Zielinski Matthew R, Deckard Evan R, Meneghini R Michael
Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
IU Health Hip & Knee Center, IU Health Saxony Hospital, Fishers, IN, USA.
Arthroplast Today. 2021 Mar 7;8:96-102. doi: 10.1016/j.artd.2021.01.018. eCollection 2021 Apr.
The enhanced frictional resistance of modern ultraporous acetabular components can impede complete seating; however, surgeons expect the enhanced ingrowth surface to resolve polar (zone 2) gaps over time via osseointegration. This study characterized zone 2 radiographic osseointegration in 3 acetabular component designs: 2 highly porous ingrowth and one traditional ongrowth.
A consecutive cohort of primary total hip arthroplasties was reviewed which utilized 3 different acetabular cup designs: ongrowth titanium with hydroxyapatite (HA), highly porous titanium with machined radial grooves (MRG), and dual-porous titanium substrate with micropore (MP). Radiographic analysis was performed using accepted measurement criteria with particular attention to radiolucent lines.
Seven hundred ninety cases were available for analysis. Initial 1-month radiographs revealed 43.2% of HA, 78.2% of MRG, and 81.0% of MP cups exhibited zone 2 radiolucencies, consistent with incomplete seating. At 1 year, all HA radiolucencies resolved, whereas 46.2% and 34.7% of radiolucencies remained in MRG and MP cups, respectively ( ≤ .005). At minimum 2 years, a significant proportion of zone 2 radiolucencies remained in 46.0% of MRG compared with 23.9% of MP cups and 3.0% of HA cups ( ≤ .007).
The resolution of zone 2 radiolucencies at 1-year and minimum 2-year follow-up signified osseointegration for nearly all HA and most MP cups. Highly porous titanium cups with machined radial grooves demonstrated persistent zone 2 radiolucencies at 1 year and beyond. Given reports of early loosening with this particular acetabular implant, further follow-up is warranted as this study highlights that not all contemporary highly porous metal acetabular components perform equally.
III.
现代超多孔髋臼组件增强的摩擦阻力可能会阻碍完全就位；然而，外科医生期望增强的骨长入表面能随着时间推移通过骨整合解决极地（2区）间隙问题。本研究对三种髋臼组件设计的2区影像学骨整合情况进行了特征描述：两种高度多孔的骨长入型和一种传统的骨附着型。
回顾了一组连续的初次全髋关节置换病例，这些病例使用了三种不同的髋臼杯设计：带羟基磷灰石（HA）的骨附着型钛杯、带加工径向凹槽（MRG）的高度多孔钛杯和带微孔（MP）的双多孔钛基板杯。使用公认的测量标准进行影像学分析，特别关注透光线。
共有790例可供分析。最初的1个月X线片显示，43.2%的HA杯、78.2%的MRG杯和81.0%的MP杯出现2区透光线，这与不完全就位一致。1年时，所有HA杯的透光线均消失，而MRG杯和MP杯分别有46.2%和34.7%的透光线仍存在（P≤.005）。至少2年时，MRG杯中有46.0%的2区透光线仍显著存在，而MP杯为23.9%，HA杯为3.0%（P≤.007）。
在1年和至少2年的随访中，2区透光线消失表明几乎所有HA杯和大多数MP杯实现了骨整合。带加工径向凹槽的高度多孔钛杯在1年及以后仍存在持续的2区透光线。鉴于有报道称这种特定的髋臼植入物早期会松动，鉴于本研究强调并非所有当代高度多孔金属髋臼组件的表现都相同，因此有必要进行进一步随访。
III级。
