Bauer Leandra, Thorwächter Christoph, Steinbrück Arnd, Jansson Volkmar, Traxler Hannes, Alic Zumreta, Holzapfel Boris Michael, Woiczinski Matthias
Department of Orthopaedics and Trauma Surgery, Musculoskeletal University Center Munich (MUM), University Hospital, LMU Munich, Marchioninistraße 15, 81377 Munich, Germany.
Orthopaedic Surgical Competence Center Augsburg (OCKA), Vinzenz-von-Paul-Platz 1, 86152 Augsburg, Germany.
J Clin Med. 2022 Nov 21;11(22):6875. doi: 10.3390/jcm11226875.
During total knee arthroplasty (TKA), one of the key alignment factors to pay attention to is the posterior tibial slope (PTS). The PTS clearly influences the kinematics of the knee joint but must be adapted to the coupling degree of the specific TKA design. So far, there is hardly any literature including clear recommendations for how surgeons should choose the PTS in a medial stabilized (MS) TKA. The aim of the present study is to investigate the effects of different degrees of PTS on femorotibial kinematics in MS TKA.
An MS TKA was performed in seven fresh-frozen human specimens successively with 0°, 3°, and 6° of PTS. After each modification, weight-bearing deep knee flexion (30-130°) was performed, and femorotibial kinematics were analyzed.
A lateral femoral rollback was observed for all three PTS modifications. With an increasing PTS, the tibia was shifted more anteriorly on the lateral side (0° PTS anterior tibial translation -9.09 (±9.19) mm, 3° PTS anterior tibial translation -11.03 (±6.72) mm, 6° PTS anterior tibial translation 11.86 (±9.35) mm). No difference in the tibial rotation was found for the different PTS variants. All PTS variants resulted in internal rotation of the tibia during flexion. With a 3° PTS, the design-specific medial rotation point was achieved more accurately.
According to our findings, we recommend a PTS of 3° when implanting the MS prosthesis used in this study.
在全膝关节置换术（TKA）中，需要关注的关键对线因素之一是胫骨后倾坡度（PTS）。PTS明显影响膝关节的运动学，但必须与特定TKA设计的耦合程度相适应。到目前为止，几乎没有文献就外科医生在使用内侧稳定型（MS）TKA时应如何选择PTS给出明确建议。本研究的目的是探讨不同程度的PTS对MS TKA中股骨胫骨运动学的影响。
对7个新鲜冷冻人体标本依次进行PTS为0°、3°和6°的MS TKA手术。每次调整后，进行负重下的深度屈膝（30°-130°），并分析股骨胫骨运动学。
所有三种PTS调整均观察到股骨外侧后滚。随着PTS增加，胫骨在外侧向前移位更多（0°PTS时胫骨前移-9.09（±9.19）mm，3°PTS时胫骨前移-11.03（±6.72）mm，6°PTS时胫骨前移11.86（±9.35）mm）。不同PTS变体的胫骨旋转无差异。所有PTS变体在屈膝时均导致胫骨内旋。采用3°PTS时，能更准确地达到设计特定的内侧旋转点。
根据我们的研究结果，我们建议在植入本研究中使用的MS假体时，PTS为3°。
