Unité d'orthopédie et traumatologie du sport, Service de chirurgie orthopédique et traumatologie de l'appareil moteur, University Hospital of Geneva, Genève, Switzerland.
Knee Surg Sports Traumatol Arthrosc. 2010 Apr;18(4):463-71. doi: 10.1007/s00167-010-1053-0. Epub 2010 Feb 11.
Articular cartilage and the subchondral bone act as a functional unit. Following trauma, osteochondritis dissecans, osteonecrosis or osteoarthritis, this intimate connection may become disrupted. Osteochondral defects-the type of defects that extend into the subchondral bone-account for about 5% of all articular cartilage lesions. They are very often caused by trauma, in about one-third of the cases by osteoarthritis and rarely by osteochondritis dissecans. Osteochondral defects are predominantly located on the medial femoral condyle and also on the patella. Frequently, they are associated with lesions of the menisci or the anterior cruciate ligament. Because of the close relationship between the articular cartilage and the subchondral bone, imaging of cartilage defects or cartilage repair should also focus on the subchondral bone. Magnetic resonance imaging is currently considered to be the key modality for the evaluation of cartilage and underlying subchondral bone. However, the choice of imaging technique also depends on the nature of the disease that caused the subchondral bone lesion. For example, radiography is still the golden standard for imaging features of osteoarthritis. Bone scintigraphy is one of the most valuable techniques for early diagnosis of spontaneous osteonecrosis about the knee. A CT scan is a useful technique to rule out a possible depression of the subchondral bone plate, whereas a CT arthrography is highly accurate to evaluate the stability of the osteochondral fragment in osteochondritis dissecans. Particularly for the problem of subchondral bone lesions, image evaluation methods need to be refined for adequate and reproducible analysis. This article highlights recent studies on the epidemiology and imaging of the subchondral bone, with an emphasis on magnetic resonance imaging.
关节软骨和软骨下骨作为一个功能单位。在创伤、剥脱性骨软骨炎、骨坏死或骨关节炎后，这种密切的联系可能会被打破。骨软骨缺损——即延伸至软骨下骨的类型的缺损——约占所有关节软骨病变的 5%。它们通常由创伤引起，约三分之一的病例由骨关节炎引起，很少由剥脱性骨软骨炎引起。骨软骨缺损主要位于股骨内侧髁和髌骨上。它们经常与半月板或前交叉韧带的损伤有关。由于关节软骨和软骨下骨之间的密切关系，软骨缺损或软骨修复的影像学检查也应侧重于软骨下骨。磁共振成像（MRI）目前被认为是评估软骨和软骨下骨的关键方式。然而，成像技术的选择也取决于导致软骨下骨病变的疾病性质。例如，X 线摄影仍然是评估骨关节炎特征的金标准。骨闪烁显像术是早期诊断膝关节自发性骨坏死的最有价值的技术之一。CT 扫描是排除软骨下骨板可能凹陷的有用技术，而 CT 关节造影术对评估剥脱性骨软骨炎中骨软骨碎片的稳定性非常准确。特别是对于软骨下骨病变的问题，需要改进图像评估方法，以便进行充分和可重复的分析。本文重点介绍了软骨下骨的流行病学和影像学研究的最新进展，强调了磁共振成像。
