Bauer Leandra, Woiczinski Matthias, Thorwächter Christoph, Melsheimer Oliver, Weber Patrick, Grupp Thomas M, Jansson Volkmar, Steinbrück Arnd
Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital, LMU Munich, Marchioninistraße 15, 81377 Munich, Germany.
German Arthroplasty Registry (EPRD Deutsche Endoprothesenregister gGmbH), Straße des 17. Juni 106-108, 10623 Berlin, Germany.
J Clin Med. 2021 Mar 16;10(6):1227. doi: 10.3390/jcm10061227.
The German Arthroplasty registry (EPRD) has shown that different prosthesis systems have different rates of secondary patellar resurfacing: four years after implantation, the posterior-stabilized (PS) Vega prosthesis has a 3.2% risk of secondary patellar resurfacing compared to the cruciate-retaining (CR) Columbus prosthesis at 1.0% (both Aesculap AG, Tuttlingen, Germany). We hypothesized that PS implants have increased retropatellar pressure and a decreased retropatellar contact area compared to a CR design, which may lead to an increased likelihood of secondary patellar resurfacing. Eight fresh frozen specimens (cohort 1) were tested with an established knee rig. In addition, a possible influence of the registry-based patient collective (cohort 2) was investigated. No significant differences were found in patient data-cohort 2-(sex, age). A generally lower number of PS system cases is noteworthy. No significant increased patella pressure could be detected with the PS design, but a lower contact area was observed (cohort 1). Lower quadriceps force (100°-130° flexion), increased anterior movement of the tibia (rollback), greater external tilt of the patella, and increasing facet pressure in the Vega PS design indicate a multifactorial cause for a higher rate of secondary resurfacing which was found in the EPRD patient cohort and might be related to the PS' principle function.
德国关节成形术登记处（EPRD）的数据显示，不同的假体系统二次髌骨表面置换率不同：植入四年后，后稳定型（PS）Vega假体二次髌骨表面置换的风险为3.2%，而保留交叉韧带型（CR）Columbus假体为1.0%（两者均来自德国图特林根的蛇牌股份公司）。我们推测，与CR设计相比，PS植入物会增加髌后压力并减小髌后接触面积，这可能会导致二次髌骨表面置换的可能性增加。使用一台成熟的膝关节试验装置对8个新鲜冷冻标本（队列1）进行了测试。此外，还研究了基于登记处患者群体（队列2）的可能影响。在患者数据（队列2）中未发现显著差异（性别、年龄）。值得注意的是，PS系统病例数量总体较少。在PS设计中未检测到显著增加的髌骨压力，但观察到接触面积较小（队列1）。较低的股四头肌力量（屈曲100°-130°时）、胫骨向前运动增加（后滚）、髌骨更大的向外倾斜以及Vega PS设计中关节面压力增加，表明了EPRD患者队列中二次表面置换率较高的多因素原因，这可能与PS的主要功能有关。
