Higashiyama I, Kumai T, Takakura Y, Tamail S
Department of Orthopaedic Surgery, Nara Medical University, Kashihara, Japan.
Foot Ankle Int. 2000 Feb;21(2):127-33. doi: 10.1177/107110070002100206.
Characteristic MRI findings of osteochondral lesions of the talus have been reported. We examined how they change before and after treatment and discussed their significance. Twenty two ankles in 21 patients had MRI examination before and after treatment of the talar lesion. We evaluated the changes in the low intensity areas in T1-weighted image and the signal rims behind osteochondral fragment in T2-weighted image which have been reported as characteristic findings. Clinical symptoms were improved postoperatively in all subjects. The low intensity areas in T1-weighted image seen before the surgical treatment tended to decrease in size postoperatively. The low intensity area in T1-weighted image was reduced in 15 of the 22 ankles (68.2%). Low signal rim in T2-weighted image was seen in three cases before the treatment. All disappeared completely after arthroscopic drilling. Similarly, high signal rim in T2-weighted image seen in 13 cases before the treatment disappeared in 10 postoperatively. These findings were considered indicative that surgical treatments reduced abnormal stress of the underlying bone element due to unstable osteochondral fragment, leading to reduction of the low intensity area. The disappearance of signal rims in T2-weighted images was considered to indicate obliteration of the interface between the osteochondral fragment and the talar bed with bone union. We believe that MRI of the osteochondral lesion of the talus will be useful for postoperative evaluation allowing assessment of the need for further treatment. The decreasing size of low intensity areas in T1-weighted images and disappearance of signal rims behind the osteochondral fragment in T2-weighted images suggested healing of the osteochondral lesions.
距骨骨软骨损伤的特征性MRI表现已有报道。我们研究了这些表现治疗前后的变化并探讨了其意义。21例患者的22个踝关节在距骨损伤治疗前后均接受了MRI检查。我们评估了T1加权图像上低强度区域以及T2加权图像上骨软骨碎片后方信号边缘的变化，这些已被报道为特征性表现。所有受试者术后临床症状均有改善。手术治疗前T1加权图像上可见的低强度区域术后尺寸往往减小。22个踝关节中有15个（68.2%）的T1加权图像上的低强度区域减小。治疗前3例T2加权图像上可见低信号边缘。关节镜钻孔后全部完全消失。同样，治疗前13例T2加权图像上可见的高信号边缘术后10例消失。这些发现被认为表明手术治疗减轻了不稳定骨软骨碎片对下方骨结构的异常应力，导致低强度区域减小。T2加权图像上信号边缘的消失被认为表明骨软骨碎片与距骨床之间的界面因骨愈合而消失。我们认为距骨骨软骨损伤的MRI检查对术后评估有用，可用于评估是否需要进一步治疗。T1加权图像上低强度区域尺寸减小以及T2加权图像上骨软骨碎片后方信号边缘消失提示骨软骨损伤愈合。
