Institute of Mechanical Engineering, University College London, London, UK.
Royal National Orthopaedic Hospital NHS Trust, Stanmore, UK.
J Orthop Res. 2024 Aug;42(8):1791-1800. doi: 10.1002/jor.25818. Epub 2024 Feb 26.
In revision total hip arthroplasty, achieving robust fixation is difficult and implant movement may occur over time. Bone may also rearrange around the implant as a result of mechanical loading, making the measurement of migration challenging. The study aimed to quantify changes in bone shape and implant position 1 year following acetabular reconstruction using custom three-dimensional-printed cups. This observational retrospective cohort study involved 23 patients with Paprosky type IIIB defects. Postop computed tomography scans taken within 1 week of surgery and at 1-year postsurgery were co-registered and analyzed. Three co-registration strategies were implemented including bone-to-bone and implant-to-implant. (1) Co-registration of the ipsilateral innominate bone (diseased anatomy) was used to measure changes in implant position. (2) Co-registration of the implant was carried out to quantify changes in the ipsilateral innominate bone shape. (3) Co-registration of the contralateral innominate bone (nondiseased anatomy) was performed to measure changes in the ipsilateral innominate bone shape and implant position. The median centroid distances (interquartile range [IQR]) were 2.3 mm (IQR: 3.7-1.7 mm) for changes in implant position, 2.4 mm (IQR: 3.6-1.6 mm) for changes in ipsilateral innominate bone shape, and 3.7 mm (IQR: 4.6-3.5 mm) for changes in ipsilateral innominate bone shape and implant position. Following acetabular reconstruction, implant movements and periprosthetic bone remodeling are physiological and of a similar extent. Surgeons and engineers should consider this when performing implant monitoring in these patients.
在翻修全髋关节置换术中，实现牢固固定较为困难，且随着时间的推移，植入物可能会移动。由于机械加载，骨骼也可能在植入物周围重新排列，这使得迁移的测量具有挑战性。本研究旨在使用定制的三维打印髋臼杯，定量测量髋臼重建后 1 年骨形态和植入物位置的变化。这是一项观察性回顾性队列研究，共纳入 23 例 Paprosky Ⅲ B 型髋臼缺损患者。术后 1 周内和术后 1 年进行的计算机断层扫描（CT）扫描进行了配准和分析。实施了三种配准策略，包括骨对骨和植入物对植入物。（1）采用同侧骨盆（病变解剖结构）的配准来测量植入物位置的变化。（2）进行植入物配准以量化同侧骨盆形状的变化。（3）对对侧骨盆（非病变解剖结构）进行配准，以测量同侧骨盆形状和植入物位置的变化。植入物位置变化的中位数中心距离（四分位距 [IQR]）为 2.3 mm（IQR：3.7-1.7 mm），同侧骨盆形状变化的中位数中心距离（IQR）为 2.4 mm（IQR：3.6-1.6 mm），同侧骨盆形状和植入物位置变化的中位数中心距离（IQR）为 3.7 mm（IQR：4.6-3.5 mm）。髋臼重建后，植入物的移动和假体周围骨的重塑是生理性的，且程度相似。在这些患者中进行植入物监测时，外科医生和工程师应考虑到这一点。
