Neumann Hanjo, Breer Stefan, Reimers Nils, Kasch Richard, Schulz Arndt-Peter, Kienast Benjamin
BG Trauma Hospital, Hamburg, Germany.
Medical Faculty, University of Lübeck, Lübeck, Germany.
J Orthop Surg Res. 2015 Jan 28;10:18. doi: 10.1186/s13018-015-0156-1.
Screw fixation and fragment anchoring in osteoporotic bones is often difficult. Problems like the cut out phenomenon and implant migration in osteoporotic bones have been reported. One possibility of improving the anchoring force of screws is augmentation of the screw. Cement-augmented screws in spinal surgery could exhibit a better anchoring in osteoporotic bones.
The purpose of this study was to examine the effect of screw augmentation using a resorbable polymer. Ultrasound-activated biodegradable pins were used for the purpose of a resorbable augmentation technique. Cannulated screws were inserted into the femur of 12 sheep and augmented by an ultrasound-activated polylactic acid (PLDLA) pin. In a paired approach, four screws were implanted in each animal: 2× a 10-mm thread and 2× a 20-mm thread, both of which were augmented with polymer. Both screws, named A and B, were also applied without augmentation (control group) and implanted into the contralateral hind limb. After 4, 8, and 12 weeks, the sheep were euthanized and a macroscopical and histological examination followed.
The polymer spread well out of the screws into the cancellous lacunae. Around the polymer, the peripheral bone showed signs of healthy and active bone tissue. No evidence of inflammation or infection was observed. The boneto-implant contact was significantly higher in the augmented screws. Biocompatibility was proven in histopathological examination. After 12 weeks, no pathological changes were found.
Ultrasound-activated polymer augmentation of cannulated screws may improve the anchoring in osteoporotic bone.
Can screw augmentation using a resorbable polymer improve the bone-to-implant contact in case of screw osteosynthesis? Is there any effect on the surrounding tissue by the induced temperature and liquefied polymer? Can biocompatibility be proven by this new osteosynthesis?
Screw augmentation by ultrasound-activated biopolymer leads to a significant higher bone-to-implant contact than pure screw osteosynthesis. No tissue damage could be observed by the application of the SonicFusion™.
The ovine in vivo study concept can simulate physiological conditions. First examination of screw augmentation by ultrasound-activated biopolymer. No biomechanical testing of the higher bone-to-implant contact by now.
在骨质疏松性骨中进行螺钉固定和碎骨片锚定通常很困难。已有报道称在骨质疏松性骨中存在螺钉穿出现象和植入物移位等问题。提高螺钉锚固力的一种可能性是对螺钉进行增强。脊柱手术中使用骨水泥增强的螺钉在骨质疏松性骨中可能表现出更好的锚固效果。
本研究的目的是检验使用可吸收聚合物增强螺钉的效果。超声激活的可生物降解销钉用于可吸收增强技术。将空心螺钉插入12只绵羊的股骨中，并用超声激活的聚乳酸（PLDLA）销钉进行增强。采用配对方法，在每只动物体内植入4枚螺钉：2枚10毫米螺纹的螺钉和2枚20毫米螺纹的螺钉，两者均用聚合物增强。这两种螺钉，分别命名为A和B，也在未增强的情况下（对照组）植入对侧后肢。在4周、8周和12周后，对绵羊实施安乐死并进行宏观和组织学检查。
聚合物从螺钉中很好地扩散到松质骨腔隙中。在聚合物周围，周边骨显示出健康且活跃的骨组织迹象。未观察到炎症或感染迹象。增强后的螺钉骨与植入物的接触明显更高。组织病理学检查证实了生物相容性。12周后，未发现病理变化。
超声激活聚合物增强空心螺钉可能改善在骨质疏松性骨中的锚固效果。
在螺钉骨固定的情况下，使用可吸收聚合物增强螺钉能否改善骨与植入物的接触？诱导温度和液化聚合物对周围组织有何影响？这种新的骨固定方法能否证明生物相容性？
超声激活生物聚合物增强螺钉导致骨与植入物的接触显著高于单纯的螺钉骨固定。应用SonicFusion™未观察到组织损伤。
绵羊体内研究概念可模拟生理条件。首次对超声激活生物聚合物增强螺钉进行研究。目前尚未对更高的骨与植入物接触进行生物力学测试。
