Department of Surgical Sciences/Section of Orthopedics, Uppsala University.
Department of Orthopedics, Gävle Hospital.
Acta Orthop. 2022 Sep 7;93:709-720. doi: 10.2340/17453674.2022.4537.
Uncemented total hip arthroplasty (THA) is associated with periprosthetic bone loss. In a secondary outcome analysis from a randomized controlled trial, we studied whether denosumab can prevent loss of acetabular periprosthetic bone mineral density (pBMD) in patients who received a trabecular metal cup during uncemented THA.
64 patients (aged 35-65 years) with unilateral osteoarthritis of the hip were randomized to 2 subcutaneous injections with denosumab or placebo, given 1-3 days post-surgery and 6 months post-surgery. Acetabular pBMD was measured in 5 regions of interest (ROIs) by dual-energy X-ray absorptiometry. Serum markers for bone metabolism were analyzed. Periprosthetic osteoblastic activity, measured as standardized uptake values (SUVs) by [18F] positron emission tomography/computed tomography, was evaluated in 32 of the 64 study patients.
After 12 months, patients treated with denosumab had higher pBMD compared with the placebo-treated patients in 4 of 5 ROIs and in sum of ROIs 1-5. After 24 months, the effect on pBMD for patients treated with denosumab declined. Serum markers declined pronouncedly up to 12 months in patients treated with denosumab, but rebounded above baseline levels after 24 months. Patients treated with denosumab had statistically significantly lower SUVs in all ROIs, except ROI 5, after 6 months.
Based on this exploratory analysis of secondary endpoints the application of denosumab seems associated with preserved acetabular pBMD, reduced bone metabolism and attenuated periprosthetic osteoblastic activity. However, given the known rebound affects after discontinuation of denosumab treatment, these effects cannot be expected to persist. If prolonged treatment or shift to other regimes would be beneficial to reduce the risk of cup loosening is yet to be investigated.
非骨水泥全髋关节置换术（THA）与假体周围骨丢失有关。在一项随机对照试验的次要结局分析中，我们研究了在接受非骨水泥 THA 时使用多孔金属杯的患者中，地舒单抗是否可以预防髋臼假体周围骨密度（pBMD）的丢失。
64 名（年龄 35-65 岁）单侧髋关节骨关节炎患者被随机分为两组，分别接受 2 次地舒单抗或安慰剂皮下注射，分别在手术后 1-3 天和 6 个月时给予。通过双能 X 射线吸收法测量髋臼 pBMD 在 5 个感兴趣区域（ROI）。分析血清骨代谢标志物。通过 [18F] 正电子发射断层扫描/计算机断层扫描评估 64 名研究患者中的 32 名患者的假体周围成骨活性，以标准化摄取值（SUV）表示。
12 个月时，与安慰剂治疗组相比，地舒单抗治疗组患者的 5 个 ROI 中有 4 个和 1-5 个 ROI 总和的 pBMD 更高。24 个月后，地舒单抗治疗组患者的 pBMD 效果下降。地舒单抗治疗组患者的血清标志物在 12 个月内明显下降，但在 24 个月后反弹至基线以上水平。地舒单抗治疗组患者在 6 个月后所有 ROI 中 SUVs 均显著低于安慰剂治疗组，除 ROI5 外。
基于对次要终点的探索性分析，地舒单抗的应用似乎与保留髋臼 pBMD、降低骨代谢和减弱假体周围成骨活性有关。然而，鉴于地舒单抗停药后存在已知的反弹影响，这些效果不能持续存在。如果延长治疗或转向其他方案是否有助于降低杯松动的风险，仍有待研究。
