Clinique de Saint-Omer, 71, rue Ambroise-Paré, 62575 Saint-Omer, France.
Orthop Traumatol Surg Res. 2019 Feb;105(1S):S165-S176. doi: 10.1016/j.otsr.2018.05.020. Epub 2019 Jan 8.
Patellofemoral arthroplasty (PFA) has seen its role validated over the last decade as a treatment for severe Iwano III or IV patellofemoral osteoarthritis (PFOA). The ideal indication is PFOA with femoral trochlear dysplasia. The accumulation of data on factors influencing the likelihood of PFA failure or success when using first- or second-generation implants has led to design changes, which have been incorporated into modern third-generation implants. These implants are positioned using anatomic cuts, with instrumentation kits that ensure accurate and reproducible alignment. Their design corrects the femoral trochlear dysplasia. Refinements in the indications of PFA, together with advances in prosthetic kinematics and improved understanding of the surgical technique, have strengthened the role for PFA. Although either a lateral or a medial approach can be used, the lateral approach deserves preference. Proper orientation of the femoral and patellar implants is crucial and can be achieved in an accurate and reproducible manner. Orientation of the coronal femoral cut is the only modifiable variable. The cut should be performed with the knee in neutral rotation to minimise both the tibial tuberosity-trochlear groove distance and the amount of extensor apparatus valgus. In the coronal plane, the femoral component must be positioned in valgus, to align the distal part of the trochlear implant with the lateral condylar cartilage. Medial positioning of the patellar component finalises the match between the femur and the patella. This coronal alignment of the two components promotes patellar engagement at the beginning of knee flexion. Thus, the technique brings the trochlea towards the patella and the patella towards the trochlea, thereby ensuring optimal patellofemoral tracking and ensuring a good final outcome. When these requirements are met, the functional and radiographic outcomes are predictable, of good quality, and sustained over time, provided the patient remains free of tibio-femoral osteoarthritis.
髌股关节成形术（PFA）在过去十年中已被证明可用于治疗严重的 Iwano III 或 IV 髌股关节炎（PFOA）。理想的适应证是伴有股骨滑车发育不良的 PFOA。有关影响第一代或第二代植入物使用时 PFA 失败或成功可能性的因素的数据积累导致了设计的改变，这些改变已被纳入现代第三代植入物中。这些植入物使用解剖切口定位，其器械套件可确保准确和可重复的对准。它们的设计可纠正股骨滑车发育不良。PFA 适应证的细化，以及假体运动学的进步和对手术技术的深入了解，加强了 PFA 的作用。尽管可以使用外侧或内侧入路，但外侧入路更值得推荐。正确定位股骨和髌骨植入物至关重要，并且可以以准确和可重复的方式实现。冠状股骨切口的方向是唯一可调整的变量。应在膝关节中立旋转时进行该切口，以尽量减少胫骨结节-滑车沟距离和伸肌装置外旋的量。在冠状面，股骨部件必须向外旋定位，以使滑车植入物的远端与外侧髁软骨对齐。髌骨组件的内侧定位最终确定了股骨和髌骨之间的匹配。这两个组件的冠状对准可促进膝关节屈曲开始时髌骨的啮合。因此，该技术使滑车朝向髌骨，髌骨朝向滑车，从而确保最佳的髌股关节跟踪，并确保良好的最终结果。当满足这些要求时，功能和影像学结果是可预测的、质量良好的，并且随着时间的推移是可持续的，只要患者没有胫股关节炎。
