Evaluation of poly(lactide-co-glycolide)/hydroxyapatite nanofibres for reconstruction of critical-sized segmental bone defects in a canine model

The treatment of segmental bone defects is a challenging problem for both human and veterinary medicine. Various biomaterials have successfully been used to treat these defects. Numerous recent in vitro studies have shown the potential of treating bone tissues using poly(lactide-co-glycolide)/hydroxyapatite (PLGA/HAp) nanofibres, which are fabricated using electrospinning. The purpose of this study was to evaluate the possibility of using a bone scaffold of PLGA/HAp nanofibres to repair critical-sized segmental bone defects in a canine model. The experimental bone defects were created in a 15 mm-long region of the radius. The area of the defect in each of 10 Beagle dogs was treated with a transplant of PLGA/HAp nanofibres in gelatin. The control group consisted of five Beagle dogs with similar defect sites that were not treated. Radiological and histological examinations were used to monitor the response of PLGA/HAp nanofibre-treated canine bone. Micro-computed tomography (micro-CT) was used to evaluate bone mass parameters 18 weeks after treatment in the experimental bone defect group. Our radiological and histological results showed that the PLGA/HAp nanofibre is biodegradable in the defect sites and replaces new bone tissue. Micro-CT showed that bone mass parameters were significantly (P < 0.05) increased in the critical-sized segmental bone defects of PLGA/HAp nanofibre-treated animals as compared to those of untreated animals. Based on these results, we conclude that PLGA/HAp nanofibres may be used as a bone scaffold biomaterial in canines.

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Experimental study on repair of large segmental bone defects of goat femur by nano calcium-deficient hydroxyapatite-multi (amino acid) copolymer membrane tubes

Journal of Biomaterials Applications ◽

10.1177/08853282211000298 ◽

2021 ◽

pp. 088532822110002

Author(s):

Yan Xiong ◽

Hong Duan ◽

Bin Zhang ◽

Cheng Ren ◽

Zeping Yu ◽

...

Keyword(s):

Amino Acid ◽

Bone Defects ◽

Torsional Stiffness ◽

Control Group ◽

Allogenic Bone ◽

Acid Copolymer ◽

Membrane Tube ◽

Segmental Bone ◽

Experimental Group ◽

Segmental Bone Defects

Objective The purpose of this study was to observe feasibility of nano calcium-deficient hydroxyapatite-multi (amino acid) copolymer (n-CDHA-MAC) membrane tubes in repairing goat femurs’ large defects. Methods Twelve goats were divided into two groups, whose femurs were created 30 mm segmental bone defects and then implants were performed. In experimental group, the bone defect of right femur was reconstructed by n-CDHA-MAC membrane tube, while left side was reconstructed by allogenic bone tube in control group. Every three goats were sacrificed at 4, 8, 16, 24 weeks after operation respectively. General observation, X-ray analysis, histology, Scanning electron microscope (SEM) examination and protein level comparison of BMP-2 were conducted to evaluate the effects of repairing segmental bone defects. Results All goats recovered well from anesthesia and surgical interventions. The radiographic evaluations showed that periosteal reaction outside of the membrane tubes and allogenic bone tubes were observed 4 weeks after surgery. At 16 weeks, callus was continuously increased in experimental group, which was more obvious than control group. At 24 weeks, callus outside of the membrane tubes connected together. Histologic evaluation showed fibro-cartilage callus was evolved into bony callus in experimental group, which was more obvious than control group at 8 and 16 weeks. The protein expression level of BMP-2 increased at 4, 8 weeks and peaked at 16 weeks in experimental groups. There were statistical differences at 8 and 16 weeks ( P < 0.05). At each time point in 8, 16, 24 weeks after surgery, the bending stiffness, torsional stiffness and compressive strength of the two groups were similar, and there was no significant difference ( P > 0.05). Conclusions This novel surface degradation n-CDHA-MAC membrane tube has good ability to maintain enough membrane space, which can provide long-term and stable biomechanical support for large bone defects and integrate well with the surrounding bone.

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Comparison between Tonifying Kidney Yang and Yin in Treating Segmental Bone Defects Based on the Induced Membrane Technique: An Experimental Study in a Rat Model

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2020/6575127 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Zhen Shen ◽

Zehua Chen ◽

Xiaodong Shi ◽

Tao Wang ◽

Minling Huang ◽

...

Keyword(s):

Bone Repair ◽

Bone Defects ◽

Treated Group ◽

Control Group ◽

Induced Membrane ◽

Membrane Technique ◽

The Difference ◽

Segmental Bone ◽

Stage 1 ◽

Segmental Bone Defects

Tonifying kidney therapy consisting of tonifying kidney yang and yin is the basic principle of Chinese medicine in treating segmental bone defects (SBDs). Previous studies have demonstrated the presence of the differences between tonifying kidney yang and yin in bone metabolism of osteoporosis and distraction osteogenesis models. However, whether the difference between the two tonifying kidney methods in bone repair for the induced membrane (IM) technique occurs or what is the difference remain unclear. Angiogeneic-osteogenic coupling plays an important role in bone repair and the induced membrane couples angiogenesis with the later osteogenesis during the IM process. This study aimed at investigating the effects of tonifying kidney yang (total flavonoids of Rhizoma Drynariae, TFRD) and yin (plastrum testudinis extract, PTE) on angiogenesis and osteogenesis in the IM-treated SBDs. Rats of 6 mm tibia bone defect model treated with IM were divided into five groups: the control group, the model group, the tonifying kidney yang group (TFRD-treated group), the tonifying kidney yin group (PTE-treated group), and the western medicine group. At 4 weeks after insertion of the polymethylmethacrylate (PMMA), three caudal vertebrae from the tail in each rat were implanted into the 6 mm defect gap. Radiographical, histological, immunohistochemical, and immunofluorescent analyses were performed to assess bone and vessel formation at 4 or 12 weeks after insertion of the PMMA, respectively. Our results revealed that TFRD and PTE were beneficial to both angiogenesis and osteogenesis. TFRD exerted a better effect on angiogenesis than PTE and achieved a better result in stage 1 rather than in stage 2 of IM, whereas PTE was superior to TFRD in osteogenesis and achieved a better result in stage 2 instead of stage 1. Collectively, these findings elucidated the beneficial effects of tonifying kidney yang and yin on angiogenesis and osteogenesis of SBD repair during the IM process, as well as the difference that tonifying kidney yang surpasses tonifying kidney yin in angiogenesis while tonifying kidney yin outperforms tonifying kidney yang in osteogenesis, which suggests that the combination between the application of tonifying kidney yang method in stage 1 of IM and tonifying kidney yin method in stage 2 may achieve better repair efficiency.

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Analysis of the early therapeutic effects and healing outcomes of segmental bone defects in the ankle joint treated with the induced membrane/wrapped bone grafting technique

10.21203/rs.3.rs-19889/v1 ◽

2020 ◽

Author(s):

Wenbin Zhao ◽

Maopeng Wang ◽

Xingshi Lin ◽

Feng Tu ◽

Dongfeng Zhao

Keyword(s):

Body Temperature ◽

Bone Cement ◽

Ankle Joint ◽

Bone Defects ◽

Micro Ct ◽

Induced Membrane ◽

Membrane Technique ◽

Induced Membrane Technique ◽

Segmental Bone ◽

Segmental Bone Defects

Abstract BackgroundThe current research explores the early therapeutic efficacy and healing outcomes of segmental bone defects in the ankle joint treated with induced membrane technique. MethodsA segmental bone defect model of ankle joint was first constructed by removing 2mm bone from the ankle joint of the rat, and then the induced membrane treatment was performed in two steps: the first step was to implant polymethyl methacrylate bone cement after thorough debridement, followed by the second step to remove bone cement after membrane formation and to replace with the rat’s autologous cancellous bone. The physiological indicators (body temperature and body weight) of the rats and the TNF-α and CRP in the blood were monitored post-surgery, and the efficacy was analyzed based on the above combining Micro-CT and X-ray analysis. Postoperative histological analysis of the tissue morphology of partial induced membrane was performed in rats at 2, 4, 6, and 8 weeks to evaluate the tissue status at the sites of bone defect. ResultsResults showed that the rats survived well after operation: the body temperature slowly decreased, and the CRP was also gradually reduced to normal; the 12-week Micro-CT and palpation indicated a satisfying bone healing trend; histological studies found calcified tissue in the second week post-operation, and vascular network was established in the induced sites at 8 weeks.ConclusionThe study proves that the induced membrane technique can effectively treat segmental bone defects of ankle joint, and is less prone to infection.

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