Lakstein Dror, Tan Zachary, Oren Nugzar, Mäkinen Tatu Johannes, Gross Allan E, Safir Oleg
Orthopedic department, E. Wolfson medical center, Holon - Israel.
Sackler faculty of Medicine, Tel-Aviv University, Tel-Aviv - Israel.
Hip Int. 2017 Feb 21;27(1):55-59. doi: 10.5301/hipint.5000419. Epub 2016 Oct 24.
When performing total hip arthroplasty (THA) on a dysplastic hip, proper positioning of the acetabular component may not allow for more than 70% coverage. Structural support in the form of an autograft or a high porosity metal augment may be necessary. The purpose of the study was to investigate the value of preoperative templating and deformity classification in predicting cup coverage and the need for structural support.
65 cases of THA for DDH were retrospectively analysed. 2 observers independently classified each dysplastic hip according to Hartofilakidis and determined the extent of cup coverage via templating software on preoperative digital AP pelvic radiographs.
Weighted kappa interobserver agreement was 0.68 for cup coverage and 0.76 for Hartofilakidis type. Structural support was necessary in 10 hips. No structural support was necessary in Hartofilakidis type 1, dysplasia cases. However, 27-30% of cases with type 2 or type 3 dysplasia required structural support. All cases with templated cup coverage of 65% or less required structural support. Templated coverage within 65-75% and over 75% resulted in 20% and 10% of patients receiving structural augmentation, respectively.
Preoperative planning for THA in the setting of hip dysplasia is crucial and can provide valuable insight to the need for column augmentation. However, the 3-D severity of the deformity may be underestimated in the 2-D radiographs.
在发育不良的髋关节上进行全髋关节置换术（THA）时，髋臼组件的正确定位可能无法实现超过70%的覆盖。可能需要自体骨移植或高孔隙率金属增强物形式的结构支撑。本研究的目的是调查术前模板测量和畸形分类在预测髋臼覆盖范围和结构支撑需求方面的价值。
回顾性分析65例发育性髋关节发育不良（DDH）患者行THA的病例。2名观察者根据Hartofilakidis方法独立对每个发育不良的髋关节进行分类，并通过术前数字化骨盆前后位X线片上的模板测量软件确定髋臼覆盖范围。
观察者间关于髋臼覆盖范围的加权kappa一致性为0.68，关于Hartofilakidis类型的一致性为0.76。10例髋关节需要结构支撑。Hartofilakidis 1型发育不良病例无需结构支撑。然而，2型或3型发育不良病例中有27%-30%需要结构支撑。所有模板测量髋臼覆盖范围为65%或更低的病例均需要结构支撑。模板测量覆盖范围在65%-75%和超过75%时，分别有20%和10%的患者接受了结构增强。
髋关节发育不良情况下THA的术前规划至关重要，可为柱增强的需求提供有价值的见解。然而，二维X线片可能低估畸形的三维严重程度。
