University Center of Orthopaedic, Trauma and Plastic Surgery, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany.
Knee Surg Sports Traumatol Arthrosc. 2022 Sep;30(9):3000-3006. doi: 10.1007/s00167-021-06545-4. Epub 2021 Apr 11.
If substitution of the posterior cruciate ligament in total knee arthroplasty is necessary, there are two options available: posterior stabilized (PS) design with a post-cam mechanism or anterior-lipped ultracongruent (UC) inserts. UC inserts have the advantage that no femoral box is necessary and a standard femoral component can be used. The aim of this study was to compare the range of motion (ROM) and patient-reported outcome (PRO) after UC and PS fixed-bearing TKA. Better ROM in PS TKA and no difference in PRO between both designs was hypothesized.
A randomized controlled trial with 127 patients receiving a fixed-bearing UC or PS design of the same knee system was performed. Nine patients died and there were four revision surgeries. 107 patients completed the 5-year follow-up. Patient-reported outcome was assessed. Patellofemoral problems were evaluated using selected applicable questions of the Oxford Knee Score (getting up from a table, kneeling, climbing stairs).
Surgical time was 10 min shorter in the UC group (p < 0.001). After 5 years, both groups demonstrated good knee function and health-related quality of life without significant differences between the groups. Both groups demonstrated a high satisfaction score and the majority of patients would undergo this surgery again. Patellofemoral problems were recognized more frequently in the PS group (p = 0.025).
Both designs demonstrated similar good results after 5 years. Stabilization with an anterior-lipped UC insert can be considered a safe alternative to the well-established PS design if cruciate substitution is necessary.
如果全膝关节置换术需要替代后交叉韧带，有两种选择：带后凸轮机构的后稳定（PS）设计或前唇超配（UC）衬垫。UC 衬垫的优点是不需要股骨盒，并且可以使用标准的股骨部件。本研究的目的是比较 UC 和 PS 固定轴承 TKA 后的活动范围（ROM）和患者报告的结果（PRO）。假设 PS TKA 的 ROM 更好，两种设计的 PRO 没有差异。
对 127 例接受相同膝关节系统固定轴承 UC 或 PS 设计的患者进行了随机对照试验。9 例患者死亡，4 例进行了翻修手术。107 例患者完成了 5 年随访。评估了患者报告的结果。髌股关节问题使用牛津膝关节评分（从桌子上站起来、跪地、爬楼梯）的选定适用问题进行评估。
UC 组的手术时间缩短了 10 分钟（p<0.001）。5 年后，两组均表现出良好的膝关节功能和健康相关生活质量，组间无显著差异。两组的满意度评分均较高，大多数患者会再次接受这种手术。PS 组髌股关节问题更为常见（p=0.025）。
两种设计在 5 年后均显示出相似的良好结果。如果需要替代交叉韧带，带前唇 UC 衬垫的稳定可以被认为是一种替代后稳定设计的安全选择。
