Bagnolesi P, Cilotti A, Battolla L, Ortori S, Mascalchi M, Falaschi F, Zampa V, Spinelli M
Cattedra di Radiologia, Università degli Studi di Pisa.
Radiol Med. 1993 Jul-Aug;86(1-2):81-8.
MRI of the knee was performed in 30 patients who had been submitted to arthroscopically-guided reconstruction of the anterior cruciate ligament from patellar tendon. The autograft structure was investigated and MR results were correlated with clinical findings. Partial/total meniscectomy had been carried out in 21/30 cases. The patients were imaged at various postoperative intervals (3-24 months) by means of an 0.5-T magnet (GE MR Max Plus) in full knee extension and internal rotation. Sagittal and axial T1-weighted images (slice thickness: 3 mm) were combined with real-time reconstruction which better demonstrated the whole graft. T2-weighted coronal images (slice thickness: 5 mm) were also acquired. In each patient the following clinical variables were considered: anterior drawer sign, Lachman test, pivot shift, degree of leg extension, and finally functional recovery. The following MR variables were then considered: structure and alignment of bone tunnels, structure and signal intensity of the graft, degree of synovial inflammation, structure and signal intensity of the posterior cruciate ligament and finally structure of the menisci and/or meniscal residues. Symptoms-MR correlation suggests that the different outcome of surgical reconstruction may depend on the correct alignment of the tibial and femoral bone tunnels and on good meniscal condition. Bone tunnels must be located on the same plane, posterior and parallel to the slope of the intercondylar roof, since angulation causes the latter to impact the graft during knee extension, with inflammation and risk for rupture. As for menisci, tiny residues or total ablation overload tha graft, whose signal increases and whose synovia becomes inflamed. The latter pattern is always distinguished from that of the autograft, whose signal intensity seems not to change in time. In conclusion, MR proved an accurate and non-invasive technique to image this kind of postoperative knee, since metallic artifacts do not reach the joint space.
对30例接受经关节镜引导下髌腱重建前交叉韧带手术的患者进行了膝关节磁共振成像（MRI）检查。对自体移植物结构进行了研究，并将MRI结果与临床发现进行了关联分析。21/30例患者进行了部分/全半月板切除术。患者在术后不同时间间隔（3 - 24个月）采用0.5T磁体（GE MR Max Plus）进行成像，成像时膝关节完全伸直并内旋。矢状面和横断面T1加权像（层厚：3mm）结合实时重建，能更好地显示整个移植物。还采集了T2加权冠状面图像（层厚：5mm）。在每位患者中，考虑了以下临床变量：前抽屉试验、拉赫曼试验、轴移试验、伸膝程度，最后是功能恢复情况。然后考虑了以下MRI变量：骨隧道的结构和对线情况、移植物的结构和信号强度、滑膜炎症程度、后交叉韧带的结构和信号强度，最后是半月板和/或半月板残余物的结构。症状与MRI的相关性表明，手术重建的不同结果可能取决于胫骨和股骨骨隧道的正确对线以及半月板的良好状态。骨隧道必须位于同一平面上，在髁间顶斜坡后方且与之平行，因为成角会导致在膝关节伸展时髁间顶撞击移植物，引发炎症并增加破裂风险。至于半月板，微小的残余物或完全切除会使移植物负担过重，移植物信号增强且滑膜发炎。后一种情况总是与自体移植物的情况不同，自体移植物的信号强度似乎不会随时间变化。总之，由于金属伪影不会影响关节间隙，MRI被证明是一种准确且无创的技术，可用于对这类膝关节术后情况进行成像。
