Schwartz Herbert E, Matava Matthew J, Proch Frank S, Butler Charles A, Ratcliffe Anthony, Levy Martin, Butler David L
Noyes Tissue Engineering and Biomechanics Laboratories, Department of Biomedical Engineering, University of Cincinnati, Ohio, USA.
Am J Sports Med. 2006 Nov;34(11):1747-55. doi: 10.1177/0363546506288851. Epub 2006 May 30.
High levels of gamma irradiation are required to eliminate the risk of bacterial and viral transmission during implantation of musculoskeletal allografts. The effects of high levels of gamma irradiation on anterior cruciate ligament allograft biomechanics are still not known.
High-dose gamma irradiation (4 Mrad) adversely affects anterior cruciate ligament allograft biomechanics at surgery and at 6 months after surgery and affects biochemistry at 6 months.
Controlled laboratory study.
Bilateral anterior cruciate ligament reconstructions were performed in 18 adult goats, with one knee receiving an irradiated patellar tendon allograft (4 Mrad) and the other receiving a frozen control allograft (0 Mrad). In 6 recipients (time zero group), graft pairs were tested immediately after sacrifice, and load relaxation of the femur-allograft-tibia preparation was measured during cyclic anterior displacement. Twelve recipients received bilateral anterior cruciate ligament reconstructions, staged 2 months apart, and were sacrificed a mean of 6 months postoperatively. Load relaxation and tensile failure testing were performed, followed by allograft biochemistry assessment.
At time zero, irradiated grafts showed less load relaxation than did contralateral controls, but by 6 months, the trend had reversed because of decreases in control graft relaxation, with no changes in irradiated graft relaxation. By 6 months, irradiated grafts showed lower stiffness and maximum force compared to controls but no differences in modulus, maximum stress, or biochemistry.
High levels of gamma irradiation affect anterior cruciate ligament allograft subfailure viscoelastic and structural properties but not material or biochemical properties over time.
Although high levels of gamma irradiation may inactivate infectious agents, this treatment is not a feasible clinical option because of altered allograft biomechanics.
在植入肌肉骨骼同种异体移植物期间，需要高水平的伽马射线照射以消除细菌和病毒传播的风险。高水平伽马射线照射对前交叉韧带同种异体移植物生物力学的影响尚不清楚。
高剂量伽马射线照射（4兆拉德）会对手术时以及术后6个月的前交叉韧带同种异体移植物生物力学产生不利影响，并在6个月时影响生物化学。
对照实验室研究。
对18只成年山羊进行双侧前交叉韧带重建，一侧膝关节接受辐照的髌腱同种异体移植物（4兆拉德），另一侧接受冷冻对照同种异体移植物（0兆拉德）。在6只受体（零时组）中，在处死后立即测试移植物对，在循环前向移位期间测量股骨-同种异体移植物-胫骨制剂的负荷松弛。12只受体接受双侧前交叉韧带重建，分2个月进行，术后平均6个月处死。进行负荷松弛和拉伸破坏试验，随后进行同种异体移植物生物化学评估。
在零时，辐照移植物的负荷松弛比侧对照移植物少，但到6个月时，由于对照移植物松弛减少，趋势发生逆转，辐照移植物松弛无变化。到6个月时，与对照相比，辐照移植物的刚度和最大力较低，但模量、最大应力或生物化学无差异。
高水平伽马射线照射会影响前交叉韧带同种异体移植物的亚失效粘弹性和结构特性，但随着时间的推移不会影响材料或生物化学特性。
尽管高水平伽马射线照射可能使感染因子失活，但由于同种异体移植物生物力学改变，这种治疗不是可行的临床选择。
