Department of Orthopaedic Surgery, University of California Los Angeles Medical Center, 1250 16th Street Room 745, Santa Monica, CA 90404, USA.
Clin Orthop Relat Res. 2010 Aug;468(8):2198-210. doi: 10.1007/s11999-009-1197-8. Epub 2009 Dec 22.
Advocates of newer implant designs cite high rates of aseptic loosening and failure as reasons to abandon traditional cemented endoprosthetic reconstruction of the distal femur.
QUESTIONS/PURPOSES: We asked whether newer, modular distal femoral components had improved survivorship compared with older, custom-casted designs.
We retrospectively reviewed 254 patients who underwent distal femoral endoprosthetic reconstruction. We excluded two patients with cementless implants, 27 with expandable prostheses, and 39 who had a nontumor diagnosis. This left 186 patients: 101 with older custom implants and 85 with contemporary modular implants. The minimum followup was 1 month (mean, 96.0 months; range, 1-336 months). The tumor was classified as Stage IIA/IIB in 122 patients, Stage IA/IB or benign in 43, and Stage III or metastatic in 21.
Kaplan-Meier analysis revealed overall 10-, 20-, and 25-year implant survival rates of 77%, 58%, and 50%, respectively, using revision of the stemmed components as an end point. The 85 modular components had a greater 15-year survivorship than the 101 custom-designed implants: 93.7% versus 51.7%, respectively. Thirty-five stemmed components (18.8%) were revised for aseptic loosening in 22 patients, implant fatigue fracture in 10, infection in two, and local recurrence in one.
Cemented modular rotating-hinge distal femoral endoprostheses demonstrated improved survivorship compared with custom-casted implants during this three-decade experience. Patients with low-grade disease and long-term survivors of high-grade localized disease should expect at least one or more revision procedures in their lifetime.
Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
新设计的植入物的拥护者引用了高比例的无菌性松动和失败，作为放弃传统的股骨远端骨水泥型假体重建的原因。
问题/目的：我们想知道新型模块化股骨远端组件是否比老式定制设计具有更好的生存率。
我们回顾性分析了 254 例股骨远端假体重建患者。我们排除了 2 例非骨水泥植入物患者、27 例可扩张假体患者和 39 例非肿瘤诊断患者。这剩下 186 例患者：101 例使用老式定制植入物，85 例使用现代模块化植入物。随访时间至少为 1 个月（平均 96.0 个月；范围 1-336 个月）。肿瘤分期为ⅡA/ⅡB 期 122 例，ⅠA/ⅠB 期或良性 43 例，Ⅲ期或转移性 21 例。
Kaplan-Meier 分析显示，以翻修股骨柄为终点，整体 10 年、20 年和 25 年的植入物生存率分别为 77%、58%和 50%。85 个模块化组件的 15 年生存率高于 101 个定制设计的植入物：93.7%对 51.7%。22 例患者中有 35 个股骨柄（18.8%）因无菌性松动而翻修，10 例因假体疲劳性骨折，2 例因感染，1 例因局部复发而翻修。
在这项 30 年的经验中，骨水泥型旋转铰链模块化股骨远端假体与定制植入物相比，生存率得到了提高。患有低度疾病的患者和患有高度局限性疾病的长期幸存者，在他们的一生中至少需要进行一次或多次翻修手术。
IV 级，治疗性研究。欲了解完整的证据水平描述，请参见作者指南。
