Aseptic necrosis of femoral head is a familiar disease of orthopaedics. There are many causes of this disease, such as: fracture of femoral head, overload of hip joint, disorder of lipo-metabolism, ethanol poisoning, usage of steroid hormone for prolonged periods of time, and etc. However, the pathogenesis is not clear. There has been much research on ischemia due to either mechanical obstruction of the blood transportation or of degeneration the vessels themselves. The research on the amount of vessels in the femoral head, blood viscosity, speed of the blood stream, and etc have been reported. WangGj has found that blood flow in the necrotic femoral head of rabbit is obviously decreased.

        Wang has found by perfusion with ink that vessels in the necrotic femoral head were not plentiful, the capillaries were not filled well, the amount of capillaries decreased, erythrocyte aggregation, and the blood flow decreased. Xiang liang Geng San has found that different distributions of vessels produced different levels of lesions. When the vessels in the femoral head were distributed symmetrically, the osseous tissue was normal. When vessels distributed in the lateral portion of the femoral head, ossified retardation of the bone end and the presence of the necrosis were obvious; and when the vessels were distributed in the extreme lateral portion of the femoral head, many had disappeared and total vessels were rare. There was no ossification or repair of necrosis and, at that time, the femoral head was necrotic.

        So he thought that vessels had an effect on the repair of femoral head necrosis and the necrosis of femoral head was caused by the break of lateral vessels. Some scholars have found that the arterioles of the necrotic femoral head were also necrotic and hemorrhagic. Xi Ta Jin has found that the arterioles in much of the tissue of patients who got necrosis of femoral head, had breakages in the tunica media and multiple hemorrhages. However, large areas of hemorrhage and necrosis only could be seen in the femoral head. The structure of the femoral head itself determined the level of breakage in the vascular wall and frequency of hemorrhage.

        Many people have studied the pathogenesis of abnormal distribution of vessels and destruction of osteocytes in disorders of fat metabolism, specialities of fat, and fat embolism. Chuan Jin He Fu considered that necrosis of femoral head was related to disorders of fat metabolism, and the obstruction of the blood stream could be the result of fat embolism in the nutrient vessels, hypertrophy of adipocytes, and fatty degeneration in osteocytes. Qing Shui Fu Nan and Gao Gang Bang Fu have observed the femoral heads of the cadavers of individuals who had used steroids for a prolonged period of time. They found that there was an increased amount of fat in the bone lacunae under cartilage, and the fat pressed against the osteocytes. Other scholars have found that adipose tissue became increased in the medullary cavity under cartilage, the diameter of the adipocytes increased to press venules, there were fat embolisms in vessels, and there were fat drops in the osteocytes.

        The emphasis of the experimental research was to discover whether the relative indexes of femoral head necrosis would be improved after the usage of the traditional Chinese medicine―Chengzai pill. Because quite a few cases of femoral head necrosis onsets are related to osteoporosis, if the drug has good effects on osteoporosis, then we can judge the effects to the femoral head necrosis would also be better. Therefore,  we made the models of both aseptic necrosis and osteoporosis. From the results of the experiments, we concluded that Chengzai pill can increase osseous density, ossous intensity, and rigidity of rats with osteoporosis, and alleviate the condition of low estrogen. In addition, the results also support the fact that the condition of femoral head necrosis is improved.

        During the research we saw the fat drops in the lacunae and osteocytes obviously deceased, and the vascular condition was restored. From the distribution of capillaries we could see indirectly that capillaries of normal rats and administrative rats extended to substrate under the cartilage, the capillaries’ distribution was fan-shaped, and transverse branches connected the distribution. So it showed that the bone trabecula changed accordingly.

        The level of 25(OH) D3 had no obvious differences among these groups. The reason may be :

1. Alpha-D3 belongs to 1,25-2(OH)VitD3, so the level of 25(OH)D3 may not reflect the level of 1,25-2(OH)VitD3.

2. We have studied the level of 25(OH)D₃ on emasculated animals for many trials. However, the change of 25(OH)D₃ has not been reflected throughout. So it is worthy of discussing whether metabolism of VitD₃ participates in the promotion of bone growth brought by “Chengzai pill”. As for the level of 25(OH)D₃ of “Chengzai pill” group, it is low instead. Repeated experiments should be made.

        Summarily, Chengzai pill can promote the growth of bone, reinforce the intensity,density,and rigidity, increase bone weight, clear out the fat drops in bone lacunae, improve the microcirculation of bone, and improve the condition of low estrogen. Finally, it has definite effects on treating aseptic necrosis of femoral head.