Evaluation of the tibial cortical thickness accuracy in osteoporosis diagnosis in comparison with dual energy X-ray absorptiometry

BACKGROUND: Unlike public awareness around the world, osteoporosis is still underdiagnosed in most cases till bone fractures. Currently, the dual-energy X-ray absorptiometry (DEXA) is the gold standard diagnostic method of osteoporosis, but unfortunately this method is not available in all diagnostic centers, especially in developing countries. AIMS: To evaluate the accuracy of tibial cortical thickness in the diagnosis of osteoporosis compared with DEXA. MATERIALS AND METHODS: In this descriptive--analytic study, patients suspicious of osteoporosis who referred to Imam Khomeini Hospital, Ahvaz from 2016 --2017 were recruited. Data was collected for each patient including age, sex, radiography, and DEXA. The total thickness of the tibia cortex (sum of the two sides) was measured using knee anteroposterior radiography at 10 cm from the proximal tibial joint. The bone mineral density (BMD) was measured by DEXA method and reported as T-score. RESULTS: In this study, 62 patients (90% female) were evaluated. The mean age of the patients was 57 years (range 45--80 years). T-score had a direct significant correlation with TCT level (r = 0.51, P < 0.0001). Also, T-score had a reverse and significant correlation with age of patients (r = −0.280, P = 0.028). The area under the curve (AUC) was 77%. Also, the sensitivity and specificity for the TCT level less than 4.37 mm (as cutoff point) was 100% and 39.1%, respectively. CONCLUSION: The findings of this study indicate that TCT has a direct significant correlation with the T-score obtained by the DEXA method. It has also been shown that TCT can be a relatively accurate diagnostic tool for predicting osteoporosis.