Bellelli A, Adriani E, Maresca G, Nardis P F, Mariani P P
Radiologia Diagnostica, Ospedale, San Pietro Fatebenefratelli, Roma.
Radiol Med. 1997 Jan-Feb;93(1-2):33-9.
Posterior cruciate ligament (PCL) tears are definitely less common than anterior cruciate ligament (ACL) tears: their incidence in literature ranges 3-20% of all capsuloligamentous injuries versus 45-90% for ACL tears. Recent papers reported that if these injuries are not operated on, they evolve first into medial femorotibial and femoropatellar arthrosis and then into tricompartmental arthrosis. There are several MR studies dealing with ACL reconstruction, while MR studies on PCL reconstruction are lacking, both because the frequency of the latter injuries is lower and because they are difficult to demonstrate. We report our preliminary experience with PCL reconstruction studied with MRI in 12 patients submitted to arthroscopy. We used the ipsilateral patellar tendon (11 cases) or the contralateral one (1 case). The patients were submitted to MRI 4-16 months after surgery. Axial, coronal and sagittal images were acquired, together with oblique sagittal and coronal slices to show the graft completely. We also used SE, GE and fat suppression STIR MR sequences, trying to identify which of them are the most useful in patients with healing or exudative reaction in the intercondylar notch. MR exams were performed with a dedicated permanent magnet (0.2 T) and a permanent total body unit (0.3 T). The graft was clearly depicted on all images in 11 patients, while graft retear was shown in 1 patient. MRI did depict the whole graft in all patients, which finding is useful to study the signal intensity changes which indicate graft trophism. MRI also depicted correctly the femoral and tibial tunnel position and alignment, the presence of possible impingement with bone, the presence and extent of the healing reaction or of serum-hematic material in the intercondylar notch. The latter factor prevents the graft depiction, in which case the MR techniques providing the highest possible contrast in the different structures under examination are mandatory. Finally, MRI permitted to study possible associated capsuloligamentous or meniscal injuries and the state of femorotibial and femoropatellar chondral covering, the presence of articular synovia changes and the amount of possible joint effusion. We believe that MRI exhibited a high standard of sensitivity, versatility and diagnostic accuracy in the examination of surgical patients submitted to arthroscopic PCL reconstruction. Further studies and long-term follow-up will help define the use of MRI in these patients.
后交叉韧带（PCL）撕裂肯定比前交叉韧带（ACL）撕裂少见：文献报道其在所有关节囊韧带损伤中的发生率为3% - 20%，而ACL撕裂的发生率为45% - 90%。近期论文报道，如果这些损伤不进行手术治疗，它们首先会发展为股胫内侧和股髌关节骨性关节炎，然后发展为全关节腔骨性关节炎。有多项关于ACL重建的磁共振成像（MR）研究，而关于PCL重建的MR研究却很缺乏，这既是因为后一种损伤的发生率较低，也是因为它们难以显示。我们报告了对12例接受关节镜检查的患者进行PCL重建后用MRI研究的初步经验。我们使用了同侧髌腱（11例）或对侧髌腱（1例）。患者在术后4 - 16个月接受MRI检查。采集了轴位、冠状位和矢状位图像，以及斜矢状位和冠状位切片以完整显示移植物。我们还使用了自旋回波（SE）、梯度回波（GE）和脂肪抑制短反转恢复（STIR）MR序列，试图确定它们中哪些对髁间切迹有愈合或渗出反应的患者最有用。MR检查使用了专用永磁体（0.2T）和全身永磁单元（0.3T）。11例患者的移植物在所有图像上均清晰显示，1例患者显示移植物再撕裂。MRI确实在所有患者中显示了整个移植物，这一发现有助于研究表明移植物营养状况的信号强度变化。MRI还正确显示了股骨和胫骨隧道的位置及对线情况、与骨可能存在的撞击、髁间切迹愈合反应或血清血液物质的存在及范围。后一个因素会妨碍移植物的显示，在这种情况下，必须采用能在检查的不同结构中提供尽可能高对比度的MR技术。最后，MRI能够研究可能存在的相关关节囊韧带或半月板损伤以及股胫和股髌软骨覆盖情况、关节滑膜变化情况以及可能的关节积液量。我们认为，在对接受关节镜下PCL重建的手术患者进行检查时，MRI表现出了很高的敏感性、多功能性和诊断准确性。进一步的研究和长期随访将有助于确定MRI在这些患者中的应用。
