Costi John J, Edmonds-Wilson Rohan H, Howie Donald W, Stamenkov Roumen, Field John R, Stanley Richard M, Hearn Trevor C, Callary Stuart A, McGee Margaret A
Biomechanics & Implants Research Group, The Medical Device Research Institute, Flinders University, South Australia, Australia.
Clin Biomech (Bristol). 2013 Aug;28(7):770-6. doi: 10.1016/j.clinbiomech.2013.07.003. Epub 2013 Jul 26.
A gamma irradiation dose of 15kGy has been shown to adequately sterilise allograft bone, commonly used in femoral impaction bone grafting to treat bone loss at revision hip replacement, without significantly affecting its mechanical properties. The objective of this study was to evaluate whether use of 15kGy irradiated bone affects the initial mechanical stability of the femoral stem prosthesis, as determined by micromotion in a comprehensive testing apparatus, in a clinically relevant time zero in vitro model of revision hip replacement.
Morselised ovine bone was nonirradiated (control), or irradiated at 15kGy or 60kGy. For each dose, six ovine femurs were implanted with a cemented polished taper stem following femoral impaction bone grafting. Using testing apparatus that reproduces stem loading, stems were cyclically loaded and triaxial micromotion of the stem relative to the bone was measured at the proximal and distal stem regions using non-contact laser transducers and linear variable differential transformers.
There were no significant differences in proximal or distal stem micromotion between groups for all directions (p≤0.80), apart for significantly greater distal stem medial-lateral micromotion in the 60kGy group compared to the 15kGy group (P=0.03), and near-significance in the anterior-posterior direction (P=0.08, power=0.85).
Using a clinically relevant model and loading apparatus, irradiation of bone at 15kGy does not affect initial femoral stem stability following femoral impaction bone grafting.
已证明15千戈瑞的伽马辐射剂量能充分对同种异体骨进行灭菌处理，同种异体骨常用于股骨打压植骨以治疗髋关节翻修置换时的骨缺损，且不会显著影响其力学性能。本研究的目的是评估在髋关节翻修置换的临床相关零时体外模型中，使用15千戈瑞辐射骨是否会影响股骨柄假体的初始力学稳定性，该稳定性通过在综合测试设备中测量微动来确定。
将碎羊骨分为未辐照组（对照组）、15千戈瑞辐照组和60千戈瑞辐照组。对于每个剂量组，在股骨打压植骨后，向六只羊的股骨植入骨水泥固定的抛光锥形柄。使用能模拟柄部负荷的测试设备，对柄部进行循环加载，并使用非接触式激光传感器和线性可变差动变压器在柄部近端和远端区域测量柄相对于骨的三轴微动。
除60千戈瑞组与15千戈瑞组相比远端柄部内外侧微动显著更大（P = 0.03）以及前后方向接近显著差异（P = 0.08，检验效能 = 0.85）外，各组在所有方向上近端或远端柄部微动均无显著差异（p≤0.80）。
使用临床相关模型和加载设备，15千戈瑞剂量的骨辐照不会影响股骨打压植骨后股骨柄的初始稳定性。
