Wan Fang, Chen Tianwu, Ge Yunshen, Zhang Peng, Chen Shiyi
Department of Orthopedic Sports Medicine, Huashan Hospital, Shanghai, China.
Fudan University Sports Medicine Institute, Shanghai, China.
Orthop J Sports Med. 2019 Dec 31;7(12):2325967119890382. doi: 10.1177/2325967119890382. eCollection 2019 Dec.
In anterior cruciate ligament (ACL) reconstruction, minimizing the graft-tunnel motion (GTM) will promote graft-to-bone healing and avoid graft loosening or tearing as well as potential bone tunnel enlargement. A nearly isometric state of the graft can be achieved by placing the tunnel properly to theoretically gain better graft-to-bone healing. However, little clinical evidence is available to quantify the relation between GTM and tunnel position.
To find the proper zones for the femoral and tibial tunnel apertures that minimize the GTM, referred to as the "nearly isometric zone," through use of intraoperative GTM measurement and 3-dimensional computed tomography (3D-CT).
Cross-sectional study; Level of evidence, 3.
A total of 100 patients were enrolled in this study. Nearly isometric ACL reconstruction was performed, and an intra-articular GTM measuring device was designed to measure and record the amplitude of GTM while the knee was flexed from 0° to 120°. Postoperatively, the patients underwent multislice CT, and the images were used to create 3D-CT models. After tibial aperture examination, 5 patients were excluded due to the divergence of tibial aperture, and therefore 95 patients remained in the study. Patients were divided into 2 groups according to whether the lateral intercondylar ridge was absent or present. The Bernard-Hertel grid coordinates () of the femoral tunnel were then quantified.
The maximal GTM (mGTM) was a mean ± SD of 1.06 ± 0.66 mm (range, 0.0-3.0 mm). The mGTM in patients with a lateral intercondylar ridge was significantly lower than that in patients without a lateral intercondylar ridge (0.81 ± 0.39 vs 1.59 ± 0.73 mm, respectively; < .0001). The average and were 0.227 ± 0.079 and 0.429 ± 0.770, respectively. Notably, in 1 patient, the mGTM was 0 mm whereas the coordinates () of the femoral tunnel were 0.250 and 0.255. The overall GTM slowly increased before 90° but increased significantly after the knee was bent 105° ( = .010). Correlation analysis showed that the coordiinate had significant correlation with mGTM ( = 0.581; < .001). A gradient pattern was created to show the nearly isometric blue zone (mGTM <0.5 mm), which was found to overlap with the IDEAL (isometric, direct insertion, eccentric, anatomic, low tension-flexion pattern) position.
A method of measuring intraoperative GTM and quantifying femoral tunnel position on postoperative 3D-CT was successfully developed. The presence of a lateral condylar ridge can significantly reduce mGTM. A nearly isometric zone was described that was consistent with the IDEAL concept.
在前交叉韧带（ACL）重建中，最小化移植物-骨隧道运动（GTM）将促进移植物与骨的愈合，避免移植物松动或撕裂以及潜在的骨隧道扩大。通过正确放置隧道理论上可实现移植物的近等长状态，从而获得更好的移植物与骨的愈合。然而，几乎没有临床证据可量化GTM与隧道位置之间的关系。
通过术中GTM测量和三维计算机断层扫描（3D-CT），找到使GTM最小化的股骨和胫骨隧道开口的合适区域，即“近等长区”。
横断面研究；证据等级，3级。
本研究共纳入100例患者。进行了近等长ACL重建，并设计了一种关节内GTM测量装置，用于在膝关节从0°屈曲至120°时测量和记录GTM的幅度。术后，患者接受多层CT检查，图像用于创建3D-CT模型。在检查胫骨开口后，由于胫骨开口发散排除了5例患者，因此95例患者留在研究中。根据外侧髁间嵴是否存在将患者分为2组。然后对股骨隧道的伯纳德-赫特尔网格坐标（）进行量化。
最大GTM（mGTM）的平均值±标准差为1.06±0.66mm（范围，0.0 - 3.0mm）。有外侧髁间嵴的患者的mGTM显著低于没有外侧髁间嵴的患者（分别为0.81±0.39和1.59±0.73mm；<0.0001）。平均和分别为0.227±0.079和0.429±0.770。值得注意的是，1例患者的mGTM为0mm，而股骨隧道的坐标（）为0.250和0.255。总体GTM在90°之前缓慢增加，但在膝关节弯曲105°后显著增加（=0.010）。相关性分析表明坐标与mGTM有显著相关性（=0.581；<0.001）。创建了一个梯度模式以显示近等长蓝色区域（mGTM<0.5mm），发现其与理想（等长、直接插入、偏心、解剖、低张力-屈曲模式）位置重叠。
成功开发了一种术中测量GTM并在术后3D-CT上量化股骨隧道位置的方法。外侧髁嵴的存在可显著降低mGTM。描述了一个与理想概念一致的近等长区。
