The incidence of hip bone dysplasia was 54% ,showing the thinness of ischium and pubis branches, the upward lifting of ischium and pubis branches, the unregular change of arcuate line and the decreasing of iliac crest height.

• 髋骨发育不良发生率为54%25,耻坐支细小、耻坐弓底缘上提、弓状线不规则改变、髂嵴高度下移。