Toth Jeffrey M, Bric Justin D
Department of Orthopaedic Surgery, The Medical College of Wisconsin Inc., Milwaukee, WI, USA.
Orthopaedic & Rehabilitation Engineering Center and Graduate Program in Dental Biomaterials, Marquette University, Milwaukee, WI, USA.
J Spine Surg. 2019 Dec;5(4):483-495. doi: 10.21037/jss.2019.10.13.
The objective of this study was to evaluate the host response to an interspinous process device [Device for Intervertebral Assisted Motion (DIAM)] based on a series of nine spine explants with a mean post-operative explant time of 35 months.
Explanted periprosthetic tissues were processed for histology and stained with H&E, Wright-Giemsa stain, and Oil Red O. Brightfield and polarized light microscopy were used to evaluate the host response to the device and the resultant particulate debris. The host response was graded per ASTM F981-04. Quantitative histomorphometry was used to characterize particle size, shape, and area per ASTM F1877-05. The presence or absence of bone resorption was also evaluated when bony tissue samples were provided.
Periprosthetic tissues demonstrated a non-specific foreign body response composed of macrophages and foreign body giant cells to the DIAM device in most of the accessions. The foreign body reaction was not the stated reason for explantation in any of the accessions. Per ASTM F981-04, a "very slight" to "mild" to "moderate" chronic inflammatory response was observed to the biomaterials and particulate, and this varied by tissue sample and accession. Particle sizes were consistent amongst the explant patients with mean particle size on the order of several microns. Osteolysis, signs of toxicity, necrosis, an immune response, and/or device related infection were not observed.
Cyclic loading of the spine can cause wear in dynamic stabilization systems such as DIAM. The fabric nature of the DIAM device's polyethylene terephthalate jacket coupled with the generation of polymeric particulate debris predisposes the device to a foreign body reaction consisting of macrophages and foreign body giant cells. Although not all patients are aware of symptoms associated with a foreign body reaction to a deeply implanted device, surgeons should be aware of the host response to this device.
本研究的目的是基于9个脊柱外植体（平均术后外植体时间为35个月），评估宿主对棘突间装置[椎间辅助运动装置（DIAM）]的反应。
将取出的假体周围组织进行组织学处理，并用苏木精和伊红染色、瑞氏-吉姆萨染色和油红O染色。采用明场和偏光显微镜评估宿主对该装置的反应以及由此产生的颗粒碎片。根据ASTM F981-04对宿主反应进行分级。采用定量组织形态计量学根据ASTM F1877-05对颗粒大小、形状和面积进行表征。当提供骨组织样本时，还评估了骨吸收的情况。
在大多数样本中，假体周围组织对DIAM装置表现出由巨噬细胞和异物巨细胞组成的非特异性异物反应。在任何样本中，异物反应都不是取出植入物的既定原因。根据ASTM F981-04，观察到对生物材料和颗粒有“非常轻微”至“轻度”至“中度”的慢性炎症反应，且这种反应因组织样本和样本而异。外植体患者的颗粒大小一致，平均颗粒大小约为几微米。未观察到骨溶解、毒性迹象、坏死、免疫反应和/或与装置相关的感染。
脊柱的循环负荷可导致DIAM等动态稳定系统的磨损。DIAM装置的聚对苯二甲酸乙二酯外套的织物性质以及聚合物颗粒碎片的产生，使该装置易发生由巨噬细胞和异物巨细胞组成的异物反应。尽管并非所有患者都意识到与深部植入装置的异物反应相关的症状，但外科医生应了解宿主对该装置的反应。
