Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada; School of Biomedical Engineering, Western University, London, ON, Canada; Lawson Health Research Institute, London, ON, Canada.
Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada.
J Shoulder Elbow Surg. 2022 Mar;31(3):591-600. doi: 10.1016/j.jse.2021.11.007. Epub 2021 Dec 27.
Reverse shoulder arthroplasty (RSA) is rapidly being adopted as the standard procedure for a growing number of shoulder pathologies. Lateralization of the glenoid component is known to reduce the incidence of scapular notching and possibly improve postoperative range of motion. A number of methods are used for glenoid component lateralization, including bony increased-offset reverse shoulder arthroplasty (BIO-RSA) and porous metal-augmented baseplates. Presently, there exists little comparative literature on bone vs. metal lateralization. Therefore, the purpose of this study was to compare BIO-RSA to metal-augmented glenoid baseplates by assessing clinical outcomes and baseplate migration using model-based radiostereometric analysis.
A power analysis indicated 40 patients would be required for this radiostereometric study. Therefore, 41 shoulders were prospectively randomized to receive either glenoid bone grafting (BIO-RSA) or a porous metal-augmented wedge-shaped titanium baseplate for primary reverse shoulder arthroplasty. At the time of primary surgery, all patients also underwent implantation of 8 tantalum marker beads in the glenoid and coracoid. Following surgery, participants were imaged using a calibrated, stereo radiographic technique. Radiographs were acquired at 6 weeks (baseline), 3 months, 6 months, 1 year, and 2 years postoperatively. Migration of the prosthesis was compared between bone and metal lateralization groups at each time point using a mixed effects model with Bonferroni test for multiple comparisons. Outcome measures were acquired preoperatively and 2 years postoperatively.
No significant differences were observed along any translation or rotation axis at any time point for either glenoid fixation group (P ≥ .175). Mean total glenoid component translation (± standard deviation) 2 years postoperatively was 0.4 ± 0.2 mm and 0.5 ± 0.3 mm for BIO-RSA and metal-augmented baseplates, respectively (P = .784). No significant differences were observed between groups in active range of motion; pain; American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form score; Simple Shoulder Test score; Disabilities of the Arm, Shoulder, and Hand score; Constant Shoulder score; or Subjective Shoulder Value (P ≥ .117), with the exception of increased active external rotation in the BIO-RSA cohort (P = .036).
This randomized clinical trial assessed reverse shoulder arthroplasty glenoid component migration using model-based radiostereometric analysis. At 2-year follow-up, our results indicate both BIO-RSA and porous metal wedge augmented baseplates provide stable initial fixation, which is maintained at 2 years' follow-up, with no substantial differences in clinical outcomes.
反肩置换术（RSA）作为越来越多的肩部病变的标准治疗方法，其应用正在迅速普及。肩胛盂组件的外侧化可降低肩胛切迹的发生率，并可能改善术后活动范围。有多种方法可用于肩胛盂组件的外侧化，包括骨增加偏移的反肩置换术（BIO-RSA）和多孔金属增强的底座。目前，关于骨与金属外侧化的比较文献很少。因此，本研究的目的是通过使用基于模型的放射立体分析来评估临床结果和底座迁移，比较 BIO-RSA 和多孔金属增强的肩胛盂底座。
一项功效分析表明，这项放射立体研究需要 40 名患者。因此，前瞻性随机将 41 例肩部分为接受骨移植物（BIO-RSA）或多孔金属增强楔形钛底座的原发性反肩置换术。在初次手术时，所有患者还在肩胛盂和喙突中植入了 8 个钽标记珠。手术后，参与者使用校准的立体射线照相技术进行成像。术后 6 周（基线）、3 个月、6 个月、1 年和 2 年拍摄 X 光片。使用混合效应模型和 Bonferroni 检验进行多次比较，比较每组在每个时间点的假体迁移。在术前和术后 2 年获得了结果测量值。
在任何时间点，两组肩胛盂固定组在任何平移或旋转轴上均无显著差异（P≥.175）。术后 2 年，总肩胛盂组件平移的平均值（±标准差）分别为 0.4±0.2mm 和 0.5±0.3mm，BIO-RSA 和金属增强底座组（P=0.784）。两组在主动活动范围、疼痛、美国肩肘外科医生标准肩评估表评分、简单肩测试评分、手臂、肩部和手残疾评分、常数肩评分或主观肩值方面均无显著差异（P≥.117），BIO-RSA 组的主动外旋增加除外（P=0.036）。
这项随机临床试验使用基于模型的放射立体分析评估了反肩置换术肩胛盂组件的迁移。在 2 年的随访中，我们的结果表明，BIO-RSA 和多孔金属楔形增强底座均提供了稳定的初始固定，在 2 年的随访中得到了维持，临床结果无实质性差异。
