Lee Sang-June, Kim Jae-Hwa, Baek Eugene, Ryu Han-Seung, Han Donghun, Choi Wonchul
Department of Orthopaedic Surgery, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
Department of Orthopaedic Surgery, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Republic of Korea.
Orthop J Sports Med. 2021 Oct 8;9(10):23259671211035372. doi: 10.1177/23259671211035372. eCollection 2021 Oct.
Few clinical studies have reported the predictors of lateral hinge fracture (LHF) after medial opening-wedge high tibial osteotomy (MOWHTO).
PURPOSE/HYPOTHESIS: The purpose was to compare the incidence of LHF on plain radiographs versus computed tomography (CT) scans and to investigate the factors related to the development of LHF after MOWHTO. We hypothesized that (1) a higher LHF detection rate would be seen on CT scans versus plain radiographs and (2) LHF incidence would be related to opening gap width and hinge position.
Cohort study (diagnosis); Level of evidence, 3.
A total of 97 MOWHTO cases were included. The presence and types of LHF were determined from plain radiographs and CT scans. Radiographic parameters were measured on plain radiographs taken 6 weeks postoperatively. Anterior and posterior opening gap widths, coronal and sagittal osteotomy slopes, and fibular height were calculated from CT scans. The wedge-hinge relationship and the zone of hinge position were assessed, and the patient and radiographic factors related to LHF occurrence were evaluated.
Seventeen LHF cases (20.5%) were detected on plain radiographs, while significantly more (37 cases; 44.6%) were found on CT scans ( = .001). Based on Takeuchi classification, 28 LHF cases were considered type 1, 7 were type 2, and 2 were type 3. Logistic regression analysis revealed that opening gap width (odds ratio, 1.615; 95% confidence interval, 1.232-2.118; = .001) and posterior opening gap width (odds ratio, 3.731; 95% confidence interval, 1.642-4.351; = .008,) differed significantly between patients with versus without LHF. Other patient and radiographic factors were not significantly related to LHF occurrence. Receiver operating characteristic curve analysis identified the opening gap width cutoff values for LHF as 11.0 mm (area under the curve, 0.81; sensitivity, 78.4%; specificity, 73.9%).
The incidence of LHF after MOWHTO can be underestimated on plain radiographs compared with CT scans. Only large opening gap width, especially posterior gap width, was found to have a statistically significant relationship with occurrence of LHF. Therefore, special caution for possible LHF may be needed if a large correction is planned.
很少有临床研究报道内侧开放楔形高位胫骨截骨术（MOWHTO）后外侧铰链骨折（LHF）的预测因素。
目的/假设：目的是比较X线平片与计算机断层扫描（CT）上LHF的发生率，并研究MOWHTO后LHF发生发展的相关因素。我们假设：（1）与X线平片相比，CT扫描上LHF的检出率更高；（2）LHF的发生率与开口间隙宽度和铰链位置有关。
队列研究（诊断）；证据等级，3级。
共纳入97例MOWHTO病例。根据X线平片和CT扫描确定LHF的存在及类型。术后6周拍摄的X线平片上测量影像学参数。从CT扫描中计算前后开口间隙宽度、冠状面和矢状面截骨斜率以及腓骨高度。评估楔形-铰链关系和铰链位置区域，并评估与LHF发生相关的患者和影像学因素。
X线平片上检测到17例LHF病例（20.5%），而CT扫描上发现的病例明显更多（37例；44.6%）（P = 0.001）。根据竹内分类，28例LHF病例为1型，7例为2型，2例为3型。逻辑回归分析显示，有LHF与无LHF的患者之间，开口间隙宽度（优势比，1.615；95%置信区间，1.232 - 2.118；P = 0.001）和后开口间隙宽度（优势比，3.731；95%置信区间，1.642 - 4.351；P = 0.008）有显著差异。其他患者和影像学因素与LHF的发生无显著相关性。受试者工作特征曲线分析确定LHF的开口间隙宽度临界值为11.0 mm（曲线下面积，0.81；灵敏度，78.4%；特异度，73.9%）。
与CT扫描相比，MOWHTO后LHF的发生率在X线平片上可能被低估。仅发现大的开口间隙宽度尤其是后间隙宽度与LHF的发生有统计学显著关系。因此，如果计划进行大的矫正，可能需要特别警惕可能发生的LHF。
