Abstract: Objective:To improve the understanding of CT appearance of herniation pits of the femoral neck.Methods:The CT characteristics of 125 patients of herniation pits of the femoral neck were retrospectively analyzed.Results:During the 125 patients,lesions were only located in right femoral necks in 51 cases.33 cases of lesions only involved left femoral necks and 41 cases bilateral femoral necks were involved.218 lesions were determined during the 125 patients,including 72 solitary cases and 53 multiple cases.During the 218 lesions,121 were located in the right femoral necks and 97 in left.Lesions about 98% were located in the anterior lateral quadrant of base of femoral head and the near-end of femoral neck.The most of lesions were round or oval and all lesions were surrounded by thin clear sclerotic rims.39.4% of the lesions had crack-like cortical bone defects.The greatest diameter of the lesions was in the range of 0.3 cm to 3.0 cm.83.9% of the lesions were less than 10 mm in greatest diameter and 16.1% bigger than 10mm.CT appearance of the lesion showed that the soft-tissue density,fluid density and fat density were 17.9%,10.5% and 17.9% separately.During 6 months to 4 years follow-up study,it was found that most of the lesions without changes except that a little lesions increased in volume.Conclusions:Herniation pits of the femoral neck can be easier diagnosed by the multilayer spiral CT than by X-ray film.