Hughes Andrew J, Neitzke Colin C, O'Donnell Jeffrey A, Chiu Yu-Fen, Gausden Elizabeth B, Lee Gwo-Chin, Sculco Peter K, Chalmers Brian P
Department of Orthopedic Surgery, Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, New York; Hospital for Special Surgery, Stavros Niarchos Foundation Complex Joint Reconstruction Center, New York, New York; National Orthopaedic Hospital Cappagh, Dublin, Ireland.
Department of Orthopedic Surgery, Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, New York.
J Arthroplasty. 2025 Sep;40(9S1):S470-S480.e1. doi: 10.1016/j.arth.2025.05.002. Epub 2025 May 9.
Distal femoral replacement (DFR) is a salvage option for massive femoral bone loss and is often performed in revision total knee arthroplasty (rTKA) that have undergone multiple prior procedures. This study aimed to report on a large cohort of DFRs performed at a tertiary referral institution regarding survivorship and risk factors for aseptic loosening, specifically the impact of a previously instrumented femoral canal.
Between 2016 and 2021, 105 patients undergoing rTKA to DFR with a minimum 2-year follow-up were identified. Kaplan-Meier estimates assessed survivorship free from all-cause reoperation, all-cause revision, and revision for aseptic loosening. Logistic regressions were conducted to assess potential risk factors for radiographic loosening and the need for revision.
Prior femoral canal instrumentation was identified in 59% of cases, and 54% had undergone multiple prior procedures. The 2-year survivorship free from revision for aseptic loosening was 93%. The 2-year survivorship free from all-cause reoperation was 87% for native canals and 59% for previously instrumented canals (P = 0.008). The 2-year survivorship free from all-cause revision was 100 and 81%, respectively (P = 0.014). Regression analysis found re-rTKA (odds ratio [OR] = 18.3, P = 0.006), prior femoral canal instrumentation (OR = 14.6, P = 0.01), and prior femoral canal cementation (OR = 8.2, P = 0.007) to be risk factors for aseptic loosening.
A DFR for rTKA had high 2-year survivorship free from revision for aseptic loosening (93%). Regression analyses revealed multiple risk factors for aseptic femoral component loosening with a previously instrumented femoral canal, resulting in a 2.8-times higher rate of reoperation, a 10.5-times higher rate of all-cause revision, and an 11-times higher rate of aseptic loosening. Future research on fixation strategies in sclerotic, previously instrumented femoral canals should be prioritized to reduce the risk of fixation failure in this high-risk cohort.
股骨远端置换术（DFR）是治疗大面积股骨骨丢失的一种挽救性选择，常用于多次翻修全膝关节置换术（rTKA）。本研究旨在报告一家三级转诊机构进行的大量DFR病例的生存率以及无菌性松动的危险因素，特别是既往股骨骨髓腔已使用器械操作的影响。
在2016年至2021年期间，确定了105例行rTKA并接受DFR且至少随访2年的患者。采用Kaplan-Meier法评估无全因再次手术、全因翻修以及无菌性松动翻修的生存率。进行逻辑回归分析以评估影像学松动和翻修需求的潜在危险因素。
59%的病例存在既往股骨骨髓腔器械操作，54%的患者接受过多次既往手术。无菌性松动翻修的2年生存率为93%。原生骨髓腔无全因再次手术的2年生存率为87%，既往使用器械操作的骨髓腔为59%（P = 0.008）。无全因翻修的2年生存率分别为100%和81%（P = 0.014）。回归分析发现再次rTKA（比值比[OR]=18.3，P = 0.006）、既往股骨骨髓腔器械操作（OR = 14.6，P = 0.01）以及既往股骨骨髓腔骨水泥固定（OR = 8.2，P = 0.007）是无菌性松动的危险因素。
rTKA行DFR术后无菌性松动翻修的2年生存率较高（93%）。回归分析揭示了既往使用器械操作的股骨骨髓腔无菌性股骨假体松动的多个危险因素，导致再次手术率高出2.8倍，全因翻修率高出10.5倍，无菌性松动率高出11倍。未来应优先研究硬化的、既往使用器械操作的股骨骨髓腔的固定策略，以降低这一高危人群的固定失败风险。
