Corban Jason, Bowler Adam R, Glass Evan A, Brownhill James R, Myers Cole, Hodorek Brian, Purdy Matthew, Vasconcellos Daniel, Le Kiet, Austin Luke S, Cuff Derek J, Murthi Anand M, Smith Matthew J, Wiater J Michael, Jawa Andrew
Department of Orthopaedic Surgery, New England Baptist Hospital, Boston, MA, USA.
Department of Orthopaedic Surgery, New England Baptist Hospital, Boston, MA, USA; Boston Sports and Shoulder Center Research Foundation, Waltham, MA, USA.
J Shoulder Elbow Surg. 2025 Feb;34(2):606-616. doi: 10.1016/j.jse.2024.06.005. Epub 2024 Aug 5.
Augmented baseplates can be effective at addressing eccentric glenoid wear in reverse total shoulder arthroplasty. However, these implants often come in a limited number of predetermined shapes that require additional reaming to ensure adequate glenoid seating. This typically involves complex instrumentation and can have a negative impact on implant stability. Modular baseplate augmentation based on intraoperative measurements may allow for more precise defect filling while preserving glenoid bone. The purpose of this investigation was to assess the stability of a novel ringed baseplate with modular augmentation in comparison with nonaugmented standard and ringed baseplate designs.
In this biomechanical study, baseplate micromotion was tested for 3 constructs according to the American Society for Testing and Materials guidelines. The constructs included a nonaugmented curved baseplate, a nonaugmented ringed baseplate, and a ringed baseplate with an 8-mm locking modular augmentation peg. The nonaugmented constructs were mounted flush onto polyurethane foam blocks, whereas the augmented baseplate was mounted on a polyurethane block with a simulated defect. Baseplate displacement was measured before and after 100,000 cycles of cyclic loading.
Before cyclic loading, the nonaugmented and augmented ringed baseplates both demonstrated significantly less micromotion than the nonaugmented curved baseplate design (81.1 μm vs. 97.2 μm vs. 152.7 μm; P = .009). After cyclic loading, both ringed constructs continued to have significantly less micromotion than the curved design (105.5 μm vs. 103.2 μm vs. 136.6 μm; P < .001). The micromotion for both ringed constructs remained below the minimum threshold required for bony ingrowth (150 μm) at all time points.
In the setting of a simulated glenoid defect, locked modular augmentation of a ringed baseplate does not result in increased baseplate micromotion when compared with full contact nonaugmented baseplates. This design offers a simple method for tailored baseplate augmentation that can match specific variations in glenoid anatomy, limiting the need for excessive reaming and ultimately optimizing the environment for long-term implant stability.
在反式全肩关节置换术中，增大的基板可有效解决关节盂偏心磨损问题。然而，这些植入物通常只有有限数量的预定形状，需要额外扩孔以确保关节盂合适的就位。这通常涉及复杂的器械操作，并且可能对植入物稳定性产生负面影响。基于术中测量的模块化基板增大可能允许在保留关节盂骨的同时更精确地填充缺损。本研究的目的是评估一种新型带模块化增大的环形基板与未增大的标准和环形基板设计相比的稳定性。
在这项生物力学研究中，根据美国材料与试验协会指南对3种结构的基板微动进行测试。这些结构包括未增大的弯曲基板、未增大的环形基板和带有8毫米锁定模块化增大栓的环形基板。未增大的结构平齐安装在聚氨酯泡沫块上，而增大的基板安装在带有模拟缺损的聚氨酯块上。在100,000次循环加载前后测量基板位移。
在循环加载前，未增大和增大的环形基板的微动均明显小于未增大的弯曲基板设计（81.1微米对97.2微米对152.7微米；P = 0.009）。循环加载后，两种环形结构的微动仍明显小于弯曲设计（105.5微米对103.2微米对136.6微米；P < 0.001）。在所有时间点，两种环形结构的微动均保持在骨长入所需的最小阈值（150微米）以下。
在模拟关节盂缺损的情况下，与完全接触的未增大基板相比，带锁定模块化增大的环形基板不会导致基板微动增加。这种设计提供了一种简单的定制基板增大方法，可匹配关节盂解剖结构的特定变化，减少过度扩孔的需要，并最终优化长期植入物稳定性的环境。
