Nursing Department, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Orthop Surg. 2023 Apr;15(4):1028-1036. doi: 10.1111/os.13680. Epub 2023 Feb 16.
At present, the most commonly used filler polymethyl methacrylate (PMMA) has the disadvantages of monomer toxicity, heat and leakage, and cannot be applied in young people. Therefore, finding a minimally invasive and good tissue-compatible alternative material has been a research hotspot in spine surgery in recent years. The aim of this study is to explore whether the memory alloy stent can avoid the complications of bone cement or not.
Four non-adjacent vertebral bodies of the thoracic and lumbar spine in the 18 10-month-old pigs were selected as the surgical site and were randomly divided into the scaffold group and the bone cement group. The memory alloy scaffold and PMMA (polymethyl methacrylate) bone cement were placed via percutaneous puncture, and intraoperative fluoroscopy and micro-CT were used to observe the changes in the height of scaffolds and bone cement in the vertebral body immediately, 6 weeks, and 12 weeks after operation, the microstructural parameters of the bone trabeculae (bone volume fraction, bone surface volume ratio, bone trabeculae number) were also measured.
The memory alloy stent could expand in the vertebral body, and its height gradually increased with time; additionally, the height of the bone cement mass did not change with time (p = 0.00). New bone trabeculae could grow into the scaffold along the gap, and the volume fraction of bone, the volume ratio of bone surface area, and the number of bone trabeculae increased gradually (p = 0.00). However, the volume fraction of bone, the volume ratio of bone surface area, and the number of trabeculae in the cement block decreased gradually (p = 0.00).
Memory alloy scaffolds have dynamic expansion characteristics in vivo, which can effectively avoid the complications of bone cement. Thus, it is beneficial to explore this minimally invasive treatment for vertebral compression fractures.
目前，最常用的填充剂聚甲基丙烯酸甲酯（PMMA）存在单体毒性、热和渗漏的缺点，不能用于年轻人。因此，寻找一种微创且组织相容性好的替代材料一直是近年来脊柱外科研究的热点。本研究旨在探讨记忆合金支架是否能避免骨水泥的并发症。
选择 18 头 10 月龄猪的胸腰椎非相邻 4 个椎体为手术部位，随机分为支架组和骨水泥组。经皮穿刺放置记忆合金支架和聚甲基丙烯酸甲酯（PMMA）骨水泥，术中透视和微 CT 观察术后即刻、6 周和 12 周支架和骨水泥在椎体中的高度变化，测量骨小梁的微观结构参数（骨体积分数、骨表面体积比、骨小梁数）。
记忆合金支架可在椎体中扩张，其高度随时间逐渐增加，而骨水泥的高度随时间无变化（p=0.00）。新的骨小梁可沿间隙长入支架，骨体积分数、骨表面面积比和骨小梁数逐渐增加（p=0.00）。然而，骨水泥块的骨体积分数、骨表面面积比和小梁数逐渐减少（p=0.00）。
记忆合金支架在体内具有动态扩张特性，能有效避免骨水泥的并发症。因此，探索这种微创治疗椎体压缩性骨折的方法是有益的。
