Objectives: Anterior cruciate ligament injury is the most common type of knee joint ligament injury. Anterior cruciate ligament reconstruction has a high failure rate, with bone tunnel abnormalities as the most significant factor in these failures. Digital orthopedic technology can effectively develop implementation plans for the revision, thus increasing the success rate. This study aims to develop a surgical plan for anterior cruciate ligament revision by employing multiplanar reconstruction (MPR) for measuring bone tunnel position and diameter, and simulating bone tunnel creation via 3D printing preoperatively.
Methods: A total of 12 patients who underwent anterior cruciate ligament revision at the Third Xiangya Hospital of Central South University between 2014 and 2021 were retrospectively studied. The data included patient demographics, preoperative formulated knee joint 3D printing models, and preoperative knee CT scans. The study measured the bone tunnel's diameter and position to guide the establishment of revision bone tunnels during surgery, reassessed the postoperative bone tunnels, and evaluated knee joint functional scores [including International Knee Documentation Committee Knee Evaluation Form (IKDC) score, Lysholm score, and Tegner exercise level score].
Results: Preoperative measurements revealed suboptimal femoral tunnels positions in 4 patients and tibial tunnels positions in 2 patients. MPR and 3D printing technology were used to guide the establishment of a new bone canal during surgery, and postoperative measurements were satisfactory for all patients. Preoperative measurements demonstrated the interclass correlation coefficient for femoral tunnels and tibial tunnels diameters were 0.843 (P<0.05) and 0.889 (P<0.001), respectively. Meanwhile, the intraclass correlation coefficient were 0.811 (P<0.05) and 0.784 (P<0.05), respectively. The intraoperative diameter of femoral and tibial tunnels showed excellent correlation with postoperative CT measurements, with intraclass correlation coefficient values of 0.995 (P<0.001) and 0.987 (P<0.001), respectively. All bone tunnel positions were within the normal range. At the final follow-up, knee joint function scores in all 12 patients improved significantly compared to pre-surgery (P<0.001), and the reoperation rate was zero.
Conclusions: MPR and 3D printing technology can accurately measure the parameters of reconstructed anterior cruciate ligament bone tunnels. Personalized revision plans for patients with reconstruction failure enhances the success rate of revision surgery and improves patient prognosis.
目的: 前交叉韧带损伤是膝关节韧带损伤中最常见的类型。韧带重建手术存在较高的失败率，骨道异常被认为是最重要的失败因素。数字骨科技术可以在术前较为精准地制订翻修手术过程中骨道的实施方案，提高翻修手术成功率。本研究术前通过多平面重建(multiplanar reconstruction，MPR)技术测定骨道位置和直径及3D打印模型建立模拟骨道，以制订前交叉韧带翻修术方案。方法: 回顾性选取2014至2021年在中南大学湘雅三医院行前交叉韧带翻修术的12名患者，收集患者的基本信息、术前制订的膝关节3D打印模型及术前膝关节CT数据。测量骨道直径及位置，以此为基础指导术中翻修骨道的建立，并对术后的骨道进行再次测量及对膝关节功能进行评分[包括国际膝关节文献委员会膝关节评估表(the International Knee Documentation Committee Knee Evaluation Form，IKDC)评分、Lysholm评分、Tegner运动等级评分]。结果: 术前通过测量发现4名患者的股骨骨道位置和2名患者的胫骨骨道位置欠佳，通过MPR与3D打印技术指导术中新骨道的建立，术后测量所有患者的骨道位置满意。术前的股骨与胫骨骨道内口直径测量值的组内相关系数分别为0.843(P<0.05)和0.889(P<0.001)，组间相关系数分别为0.811(P<0.05)和0.784(P<0.05)；术中建立的股骨与胫骨骨道内口直径与术后复查CT测量的股骨及胫骨骨道内口直径的组内相关系数分别为0.995(P<0.001)和0.987(P<0.001)。12名患者末次随访的各项膝关节功能评分均较术前明显改善(均P<0.001)，再次手术率为0。结论: MPR与3D打印技术能较为精准、有效地测量前交叉韧带重建骨道参数，为重建失败患者制订个性化的翻修方案，很大程度上保障了翻修手术的成功率，有利于改善患者预后。.
Keywords: 3D printing; anterior cruciate ligament revision; bone tunnel measure; digital orthopedic technologies; multiplanar reconstruction.