Gibbons M J, Butler D L, Grood E S, Bylski-Austrow D I, Levy M S, Noyes F R
Noyes-Giannestras Biomechanics Laboratories, Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Ohio 45221-0048.
J Orthop Res. 1991 Mar;9(2):209-18. doi: 10.1002/jor.1100090209.
The effects of 60Co gamma irradiation on the initial mechanical properties of the composite bone-patellar tendon-bone unit (CU) and the tendon midsubstance (TM) were studied. Frozen specimens were exposed to either 2 or 3 Mrad of gamma irradiation. Paired frozen specimens served as intraanimal controls. Treatment effects on the CU were assessed using four mechanical parameters. Effects on the TM were assessed using four material parameters measured using an optical surface-strain analysis system. The maximum force and strain energy to maximum force of the composite unit were significantly reduced 27% and 40%, respectively, after 3 Mrad of irradiation (p less than .05). Mechanical properties of the CU were not significantly altered, however, following 2 Mrad of irradiation. Based on individual paired contrasts between treatment and control, significant differences were also found in the material properties of the tendon midsubstance. The maximum stress, maximum strain, and strain energy density to maximum stress were significantly reduced following 3 Mrad, but not 2 Mrad, of irradiation. The results provide important "time zero" material property data, which will be useful for later anterior cruciate ligament reconstruction studies using irradiated allograft patellar tendons in the goat model and other animal models as well.
研究了60Coγ射线辐照对复合骨-髌腱-骨单元（CU）和肌腱中间部分（TM）初始力学性能的影响。将冷冻标本暴露于2或3兆拉德的γ射线辐照下。配对的冷冻标本用作动物体内对照。使用四个力学参数评估对CU的处理效果。使用光学表面应变分析系统测量的四个材料参数评估对TM的影响。在3兆拉德辐照后，复合单元的最大力和达到最大力时的应变能分别显著降低了27%和40%（p小于0.05）。然而，在2兆拉德辐照后，CU的力学性能没有显著改变。基于处理组与对照组之间的个体配对对比，在肌腱中间部分的材料性能方面也发现了显著差异。在3兆拉德而非2兆拉德辐照后，最大应力、最大应变以及达到最大应力时的应变能密度显著降低。这些结果提供了重要的“零时间”材料性能数据，这对于以后在山羊模型和其他动物模型中使用辐照后的同种异体髌腱进行前交叉韧带重建研究将是有用的。
