Currey J D, Foreman J, Laketić I, Mitchell J, Pegg D E, Reilly G C
Department of Biology, University of York, England, U.K.
J Orthop Res. 1997 Jan;15(1):111-7. doi: 10.1002/jor.1100150116.
Allogeneic bone grafts are frequently sterilized by means of ionizing radiation. We investigated the effects of ionizing radiation on both quasistatic and impact mechanical properties of human bone. Specimens from four paired femora of four donors received doses of 29.5 kGy ("standard," frequently used by tissue banks), 94.7 kGy ("high"), or 17 kGy ("low") of ionizing radiation. Young's modulus was unchanged by any level of radiation. Radiation significantly reduced bending strength, work to fracture, and impact energy absorption; in each case, the severity of the effect increased from low to standard to high doses of radiation. Work to fracture was particularly severely degraded; specimens irradiated with the high dose absorbed only 5% of the energy of the controls. Radiation, even at relatively low doses, makes the bone more brittle and thereby reduces its energy-absorbing capacity. We suggest that because the level of radiation required to produce an acceptable level of viral inactivation (90 kGy) produces an unacceptable reduction in the mechanical integrity of the bone, low levels of radiation, sufficient to produce bacterial safety, should be used in conjunction with biological tests to ensure viral safety.
同种异体骨移植物通常通过电离辐射进行灭菌。我们研究了电离辐射对人骨的准静态和冲击力学性能的影响。来自四名捐赠者的四对股骨标本接受了29.5千戈瑞（“标准剂量”，组织库常用）、94.7千戈瑞（“高剂量”）或17千戈瑞（“低剂量”）的电离辐射。任何辐射水平都未改变杨氏模量。辐射显著降低了弯曲强度、断裂功和冲击能量吸收；在每种情况下，效应的严重程度从低剂量到标准剂量再到高剂量逐渐增加。断裂功尤其严重下降；高剂量照射的标本仅吸收了对照标本能量的5%。即使是相对低剂量的辐射也会使骨头更脆，从而降低其能量吸收能力。我们认为，由于产生可接受水平的病毒灭活所需的辐射水平（90千戈瑞）会导致骨的机械完整性出现不可接受的降低，因此应使用足以确保细菌安全的低水平辐射，并结合生物学检测以确保病毒安全。
