Wang Huizhi, Tao Mingzhu, Shi Qinyi, He Kaixin, Cheng Cheng-Kung
School of Biomedical Engineering and Engineering Research Center for Digital Medicine of the Ministry of Education, Shanghai Jiao Tong University, Shanghai 200030, China.
Bioengineering (Basel). 2022 Sep 27;9(10):507. doi: 10.3390/bioengineering9100507.
The size of the anterior cruciate ligament (ACL) often varies between individuals, but such variation is not typically considered during ACL reconstruction (ACLR). This study aimed to explore how the size of the ACL affects the selection of a suitable graft diameter. A finite element model of a human knee was implanted with intact ACLs of different dimensions (0.95, 1 and 1.05 times the size of the original ACL) and with grafts of different diameters, to simulate ACLR (diameter 7.5-12 mm in 0.5 mm increments). The knee models were flexed to 30° and loaded with an anterior tibial load of 103 N, internal tibial moment of 7.5 Nm, and valgus tibial moment of 6.9 Nm. Knee kinematics (anterior tibial translation (ATT), internal tibial rotation (ITR) and valgus tibial rotation (VTR)) and ligament forces were recorded and compared among the different groups. The results showed that, compared with the intact knee, a graft diameter of 7.5 mm was found to increase the ATT and VTR, but reduce the graft force. Increasing the graft diameter reduced knee laxity and increased the graft force. A 10% increase in the size of the ACL corresponded to a 3 mm larger graft diameter required to restore knee stability and graft force after ACLR. It was concluded that the graft diameter should be selected according to the dimensions of the native ACL, for better restoration of knee functionality. This study may help to improve the clinical treatment of ACL ruptures.
前交叉韧带（ACL）的大小在个体之间通常存在差异，但在ACL重建（ACLR）过程中，这种差异通常未被考虑。本研究旨在探讨ACL的大小如何影响合适移植物直径的选择。将不同尺寸（原始ACL大小的0.95、1和1.05倍）的完整ACL以及不同直径的移植物植入人体膝关节的有限元模型中，以模拟ACLR（直径7.5 - 12 mm，增量为0.5 mm）。将膝关节模型屈曲至30°，并施加103 N的胫骨前向负荷、7.5 Nm的胫骨内力矩和6.9 Nm的胫骨外翻力矩。记录并比较不同组之间的膝关节运动学指标（胫骨前向平移（ATT）、胫骨内旋（ITR）和胫骨外翻旋转（VTR））以及韧带力。结果表明，与完整膝关节相比，发现7.5 mm的移植物直径会增加ATT和VTR，但会降低移植物力。增加移植物直径可减少膝关节松弛并增加移植物力。ACL大小增加10%对应于ACLR后恢复膝关节稳定性和移植物力所需的移植物直径增大3 mm。得出的结论是，应根据天然ACL的尺寸选择移植物直径，以更好地恢复膝关节功能。本研究可能有助于改善ACL断裂的临床治疗。
