Sonoda Kazuhiko, Yamamoto Takuaki, Motomura Goro, Karasuyama Kazuyuki, Kubo Yusuke, Iwamoto Yukihide
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Skeletal Radiol. 2016 Nov;45(11):1515-21. doi: 10.1007/s00256-016-2462-z. Epub 2016 Aug 24.
Our aims were to investigate the imaging appearance of subchondral insufficiency fracture (SIF) of the femoral head based on fat-suppressed T2-weighted MRI, and evaluate its correlation with the clinical outcomes following conservative treatment.
We retrospectively evaluated 40 hips in 37 patients with SIF of the femoral head (12 males and 25 females; mean age 55.8 years, range 22-78 years). MRI examinations were performed within 3 months after the onset of hip pain. Using fat-suppressed T2-weighted imaging, we evaluated the hips for the intensity of the subchondral bone (corresponding to the area superior to the low intensity band on T1-weighted images) as well as bone marrow edema, joint effusion, and presence of the band lesion. We then correlated the intensity of the subchondral bone with clinical outcomes.
The hips were classified into three types based on subchondral intensity on fat-suppressed T2-weighted images: type 1 (21 hips) showed high intensity, type 2 (eight hips) showed heterogeneous intensity, and type 3 (11 hips) showed low intensity. The mean period between pain onset and MRI examination was significantly longer for type 2 hips than for type 1. Healing rates were 86 % for type 1, 75 % for type 2, and 18 % for type 3.
SIF cases were classified into three types based on subchondral intensity on fat-suppressed T2-weighted imaging performed within 3 months after pain onset. Type 3 SIF tended to be intractable to conservative treatment compared to type 1 and type 2.
本研究旨在基于脂肪抑制T2加权MRI探讨股骨头软骨下不全骨折（SIF）的影像学表现，并评估其与保守治疗后临床结果的相关性。
我们回顾性评估了37例股骨头SIF患者的40个髋关节（男性12例，女性25例；平均年龄55.8岁，范围22 - 78岁）。在髋关节疼痛发作后3个月内进行MRI检查。利用脂肪抑制T2加权成像，我们评估髋关节软骨下骨的强度（对应于T1加权图像上低强度带上方的区域）以及骨髓水肿、关节积液和带状病变的存在情况。然后将软骨下骨的强度与临床结果进行相关性分析。
根据脂肪抑制T2加权图像上的软骨下强度，髋关节分为三种类型：1型（21个髋关节）表现为高强度，2型（8个髋关节）表现为不均匀强度，3型（11个髋关节）表现为低强度。2型髋关节疼痛发作至MRI检查的平均时间明显长于1型。1型愈合率为86%，2型为75%，3型为18%。
根据疼痛发作后3个月内进行的脂肪抑制T2加权成像上的软骨下强度，SIF病例分为三种类型。与1型和2型相比，3型SIF对保守治疗往往难以奏效。
