Murakami Taiki, Enokida Makoto, Kawaguchi Kei, Otsuki Ryoji, Nagashima Hideki
Department of Orthopedic Surgery, Faculty of Medicine, Tottori University, Yonago, 36-1 Nishimachi, Yonago, Tottori, 683-8504 Japan.
Department of Orthopedic Surgery, Faculty of Medicine, Tottori University, Yonago, 36-1 Nishimachi, Yonago, Tottori, 683-8504 Japan.
J Orthop Sci. 2017 Mar;22(2):318-324. doi: 10.1016/j.jos.2016.11.021. Epub 2016 Dec 27.
Medial radial displacement (MRD) of the medial meniscus is a feature proving a dysfunction in the medial meniscus in osteoarthritis (OA) of the knee. MRD was measured in radiographic pre-OA knee and early osteoarthritis of the knee (early-OA) longitudinally using ultrasound (US) to investigate the characteristics involved in the onset and progression of OA.
Fifty-five patients with pain on the medial side of the knee participated in the present study. It was possible to follow-up 46 patients for 5 years, and, thus, they were divided into 32 pre-OA patients (female: 59%, mean age: 69.0 years) and 14 early-OA patients (female: 78%, mean age: 74.4 years) based on radiography at the baseline time-point. MRD was measured in standing and supine positions at baseline and after 1 and 5 years using US. MRD corrected with the skeletal size, i.e., the medial displacement index (MDI), was analyzed. The pre- and early-OA groups were divided into subgroups at 5 years: stable and OA progression groups, following the Kellgren/Lawrence classification, and ⊿MDI (gap of the MDI between the standing and supine positions) were retrospectively compared between the subgroups at baseline, 1 and 5 years.
In the overall pre-OA group, MDI increased by 7% and 10% at 5 years in the supine and standing position, showing a significant increase (P = 0.044, 0.0147). ⊿MDI was significantly greater in the subgroup with OA progression in the pre- and early-OA groups (P = 0.02 and 0.03, respectively), and was continuously 6-7% in the pre-OA progression group, showing that the displacement rate was 2-fold or higher than in the stable group.
An increase in ⊿MDI on US may be an important risk factor for the disease stage progression of OA and useful as a feature predicting the onset of radiographic knee OA.
内侧半月板的内侧径向位移（MRD）是膝关节骨关节炎（OA）中内侧半月板功能障碍的一个特征。在膝关节OA前期和早期骨关节炎（早期OA）的影像学检查中，使用超声（US）纵向测量MRD，以研究OA发病和进展过程中的相关特征。
55例膝关节内侧疼痛的患者参与了本研究。其中46例患者能够进行5年的随访，因此根据基线时间点的X线检查，将他们分为32例OA前期患者（女性：59%，平均年龄：69.0岁）和14例早期OA患者（女性：78%，平均年龄：74.4岁）。在基线、1年和5年后，使用超声在站立位和仰卧位测量MRD。分析校正骨骼大小后的MRD，即内侧位移指数（MDI）。根据Kellgren/Lawrence分类，将OA前期和早期OA组在5年后分为亚组：稳定组和OA进展组，并回顾性比较基线、1年和5年时亚组之间的⊿MDI（站立位和仰卧位MDI的差值）。
在整个OA前期组中，仰卧位和站立位的MDI在5年时分别增加了7%和10%，显示出显著增加（P = 0.044，0.0147）。OA前期和早期OA组中OA进展亚组的⊿MDI显著更大（分别为P = 0.02和0.03），并且在OA前期进展组中持续为6 - 7%，表明位移率是稳定组的2倍或更高。
超声测量的⊿MDI增加可能是OA疾病阶段进展的一个重要危险因素，并且可作为预测膝关节X线OA发病的一个特征。
