Colyn William, Neirynck J, Vanlommel E, Bruckers L, Bellemans J
Department of Orthopaedic Surgery, AZ Turnhout, Rubenstraat 166, Turnhout, Belgium.
Faculty of Medicine and Life Sciences, UHasselt, Hasselt University, 3590, Diepenbeek, Belgium.
Arch Orthop Trauma Surg. 2023 Mar;143(3):1593-1598. doi: 10.1007/s00402-022-04447-9. Epub 2022 Apr 29.
High-grade varus osteoarthrosis (OA) is characterized by a pronounced intra-articular varus deformity and associated insufficiency of the lateral ligamentous complex. When performing a total knee arthroplasty (TKA) in such a knee, traditionally the alignment is restored to neutral, and the medial soft tissue structures are released to compensate for the lateral laxity and balance the joint. However, another option would be to leave the medial soft tissues untouched and accept the lateral laxity but to compensate for it using an ML-stabilized constrained-condylar knee (CCK) design. Our aim was to prove our hypothesis that such knees would demonstrate better clinical stability and better functionality as well as subjective outcome scores.
We searched our bicenter database of 912 primary TKAs (from 2016 to 2019) for primary TKA patients with a preoperative varus alignment of > 8°. After inclusion, 60 patients were divided into three groups by implant design: CCK (n = 21), posterior-stabilized (PS) (n = 20) and cruciate-retaining (CR) (n = 19). Oxford Knee Score (OKS), Forgotten Joint Score (FJS), Knee Society Score (KSS), UCLA-activity score, ML instability scores and both radiographic and clinical data were compared between groups.
ML stability was significantly better in CCK designs (86% grade 0) compared to CR (37% grade 0) (p = 0.004) but not PS (70% grade 0) designs. No grade II instability was present in CCK and PS implants compared to 16% of CR implants. KSS and UCLA-activity score were higher in CCK designs compared to PS (p = 0.027, p = 0.041) and CR designs (p < 0.001, p = 0.007). OKS and FJS were higher in CCK designs compared to CR (p = 0.025, p = 0.008) but not to PS.
The use of a CCK design to compensate for the lateral laxity in high-grade varus OA knees allowed to refrain from a medial release. CCK designs displayed improved clinical stability and better functionality as well as subjective outcome scores compared to less-constrained designs.
重度内翻型骨关节炎（OA）的特征是关节内明显的内翻畸形以及外侧韧带复合体相关的功能不全。在这样的膝关节进行全膝关节置换术（TKA）时，传统上会将力线恢复至中立位，并松解内侧软组织结构以补偿外侧松弛并平衡关节。然而，另一种选择是不触动内侧软组织，接受外侧松弛，但使用内侧稳定型限制性髁型膝关节（CCK）设计来进行补偿。我们的目的是验证我们的假设，即这类膝关节将表现出更好的临床稳定性、更好的功能以及主观结果评分。
我们在我们包含912例初次TKA（2016年至2019年）的双中心数据库中，搜索术前内翻力线>8°的初次TKA患者。纳入后，60例患者根据植入物设计分为三组：CCK组（n = 21）、后稳定型（PS）组（n = 20）和保留交叉韧带型（CR）组（n = 19）。比较了三组之间的牛津膝关节评分（OKS）、遗忘关节评分（FJS）、膝关节协会评分（KSS）、加州大学洛杉矶分校活动评分、内侧-外侧不稳定评分以及影像学和临床数据。
与CR组（0级占37%）相比，CCK设计的内侧-外侧稳定性明显更好（0级占86%）（p = 0.004），但与PS组（0级占70%）相比无差异。与16%的CR植入物相比，CCK和PS植入物中不存在II级不稳定情况。与PS组（p = 0.027，p = 0.041）和CR组（p < 0.001，p = 0.007）相比，CCK设计的KSS和加州大学洛杉矶分校活动评分更高。与CR组相比，CCK设计的OKS和FJS更高（p = 0.025，p = 0.008），但与PS组相比无差异。
在重度内翻型OA膝关节中使用CCK设计来补偿外侧松弛，无需进行内侧松解。与限制性较小的设计相比，CCK设计表现出更好的临床稳定性、更好的功能以及主观结果评分。
