Department of Surgery, Orthopaedic Service, Memorial Sloan Kettering Cancer Center, New York, New York, USA.
Division Chief of Orthopaedic Oncology, Johns Hopkins University, Baltimore, Maryland, USA.
Bone Joint J. 2021 Aug;103-B(8):1405-1413. doi: 10.1302/0301-620X.103B8.BJJ-2020-2323.R1.
Rotating-hinge knee prostheses are commonly used to reconstruct the distal femur after resection of a tumour, despite the projected long-term burden of reoperation due to complications. Few studies have examined the factors that influence their failure and none, to our knowledge, have used competing risk models to do so. The purpose of this study was to determine the risk factors for failure of a rotating-hinge knee distal femoral arthroplasty using the Fine-Gray competing risk model.
We retrospectively reviewed 209 consecutive patients who, between 1991 and 2016, had undergone resection of the distal femur for tumour and reconstruction using a rotating-hinge knee prosthesis. The study endpoint was failure of the prosthesis, defined as removal of the femoral component, the tibial component, or the bone-implant fixation; major revision (exchange of the femoral component, tibial component, or the bone-implant fixation); or amputation.
Multivariate Fine-Gray regression analyses revealed different hazards for each Henderson failure mode: percentage of femoral resection (p = 0.001) and extent of quadriceps muscle resection (p = 0.005) for overall prosthetic failure; extent of quadriceps muscle resection (p = 0.002) and fixation of femoral component (p = 0.011) for type 2 failure (aseptic loosening); age (p = 0.009) and percentage of femoral resection (p = 0.019) for type 3 failure (mechanical failure); and type of joint resection (p = 0.037) for type 4 (infection) were independent predictors. A bone stem ratio of > 2.5 reliably predicted aseptic loosening.
We identified independent risk factors for overall and cause-specific prosthetic failure after rotating-hinge knee distal femoral arthroplasty using a competing risk Fine-Gray model. A bone stem ratio > 2.5 reliably predicts aseptic loosening. An accurate knowledge of the risks of distal femoral arthroplasty after resection for tumour assists surgical planning and managing patient expectations. Cite this article: 2021;103-B(8):1405-1413.
旋转铰链膝关节假体常用于肿瘤切除后重建股骨远端，但由于并发症，预计长期存在再手术的负担。很少有研究检查影响其失败的因素，据我们所知，也没有使用竞争风险模型来研究这些因素。本研究的目的是使用 Fine-Gray 竞争风险模型确定旋转铰链膝关节股骨远端置换术失败的危险因素。
我们回顾性分析了 1991 年至 2016 年间 209 例连续接受旋转铰链膝关节假体切除肿瘤和重建的患者。研究终点为假体失败，定义为股骨组件、胫骨组件或骨-植入物固定物的移除；主要翻修（股骨组件、胫骨组件或骨-植入物固定物的更换）；或截肢。
多变量 Fine-Gray 回归分析显示，每种 Henderson 失效模式的风险不同：股骨切除百分比（p = 0.001）和股四头肌切除程度（p = 0.005）与整体假体失效相关；股四头肌切除程度（p = 0.002）和股骨组件固定（p = 0.011）与 2 型失效（无菌性松动）相关；年龄（p = 0.009）和股骨切除百分比（p = 0.019）与 3 型失效（机械失效）相关；关节切除类型（p = 0.037）与 4 型（感染）相关。骨干比>2.5 可靠地预测无菌性松动。
我们使用竞争风险 Fine-Gray 模型确定了旋转铰链膝关节股骨远端置换术后总体和特定原因假体失败的独立危险因素。骨干比>2.5 可靠地预测无菌性松动。准确了解肿瘤切除后股骨远端置换术的风险有助于手术规划和管理患者的期望。引用本文：2021;103-B(8):1405-1413.
