Department of Orthopedic Surgery, Asklepios Klinikum Bad Abbach, Regensburg University Medical Center, Kaiser-Karl V.-Allee 3, 93077, Bad Abbach, Germany.
Center for Clinical Studies, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93053, Regensburg, Germany.
Arch Orthop Trauma Surg. 2024 Jan;144(1):451-458. doi: 10.1007/s00402-023-05006-6. Epub 2023 Aug 14.
Femoral stem subsidence can lead to aseptic loosening after total hip arthroplasty (THA). Low bone mineral density (BMD) is a risk factor for stem subsidence as it can affect the initial stability and osteointegration. We evaluated whether reduced bone mineral density is related to higher subsidence of the femoral stem after primary cementless THA with enhanced recovery rehabilitation.
79 patients who had undergone primary cementless THA with enhanced recovery rehabilitation were analyzed retrospectively. Subsidence of the femoral stem was measured on standing pelvic anterior-posterior radiographs after 4-6 weeks and one year. Patient individual risk factors for stem subsidence (stem size, canal flare index, canal fill ratio, body mass index (BMI), demographic data) were correlated. Dual X-ray absorptiometry (DXA) scans were performed of the formal neck and the lumbar spine including the calculation of T-score and Z-score. Patient-reported outcome measures were evaluated 12 months postoperatively.
Stem subsidence appeared regardless of BMD (overall collective 2.3 ± 1.64 mm). Measure of subsidence was even higher in patients with normal BMD (2.8 ± 1.7 mm vs. 2.0 ± 1.5 mm, p = 0.05). High BMI was correlated with increased stem subsidence (p = 0.015). Subsidence had no impact on improvement of patient-related outcome measures (WOMAC, EQ-5D-5L and EQ-VAS) after THA. Patients with low BMD reported lower quality of life 12 month postoperatively compared to patients with normal BMD (EQ-5D-5L 0.82 vs. 0.91, p = 0.03).
Stable fixation of a cementless stem succeeds also in patients with reduced BMD. Regarding stem subsidence, enhanced recovery rehabilitation can be safely applied in patients with low BMD.
全髋关节置换术后（THA）股骨柄沉降可导致无菌性松动。低骨密度（BMD）是股骨柄沉降的一个危险因素，因为它会影响初始稳定性和骨整合。我们评估了在接受增强康复康复的初次非骨水泥 THA 后，低骨密度是否与股骨柄更高的沉降有关。
回顾性分析了 79 例接受增强康复康复的初次非骨水泥 THA 的患者。在 4-6 周和 1 年后，通过站立骨盆前后位 X 线片测量股骨柄的沉降。将患者个体股骨柄沉降的危险因素（柄大小、管扩张指数、管填充比、体重指数（BMI）、人口统计学数据）进行相关性分析。对正式颈部和腰椎进行双能 X 线吸收法（DXA）扫描，包括 T 评分和 Z 评分的计算。术后 12 个月评估患者报告的结果测量。
无论 BMD 如何（总体 2.3±1.64mm），股骨柄沉降均出现。BMD 正常的患者沉降测量值更高（2.8±1.7mm 比 2.0±1.5mm，p=0.05）。高 BMI 与股骨柄沉降增加相关（p=0.015）。THA 后，股骨柄沉降对患者相关结果测量（WOMAC、EQ-5D-5L 和 EQ-VAS）的改善没有影响。与 BMD 正常的患者相比，低 BMD 患者术后 12 个月的生活质量报告较低（EQ-5D-5L 0.82 比 0.91，p=0.03）。
即使在低 BMD 的患者中，非骨水泥柄的稳定固定也能成功。关于股骨柄沉降，增强康复康复可安全应用于低 BMD 患者。
