Abstract：
UNASSIGNED: Synthetic grafts have been used for a number of years in anterior cruciate ligament (ACL) reconstruction surgery. One of the more recent additions to the stable of synthetic ligaments is the Ligament Augmentation and Reconstruction System (LARS) ligament.
UNASSIGNED: To analyze the biomechanics and histology of LARS grafts retrieved due to failure of the device.
UNASSIGNED: Descriptive laboratory study.
UNASSIGNED: A total of 22 LARS ligament grafts that were explanted from patients were sent for analysis. Five new, unused samples of the standard LARS ACL graft were also analyzed. Biomechanical testing was performed: ultimate tensile force, force versus displacement, and stress versus strain were recorded. Histopathological examination was performed looking for degree of fibrous tissue ingrowth as well as the presence of a foreign body reaction.
UNASSIGNED: Of the 22 grafts retrieved, 14 were used for ACL grafts, 1 for a lateral collateral ligament graft, 2 for medial collateral ligament grafts, 4 for gluteal tendon augmentation, and 1 for a supraspinatus augmentation. A severe foreign body reaction was found in 86% of the grafts (18/22) and a mild foreign body reaction in the remaining 14% (4/22). Tissue ingrowth was minimal in the majority of ACL grafts; the other grafts showed moderate tissue ingrowth. Maximal tensile force was significantly higher for the new ACL grafts (mean ± SD, 1667 ± 845 N) compared with the retrieved grafts (897 ± 395 N; P < .05).
UNASSIGNED: This study demonstrated that the vast majority of retrieved LARS artificial ligaments had a florid foreign body reaction. There was minimal tissue ingrowth in ACL grafts and moderate ingrowth in other grafts. Retrieved grafts had a decreased ultimate tensile force, which increased their risk of rupture.
UNASSIGNED: Surgeons should be cautious in choosing to use these grafts in reconstructive surgery for patients.
UNASSIGNED: To analyze the biomechanics and histology of LARS grafts retrieved due to failure of the device.
UNASSIGNED: Descriptive laboratory study.
UNASSIGNED: A total of 22 LARS ligament grafts that were explanted from patients were sent for analysis. Five new, unused samples of the standard LARS ACL graft were also analyzed. Biomechanical testing was performed: ultimate tensile force, force versus displacement, and stress versus strain were recorded. Histopathological examination was performed looking for degree of fibrous tissue ingrowth as well as the presence of a foreign body reaction.
UNASSIGNED: Of the 22 grafts retrieved, 14 were used for ACL grafts, 1 for a lateral collateral ligament graft, 2 for medial collateral ligament grafts, 4 for gluteal tendon augmentation, and 1 for a supraspinatus augmentation. A severe foreign body reaction was found in 86% of the grafts (18/22) and a mild foreign body reaction in the remaining 14% (4/22). Tissue ingrowth was minimal in the majority of ACL grafts; the other grafts showed moderate tissue ingrowth. Maximal tensile force was significantly higher for the new ACL grafts (mean ± SD, 1667 ± 845 N) compared with the retrieved grafts (897 ± 395 N; P < .05).
UNASSIGNED: This study demonstrated that the vast majority of retrieved LARS artificial ligaments had a florid foreign body reaction. There was minimal tissue ingrowth in ACL grafts and moderate ingrowth in other grafts. Retrieved grafts had a decreased ultimate tensile force, which increased their risk of rupture.
UNASSIGNED: Surgeons should be cautious in choosing to use these grafts in reconstructive surgery for patients.
摘要：
■合成移植物已在前交叉韧带（ACL）重建手术中使用多年。合成韧带稳定性的最新补充之一是韧带增强和重建系统（LARS）韧带。
■分析由于设备故障而取回的LARS移植物的生物力学和组织学。
■描述性实验室研究。
■共22例患者移植的LARS韧带移植物被送去分析。五个新的，还分析了标准LARSACL移植物的未使用样品.进行了生物力学测试：极限拉力，力与位移的关系，并记录应力与应变的关系。进行组织病理学检查以寻找纤维组织向内生长的程度以及异物反应的存在。
■在检索到的22个移植物中，14个用于ACL移植物，1用于外侧副韧带移植物，2用于内侧副韧带移植物，4用于臀腱增强，和1用于冈上肌扩张。在86％的移植物中发现了严重的异物反应（18/22），在其余14％中发现了轻度的异物反应（4/22）。大多数ACL移植物的组织向内生长很少；其他移植物显示中等组织向内生长。新ACL移植物的最大拉力明显更高（平均值±SD，1667±845N）与回收的移植物（897±395N；P<.05）相比。
■这项研究表明，绝大多数检索到的LARS人工韧带具有花样的异物反应。ACL移植物的组织向内生长最少，其他移植物的组织向内生长中等。取回的移植物的极限拉力降低，这增加了他们破裂的风险。
■外科医生应谨慎选择将这些移植物用于患者的重建手术。
■分析由于设备故障而取回的LARS移植物的生物力学和组织学。
■描述性实验室研究。
■共22例患者移植的LARS韧带移植物被送去分析。五个新的，还分析了标准LARSACL移植物的未使用样品.进行了生物力学测试：极限拉力，力与位移的关系，并记录应力与应变的关系。进行组织病理学检查以寻找纤维组织向内生长的程度以及异物反应的存在。
■在检索到的22个移植物中，14个用于ACL移植物，1用于外侧副韧带移植物，2用于内侧副韧带移植物，4用于臀腱增强，和1用于冈上肌扩张。在86％的移植物中发现了严重的异物反应（18/22），在其余14％中发现了轻度的异物反应（4/22）。大多数ACL移植物的组织向内生长很少；其他移植物显示中等组织向内生长。新ACL移植物的最大拉力明显更高（平均值±SD，1667±845N）与回收的移植物（897±395N；P<.05）相比。
■这项研究表明，绝大多数检索到的LARS人工韧带具有花样的异物反应。ACL移植物的组织向内生长最少，其他移植物的组织向内生长中等。取回的移植物的极限拉力降低，这增加了他们破裂的风险。
■外科医生应谨慎选择将这些移植物用于患者的重建手术。
