ObjectiveTo compare the effect of three kinds of intrinsic foot muscle exercise on flatfoot. MethodsFrom September to November, 2022, 45 subjects with flatfoot from Capital University of Physical Education and Sports were randomly divided into short foot exercise (SFE) group (n = 15), toe-spread-out exercise (TSOE) group (n = 15) and short foot & toe-spread-out exercise (SF+TSOE) group (n = 15), who received SFE, TSOE and SF+TSOE, respectively, for eight weeks. The cross-sectional area of abductor hallucis muscle, navicular drop test (NDT) and Chippaux-Smirak index (CSI) were measured before treatment, four weeks after treatment and eight weeks after treatment. ResultsThree subjects dropped out in each group. The main effect of time was significant for left and right cross-sectional area of abductor hallucis muscle, NDT and CSI (F > 13.906, P < 0.001). The main effect of group was not significant for left and right cross-sectional area of abductor hallucis muscle, NDT and CSI (F < 1.934, P > 0.05). The interaction effect of group and time was significant for left and right NDT (F > 3.044，P < 0.05), and it was better in SF+TSOE group than in SFE group and TSOE group (P < 0.05). ConclusionSF and TSOE can improve the cross-sectional area of abductor hallucis muscle and foot morphology in subjects with flatfoot, and the combination of them may be more effective.

ObjectiveTo compare the effect of toe-spread-out exercises (TSO) and modified TSO in females with hallux valgus. MethodsFrom September to December, 2023, a total of 45 females with hallux valgus were recruited in Capital University of Physical Education and Sports and randomly divided into blank control group (n = 15), TSO group (n = 15), and modified TSO group (n = 15). The blank control group received no intervention, the TSO group received routine TSO, and the modified TSO group received fibularis longus fascia release followed by TSO, for eight weeks. Changes in the hallux valgus angle (HVA) and the cross-sectional area (CSA) of the abductor hallucis muscle were measured before intervention, and four and eight weeks after intervention, respectively. ResultsOne case dropped out from the blank control group. The changes of HVA in the TSO and modified TSO groups were significantly greater than in the blank control group (F > 15.263, P < 0.05). After four weeks of intervention, the change of left HVA in the modified TSO group was significantly greater than in the TSO group (P < 0.05). The main effect of time was significant on the CSA of the abductor hallucis muscle (F > 13.245, P < 0.05). The main effect of group was significant on the left foot's CSA of the abductor hallucis (F = 3.798, P < 0.05). The interaction effect of time and group was also significant (F > 4.744, P < 0.05). The CSA of the abductor hallucis in both the TSO and modified TSO groups after four weeks and eight weeks of intervention was significantly greater than before intervention (P < 0.05). At eight weeks, the CSA of the right foot in the modified TSO group was significantly greater than in the blank control group (P < 0.05). ConclusionBoth TSO and modified TSO can improve HVA and the CSA of the abductor hallucis muscle in females with hallux valgus, and modified TSO is better.