Heřt Jan, Havránek Martin, Daniel Matej, Sosna Antonín
1st Department of Orthopaedics, Motol University Hospital, 150 06 Prague, Czech Republic.
Department of Mechanics, Biomechanics and Mechatronics, Czech Technical University in Prague, 166 36 Prague, Czech Republic.
J Clin Med. 2025 Jul 27;14(15):5307. doi: 10.3390/jcm14155307.
: Short-stem hip replacements are designed to provide improved load distribution and to mimic natural biomechanics. The interplay between implant design, positioning, and resulting bone biomechanics in individual patients remains underexplored, and the relationship between radiographically assessed bone remodeling around short stems and biomechanical predictions has not been previously reported. : This study evaluated three short-stem hip implant designs: Proxima, Collo-MIS, and Minima. Postoperative bone remodeling patterns were analyzed, categorizing remodeling as bone gain, bone loss, or no observable activity, with changes tracked over time. Patient-specific biomechanical models were generated from 6-week postoperative radiographs. Finite element simulations incorporated body weight and gluteal muscle forces to estimate stress and strain distributions within the proximal femur. Strain energy was then applied to a mechanostat-based remodeling algorithm to predict bone remodeling patterns. These biomechanical predictions were compared to observed radiographic remodeling at 2 years post-surgery. A validated biomechanical model was further used to simulate different postoperative positions of the three types of stems. : No differences in bone remodeling patterns were observed among the three short-stem designs. Computational modeling demonstrated a statistically significant correlation between predicted remodeling and radiographic measurements at 2 years ( < 0.001). Proxima stems showed a tendency towards increased cortical bone loading under pronounced varus or valgus position in comparison to other two stems, although this observation requires further validation. : This exploratory study demonstrates the feasibility of using biomechanical modeling to estimate bone remodeling around short-stem hip implants based on early postoperative radiographs. While the results are promising, they should be interpreted with caution due to the limited cohort size. The proposed modeling approach may offer clinical value in evaluating implant behavior and informing patient-specific treatment strategies. However, further research with larger populations is necessary to refine and validate these predictive tools.
短柄髋关节置换术旨在改善负荷分布并模拟自然生物力学。植入物设计、定位与个体患者所产生的骨生物力学之间的相互作用仍未得到充分研究，且此前尚未报道过短柄周围经影像学评估的骨重塑与生物力学预测之间的关系。
Proxima、Collo-MIS和Minima。分析术后骨重塑模式，将重塑分类为骨增加、骨丢失或无明显活动，并随时间跟踪变化。从术后6周的X光片生成患者特异性生物力学模型。有限元模拟纳入体重和臀肌力量，以估计股骨近端内的应力和应变分布。然后将应变能应用于基于机械调节仪的重塑算法，以预测骨重塑模式。将这些生物力学预测结果与术后2年观察到的影像学重塑结果进行比较。进一步使用经过验证的生物力学模型来模拟三种类型柄的不同术后位置。
三种短柄设计之间未观察到骨重塑模式的差异。计算建模表明，预测的重塑与术后2年的影像学测量之间存在统计学显著相关性（<0.001）。与其他两种柄相比，Proxima柄在明显内翻或外翻位置下显示出皮质骨负荷增加的趋势，尽管这一观察结果需要进一步验证。
这项探索性研究证明了使用生物力学建模根据术后早期X光片估计短柄髋关节植入物周围骨重塑的可行性。虽然结果很有前景，但由于队列规模有限，应谨慎解释。所提出的建模方法可能在评估植入物行为和为患者特异性治疗策略提供信息方面具有临床价值。然而，需要对更大人群进行进一步研究，以完善和验证这些预测工具。
