Patel Akshar H, Wilder J Heath, Weldy John M, Ross Bailey J, Kim Nathaniel E, Wang Hao, Sanchez Fernando L, Sherman William F
Department of Orthopaedic Surgery, Tulane University School of Medicine, New Orleans, LA, USA.
Department of Biomedical Engineering, Tulane University School of Science & Engineering, New Orleans, LA, USA.
Arthroplast Today. 2022 Mar 15;14:140-147. doi: 10.1016/j.artd.2022.02.012. eCollection 2022 Apr.
Patellar resurfacing is routinely performed during total knee arthroplasty to reduce pain associated with patellofemoral osteoarthritis. With 3-dimensional ingrowth materials readily available, the present study aimed to evaluate if cemented polyethylene (CP) patellar buttons conferred higher ultimate load to failure than press-fit metal-backed (PF) buttons in axial compression.
Ten matched cadaveric and 20 composite patellae were resurfaced and implanted with either a PF or CP button. Biomechanical testing using an MTS machine was performed to measure the force required to generate a periprosthetic patella fracture. Mean load to failure and load to failure per 1-mm patellar thickness were compared with a paired and independent samples Students' t-test for the cadaveric and composite patellae, respectively.
The average load to failure for the matched cadaveric patellae with PF implants was significantly lower than that for patellae with CP buttons (4082.05 N vs 5898.37 N, = .045). The average load to failure for composite patella with PF implants was significantly higher than that for composite patellae with CP implants (6004.09 N vs 4551.40 N, = .001). The mean load to failure per 1-mm patellar thickness was also significantly higher for composite patellae with PF implants (263.80 N/mm vs 200.37 N/mm, = .001).
Cadaveric patellae with cemented implants had a significantly higher ultimate load to failure in axial compression than press-fit patella. However, this result was reversed in the composite model. Exploration of biological and composite model properties could provide further insight into patellar implant selection during total knee arthroplasty.
在全膝关节置换术中常规进行髌骨表面置换，以减轻与髌股骨关节炎相关的疼痛。随着三维长入材料的 readily available，本研究旨在评估在轴向压缩中，骨水泥固定的聚乙烯（CP）髌骨纽扣是否比压配金属背衬（PF）纽扣具有更高的极限破坏载荷。
对10对匹配的尸体髌骨和20个复合髌骨进行表面置换，并植入PF或CP纽扣。使用MTS机器进行生物力学测试，以测量产生假体周围髌骨骨折所需的力。分别对尸体髌骨和复合髌骨，采用配对和独立样本t检验比较平均破坏载荷和每1毫米髌骨厚度的破坏载荷。
植入PF假体的匹配尸体髌骨的平均破坏载荷显著低于植入CP纽扣的髌骨（4082.05牛对5898.37牛， = 0.045）。植入PF假体的复合髌骨的平均破坏载荷显著高于植入CP假体的复合髌骨（6004.09牛对4551.40牛， = 0.001）。植入PF假体的复合髌骨每1毫米髌骨厚度的平均破坏载荷也显著更高（263.80牛/毫米对200.37牛/毫米， = 0.001）。
植入骨水泥的尸体髌骨在轴向压缩中的极限破坏载荷显著高于压配髌骨。然而，在复合模型中这一结果相反。探索生物和复合模型特性可为全膝关节置换术中髌骨植入物的选择提供进一步的见解。
