Estimation of Femoral Head Bone Mineral Density in Hip Fractures of the Elderly
Abstract
Objective: It is usually challenging to decide which hip fractures should be fixed and which should be replaced to avoid fixation failure and revision. Therefore, it may be of benefit to evaluate the bone mineral density of the fixation point of the femoral head preoperatively. In this study we tried to investigate the relationship between the bone mineral density (BMD) of the fixation point of femoral head, which is the primary compressive trabeculation area, and other parts of the proximal femur evaluated routinely during Dual-Energy X-ray absorptiometry (DXA) measurements.
Methods: Retrieved femoral heads of 29 patients during hemiarthroplasty for hip fracture were evaluated using DXA. These results were correlated with the DXA measurements of proximal femora of uninvolved hips of patients.
Results: Mean BMD values of retrieved femoral head primary compressive trabecular region (PC-BMD) values were 0.610 ± 11 (g/cm²). Although there were significant positive correlation of PC-BMD with neck, Ward's and total proximal femoral region as expected, highest correlation coefficient was calculated at femoral neck region. These results did not differ when patients were regrouped according to uninvolved side BMD values as osteoporotic and osteopenic. There were no difference in both sexes in this relationship between values of PC-BMD, neck BMD, Ward’s BMD and total BMD.
Conclusion: As expected, a positive relationship was found between PC-BMD values and neck BMD, ward’s BMD and total BMD values with neck BMD revealing the highest correlation. Preoperative bone mineral densitometric evaluation of the uninvolved hip, especially the neck region seems to be helpful to evaluate the densitometric status of femoral head to predict early failure when fixation was attempted.
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