PURPOSE: Algorithms to get cross-sectional bone density pattern(transverse histogram) to predict the loosening of hip prosthesis using DXA(Dual X-ray Absorptiometry) have been developed. We performed this study to analyze the correlation between radiologic findings and densitometric pattern of the THRA(Total Hip Replacement Arthroplasty) patients. MATERIALS AND METHODS: Thirty-six hips of 32 THRA patients were evaluated. The duration between THRA and DXA was from 1 year 7 months to 15 years. On transverse histogram, the periprosthetic bone density patterns were classified as 3 types;type I, rigid fixation in 17, type II, definite loosening in 8, and type III, partial loosening in 11 cases. Surgical findings, plain X-ray findnings and transverse histogram using DXA were correlated. RESULTS: Among 14 cases performing revision for acetabular prosthesis loosening, 5 cases revealed loosening of fernoral stems while 9 cases revealed rigid fixation of femoral stems. Sensitivity was 100% for either plain X-ray or DXA. Specificity was 88%, 77% for plain X-ray and DXA respectively. CONCLUSION: This preliminary study reveals that periprosthetic bone density pattern on transverse histogram on DXA may be useful in the evaluation of the loosening. However, further study will be needed for clinical application.