McCarthy J A, Steadman J R, Dunlap J, Shively R, Stonebrook S
Washington University Hospital, St. Louis, Missouri.
Am J Sports Med. 1990 Jan-Feb;18(1):43-9. doi: 10.1177/036354659001800108.
The potential for a rigidly fixed synthetic graft placed in the over-the-top position to be stress shielding/stress sharing with the patellar tendon autograft was assessed in a primate model. A patellar tendon autograft was placed anatomically and tensioned at 2 pounds for all of the groups. In the augmented animals, a 30 strand braided graft 10 cm in length of expanded polytetrafluoroethylene was tightened with the knee in full extension. After 6 months of unrestricted cage activity the animals were sacrificed and biomechanical testing performed. The augmented patellar tendon autografts demonstrated less laxity in extension as compared to the autografts alone. A minimal decrease in the load and stiffness to failure for the augmented groups as compared to the nonaugmented knees was noted. However, both the reconstruction groups had a significant decrease in the load to failure at 6 months (50% of the normal ACL). In summary, this study demonstrated that a synthetic graft augmentation can be performed in the over-the-top position and minimize knee laxity, especially during terminal extension. With this technique, the laxity was minimized while the incorporation and strengthening of the biologic autograft occurred at a rate similar to the unaugmented reconstruction.
在灵长类动物模型中评估了置于上方位置的刚性固定合成移植物与髌腱自体移植物发生应力屏蔽/应力分担的可能性。所有组的髌腱自体移植物均按解剖位置放置并以2磅的张力拉紧。在增强组动物中，将一段长度为10厘米、由30股编织而成的膨体聚四氟乙烯移植物在膝关节完全伸直时收紧。在无限制的笼养活动6个月后，处死动物并进行生物力学测试。与单纯自体移植物相比，增强后的髌腱自体移植物在伸直时的松弛度更小。与未增强的膝关节相比，增强组的破坏负荷和刚度略有下降。然而，两个重建组在6个月时的破坏负荷均显著下降（为正常前交叉韧带的50%）。总之，本研究表明，合成移植物增强可在上方位置进行，并可最大程度减少膝关节松弛，尤其是在终末伸直时。采用该技术，在使松弛度最小化的同时，生物自体移植物的整合和强化速度与未增强的重建相似。
