Abstract:

Objective To compare the short-term clinical outcomes and bone mineral density (BMD) around acetabular component between total hip arthroplasty with trabecular metal (TM) and that with Titanium alloy metal (Ti), and investigate the influence of TM acetabular component on BMD around acetabular component after total hip arthroplasty. Methods Fifteen patients undergoing total hip arthroplasty with TM (TM group) and 13 patients undergoing total hip arthroplasty with Ti (Ti group) were followed up. Harris hip scores after operation were compared between groups. Hodgkinson grading was performed according to the findings of X-ray plain film.  BMD around acetabular component was determined by dual energy X-ray absorptiometer (DEXA) based on the regions of interest (ROI) Ⅰ,Ⅱ and Ⅲ. Results There was no significant difference in the Harris hip scores after operation between two groups (P＞0.05). Hodgkinson grade 0 was identified in all patients, and there was no component loose or displacement after operation. DEXA measurement indicated that BMD values in all ROI around acetabular component of the operational side were significantly lower than those of the nonoperational side in Ti group (P＜0.05）, while there was no significant difference between BMD values in all ROI around acetabular component of the operational side and those of the nonoperational side in TM group (P＞0.05). The difference between BMD values in ROI Ⅰand ROI Ⅱ before operation and those after operation in TM group was significantly different from that in Ti group (P＜0.05）, while the difference between BMD value in ROI Ⅲ before operation and that after operation in TM group was not significantly different from that in Ti group (P＞0.05). Conclusion TM acetabular component has favorable influence on BMD around acetabular component after total hip arthroplasty.

Key words: trabecular metal, total hip arthroplasty, bone loss, bone mineral density