Du Yin-Qiao, Shen Jun-Min, Sun Jing-Yang, Xu Chi, Ni Ming, Zhou Yong-Gang
Department of Orthopaedics, General Hospital of Chinese People's Liberation Army, Beijing 100853, People's Republic of China.
Patient Prefer Adherence. 2020 Dec 16;14:2469-2475. doi: 10.2147/PPA.S285545. eCollection 2020.
The study assessed the correlation among the patients' perception of leg length discrepancy (LLD) after total hip arthroplasty (THA) in patients with unilateral Crowe type IV developmental dysplasia of the hip (DDH) and the four methods of measuring the leg length in the full-length standing anteroposterior radiographs.
Sixty patients with unilateral Crowe type IV DDH were recruited in this retrospective study between January 2012 and January 2019. Four methods of measurement were used: 1) TD-TP: distance between the inferior aspect of teardrop (TD) and the midpoint of tibial plafond (TP); 2) CH-TP: distance between the center of the hip (CH) or acetabular cup and the TP; 3) GT-TP: distance between the apex of greater trochanter (GT) and the TP; and 4) FL+TL: the sum of femoral length (FL) and tibial length (TL).
Association was found among the patients' perception on LLD with difference in TD-TP (OR=1.157), and the difference in FL+TL (OR=1.166). The area under the curve of the difference in FL+TL and the difference TD-TP (0.704 and 0.679) was significantly higher than those of the difference in CH-TP and the difference in GT-TP (0.564 and 0.483). With the calculated threshold of LLD set at 9.0 mm, the sensitivity and specificity of the difference in TD-TP and the difference in FL+TL were 57.7%, 79.4% and 61.5%, 79.4%, respectively.
Patients' perception on LLD had good correlation and reliability on the difference of FL+TL and the difference of TD-TP on both sides in the full-length standing anteroposterior radiographs after THA in patients with unilateral Crowe type IV DDH. The calculated threshold of the difference in FL+TL and the difference in TD-TP was set at 9.0 mm to assess the patients' perception on LLD.
本研究评估了单侧Crowe IV型发育性髋关节发育不良（DDH）患者全髋关节置换术（THA）后患者对肢体长度差异（LLD）的感知与全长站立位前后位X线片中四种测量腿长方法之间的相关性。
本回顾性研究纳入了2012年1月至2019年1月期间的60例单侧Crowe IV型DDH患者。使用了四种测量方法：1）TD-TP：泪滴下缘（TD）与胫骨平台中点（TP）之间的距离；2）CH-TP：髋关节中心（CH）或髋臼杯与TP之间的距离；3）GT-TP：大转子尖（GT）与TP之间的距离；4）FL+TL：股骨长度（FL）与胫骨长度（TL）之和。
发现患者对LLD的感知与TD-TP差异（OR=1.157）以及FL+TL差异（OR=1.166）之间存在关联。FL+TL差异和TD-TP差异的曲线下面积（分别为0.704和0.679）显著高于CH-TP差异和GT-TP差异的曲线下面积（分别为0.564和0.483）。将计算出的LLD阈值设定为9.0 mm时，TD-TP差异和FL+TL差异的敏感性和特异性分别为57.7%、79.4%和61.5%、79.4%。
在单侧Crowe IV型DDH患者THA后的全长站立位前后位X线片中，患者对LLD的感知与两侧FL+TL差异和TD-TP差异具有良好的相关性和可靠性。将FL+TL差异和TD-TP差异的计算阈值设定为9.0 mm以评估患者对LLD的感知。
