To analyze short-term effects of hip abduction exercise on Graf type IIa hip joint in infants.

A total of 78 infants born at Haiyan County Maternal and Child Health Hospital from January 2017 to June 2017 were diagnosed with Graf type II a hip joints (90 hips) by ultrasound using the static Graf method. They were selected and randomly divided into either an intervention group (n=41, 47 hips) or a control group (n=37, 43 hips). The intervention group was treated by hip abduction exercise, while the control group did not. After 1~2 months, ultrasound examination was performed to compare the improvement of the α angle in the two groups. The Student′s t-test was used for comparing the age at initial examination, age at reexamination, interval of reexamination, initial α angle, α angle at reexamination, and the improvement of the α angle between the intervention group and the control group. The χ² test was used to compare the sex ratio of the infants between the two groups.

The α angle increased in both the intervention group and control group (t=12.71 and 13.63, respectively, P<0.001), and the improvement of α angle in the intervention group was more significant than that in the control group (t=2.219, P=0.029). There were no significant differences in the gender ratio, age at initial examination, age at reexamination, or interval of reexamination between the two groups (P>0.05).

Compared with the natural outcome, hip abduction exercise can promote Graf IIa hip joint maturity in the short term.