Department of Orthopaedic Surgery, Yokohama City University, Japan.
Department of Orthopaedic Surgery, Yokohama City University, Japan.
Knee. 2022 Jun;36:72-79. doi: 10.1016/j.knee.2022.04.011. Epub 2022 May 6.
Spontaneous osteonecrosis of the knee (SONK) causes acute atraumatic knee pain, and meniscus tears may be associated with the pathogenesis of SONK. The purpose of this study was to investigate the relationship of the type of meniscus tear and medial meniscus extrusion with SONK on the medial femoral condyle in patients who underwent surgical treatment with high tibial osteotomy due to severe knee pain.
We enrolled 98 patients with 102 knees who underwent medial opening wedge high tibial osteotomy (OWHTO) under the diagnosis of medial femoral condyle osteonecrosis at our hospital from December 2003 to January 2020. Based on the Koshino classification, cases of SONK were classified as stage 1-4. The relationships of demographic data, X-rays and MRI images, including femorotibial angle (FTA), meniscus tear type, and medial meniscus extrusion (MME), with the stage and volume of SONK were investigated.
Ninety-eight patients (29 males and 69 females), with an average age at surgery of 69.2 ± 9.6 years and Body mass index(BMI) of 61.0 ± 17.6 kg/m. In 102 cases of SONK, 11 knees, 18 knees, 46 knees, and 27 knees were classified as stage 1-4, respectively. The mean SONK volume was 2161.61 µm (range 95.67-7484.68 µm) on preoperative MRI. The preoperative FTA (mean 180.86°, range 172-187°) was not associated with the stage or volume of SONK. Meniscus tears were found in all cases of SONK and consisted of 2 degenerations, 2 horizontal tears, 0 vertical tears, 40 radial tears, 4 complex tears, and 54 medial meniscus posterior root tears (MMPRTs). In addition, 99% (101/102) of knees showed more than 3 mm of meniscus extrusion. Although the meniscus tear type was not associated with SONK stage, there was a high rate of tears that caused disruption of the hoop strain, such as MMPRTs (52.9%) or radial tears (39.2%). MME was significantly related to SONK volume (r = 0.387, p < 0.001).
All patients with SONK had coexisting meniscus tears, most menisci had medial extrusion, and a positive correlation was observed between MME and SONK volume.
膝关节自发性骨坏死（SONK）可导致急性创伤性膝关节疼痛，半月板撕裂可能与 SONK 的发病机制有关。本研究的目的是探讨内侧半月板撕裂类型和内侧半月板突出与内侧股骨髁 SONK 之间的关系，这些患者因严重膝关节疼痛接受了高胫骨截骨术的手术治疗。
我们纳入了 98 例 102 膝患者，这些患者均因内侧股骨髁骨坏死于我院于 2003 年 12 月至 2020 年 1 月接受内侧开放楔形胫骨高位截骨术（OWHTO）治疗。根据 Koshino 分类，SONK 病例分为 1-4 期。研究了人口统计学数据、X 射线和 MRI 图像（包括胫股角（FTA）、半月板撕裂类型和内侧半月板突出（MME））与 SONK 分期和体积的关系。
98 例患者（男 29 例，女 69 例），手术时平均年龄 69.2±9.6 岁，体重指数（BMI）为 61.0±17.6kg/m。在 102 例 SONK 中，分别有 11 例、18 例、46 例和 27 例患者被分类为 1-4 期。术前 MRI 显示的 SONK 平均体积为 2161.61µm（范围为 95.67-7484.68µm）。术前 FTA（平均 180.86°，范围 172-187°）与 SONK 分期或体积无关。所有 SONK 患者均存在半月板撕裂，包括 2 例变性、2 例水平撕裂、0 例垂直撕裂、40 例放射状撕裂、4 例复合撕裂和 54 例内侧半月板后根撕裂（MMPRT）。此外，99%（101/102）的膝关节存在半月板突出超过 3mm。尽管半月板撕裂类型与 SONK 分期无关，但存在破坏箍应变的撕裂，如 MMPRT（52.9%）或放射状撕裂（39.2%）的比例较高。MME 与 SONK 体积呈显著正相关（r=0.387，p<0.001）。
所有 SONK 患者均伴有半月板撕裂，大多数半月板存在内侧突出，MME 与 SONK 体积呈正相关。
