RESUMEN
Objective To observe the effect of ultrashort wave diathermy on collagen type I expression in early stage of hormon-induced avascular necrosis of the femoral head (ANFH) in rabbit.Methods A total of 40 New Zealand white rabbits were randomly divided into two groups:a control group (n=10) and a treatment group (n =30).All the animals in the treatment group were injected with horse serum and methylprednisolone to establish the ANFH model,and then divided into 2 subgroups:a model group and a ultrashort wave diathermy group,which were treated accordingly.After 12 weeks of treatment,all the animals were sacrificed and collagen type I expression in the femoral head was observed.Results It was shown that the expression of the collagen type I was significantly lower in the model animals than that in the controls as indicated by the stronger immunohistochemistry staining for rabbit collagen type,while that of the ultrashort wave diathermy group was significant higher than the control group ( P