-sectional areas (CSA) of flexor tendons in the ankle. Doppler US was used to measure peak velocity of posterior tibial artery in three ankle postures: the neutral position, passively and forced actively plantar flexion (en pointe). The big toe oxygen saturation was recorded in neutral position and during 1-minute en pointe. Nonparametric Mann–Whitney test was used for between-group comparison and Wilcoxon signed-rank test for within-group comparison. Results Ankle plantar flexion range of motion was significantly larger in dancers ( P 2 [0.2, 0.3] vs. 0.21 cm 2 [0.17, 0.24], P P  > 0.05). The peak velocity was significantly higher in passively plantar flexion than in neutral position ( P P P Conclusion US showed the FHL tendon thickening and en pointe-related vascular compromise in pre-professional dancers, even when they were asymptomatic.