Markel M D, Gottsauner-Wolf F, Bogdanske J J, Wahner H W, Chao E Y
Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison 53706.
J Orthop Res. 1993 May;11(3):452-6. doi: 10.1002/jor.1100110319.
The effect of a press-fit and cemented titanium alloy endoprosthesis on the measurement of bone mineral density (BMD) of the proximal femur in a canine model with dual energy x-ray absorptiometry (DXA) was determined. Seven regions of interest, corresponding to zones 1-7 according to Gruen et al., were measured. Eight unpaired femora were scanned with DXA before implantation (five separate scans per femur), after press-fitting with a titanium alloy femoral component (five separate scans per femur); and after cementing with the same component (five separate scans per femur). When the titanium alloy endoprosthesis was press-fit, the BMD of five of seven regions of the proximal femur increased significantly (range, 2.7-23.1%; mean, 11.2%), although the mean precision error of this measurement was not altered (before implantation, 1.1%; after press-fit 1.8%). Cementing of the implant caused a variable effect on BMD, resulting in a decrease in distal regions where cortical bone was relatively thin compared with the cement mantle (regions 3, 4, and 5) and in an increase in the other regions. Cementing of the implant significantly increased the mean precision error of measurement to 7.2% (range, 1.1-12.6%).
通过双能X线吸收法（DXA）测定了压配式和骨水泥固定钛合金假体对犬近端股骨骨密度（BMD）测量的影响。测量了7个感兴趣区域，根据Gruen等人的方法对应于1-7区。在植入前（每侧股骨进行5次单独扫描）、用钛合金股骨部件进行压配后（每侧股骨进行5次单独扫描）以及用相同部件进行骨水泥固定后（每侧股骨进行5次单独扫描），对8对未配对的股骨进行DXA扫描。当钛合金假体进行压配时，近端股骨7个区域中的5个区域的骨密度显著增加（范围为2.7%-23.1%；平均为11.2%），尽管该测量的平均精度误差未改变（植入前为1.1%；压配后为1.8%）。假体的骨水泥固定对骨密度产生了可变的影响，导致与骨水泥套相比皮质骨相对较薄的远端区域（3、4和5区）骨密度降低，而其他区域骨密度增加。假体的骨水泥固定显著增加了测量的平均精度误差至7.2%（范围为1.1%-12.6%）。
