Membrane of hybrid chitosan–silica xerogel for guided bone regeneration

Chitosan–silica xerogel hybrid membranes were fabricated using a sol–gel process and their potential applications in guided bone regeneration (GBR) were investigated in terms of their in vitro cellular activity and in vivo bone regeneration ability. TEM observation revealed that the silica xerogel was dispersed in the chitosan matrix on the nanoscale. The hybrid membrane showed superior mechanical properties to chitosan in the wet state and the rapid induction of calcium phosphate minerals in simulated body fluid, reflecting its excellent in vitro bone bioactivity. Osteoblastic cells were observed to adhere well and grow actively on the hybrid membrane to a level higher than that observed on the chitosan membrane. The alkaline phosphatase activity of the cells was also much higher on the hybrid than on the chitosan membrane. The in vivo study in a rat calvarial model demonstrated significantly enhanced bone regeneration using the hybrid membrane compared to that observed using the pure chitosan one. Histomorphometric analysis performed 3 weeks after implantation revealed a fully closed defect in the hybrid membrane, whereas there was only 57% defect closure in the chitosan membrane.     

BMP-2 plasmid loaded PLGA/HAp composite scaffolds for treatment of bone defects in nude mice

We studied three different types of scaffolds, encapsulating bone morphogenetic protein-2 (BMP-2) plasmid, in terms of their performances in bone regeneration in nude mice. The plasmid was loaded into fibrous matrices in three different ways: coating of naked DNA (Group A) or DNA/chitosan nanoparticles (Group B) onto scaffolds after fiber fabrication by dripping, and encapsulation of DNA/chitosan nanoparticles into scaffold by mixing them with PLGA/DCM solution before fiber fabrication (Group C). Their individual performances were examined by soft X-ray observation, histological analysis and immunostaining of bone tissue. In addition, the BMP-2 protein concentration and alkaline phosphatase (ALP) activity in serum were monitored. The results revealed that the bioactivity of BMP-2 plasmid released from all three kinds of scaffolds was well maintained; this eventually helped improve the healing of segmental defects in vivo. Interestingly, the three kinds of scaffolds released DNA or DNA nanoparticles in different modes and their performances in bone healing were diverse. These observations demonstrate that the in vivo performance of these newly developed DNA delivery devices correlates well with their in vitro release profiles.     

两种方法治疗股骨干骨折合并较大游离骨块的效果比较

目的　比较两种方法治疗股骨干骨折合并较大游离骨块的效果差异。 方法　选择66例股骨干骨折合并较大游离骨块行切开复位内固定治疗患者。按游离骨块处理方法不同分为对照组（35例,仅复位固定,未行钻孔和植骨）和试验组（35例,行钻孔、松质骨孔内插秧式植骨和周围植骨,以及复位固定）。比较两组的手术时间、手术出血量、骨折愈合时间、并发症发生情况和末次随访时临近关节功能恢复（HSS法）。 结果　两组患者一般资料比较差异无统计学意义（P>0.05）。对照组的手术出血(847.58±147.53) ml和手术时间(138.43±12.10) min优于试验组（分别752.18±143.78 ml和115.27±11.31 min）,而试验组的骨折愈合时间（4.79±1.00 月）、骨延迟愈合（1/35）、骨不连（0）和内固定断裂（0）的发生率以及功能恢复（26/5/0/0）均优于对照组（分别为9.49±2.59 月,11/35,8/35,4/35和15/13/7/0）,差异均有统计学意义（P<0.05）。 结论　对于股骨干骨折合并较大游离骨块,仅复位固定的效果较差,而采用钻孔、松质骨植骨可以加快爬行替代愈合速度和改善骨折端的力学性能,骨折治疗效果明显优于前者。     

Human bone marrow stem cell-encapsulating calcium phosphate scaffolds for bone repair

Due to its injectability and excellent osteoconductivity, calcium phosphate cement (CPC) is highly promising for orthopedic applications. However, a literature search revealed no report on human bone marrow mesenchymal stem cell (hBMSC) encapsulation in CPC for bone tissue engineering. The aim of this study was to encapsulate hBMSCs in alginate hydrogel beads and then incorporate them into CPC, CPC–chitosan and CPC–chitosan–fiber scaffolds. Chitosan and degradable fibers were used to mechanically reinforce the scaffolds. After 21 days, that the percentage of live cells and the cell density of hBMSCs inside CPC-based constructs matched those in alginate without CPC, indicating that the CPC setting reaction did not harm the hBMSCs. Alkaline phosphate activity increased by 8-fold after 14 days. Mineral staining, scanning electron microscopy and X-ray diffraction confirmed that apatitic mineral was deposited by the cells. The amount of hBMSC-synthesized mineral in CPC–chitosan–fiber matched that in CPC without chitosan and fibers. Hence, adding chitosan and fibers, which reinforced the CPC, did not compromise hBMSC osteodifferentiation and mineral synthesis. In conclusion, hBMSCs were encapsulated in CPC and CPC–chitosan–fiber scaffolds for the first time. The encapsulated cells remained viable, osteodifferentiated and synthesized bone minerals. These self-setting, hBMSC-encapsulating CPC-based constructs may be promising for bone tissue engineering applications.     

外固定支架与小腿皮瓣在开放性胫腓骨骨折中的临床应用

目的：报道外固定支架结合小腿内侧筋膜皮瓣在修复开放性胫腓骨骨折骨外露中的手术方法及临床应用。方法：自1998年8月～2003年5月应用外同定支架结合逆行或顺行小腿内侧筋膜皮瓣一期修复开放性胫腓骨骨折并骨外露30例。结果：30例随访4个月到5年，术后筋膜皮瓣全部成活，切口Ⅰ期愈合28例，Ⅱ期愈合2例；27例胫腓骨骨折获得临床愈合，骨折愈合时间平均为5个月，骨折愈合时间最长为术后8个月；3例骨不愈合，1年后行切开植骨术而痊愈，不愈合率10％；2例有不同程度感染，其中1例并发慢性骨髓炎．术后感染率6．7％：结论：小腿内侧筋膜皮瓣血供良好，手术操作简单、不损伤小腿主要血管等优点，结合外固定支架技术是修复开放性胫腓骨骨折骨外露的一种可供选用的方法，特别适合于基层医院开展。     

骨髓间充质干细胞复合温敏水凝胶支架的制备

背景：壳聚糖及其衍生物制备的支架对细胞迁移和神经轴突再生有重要作用。壳聚糖及其衍生物的组织相容性好,易使干细胞在其表面附着生长,在神经组织工程具有较为广阔的应用前景。 目的：制备适宜骨髓间充质干细胞生长的壳聚糖/壳聚糖季铵盐/甘油磷酸钠温敏性水凝胶细胞支架,观察骨髓间充质干细胞在细胞支架中的生长情况。 方法：将壳聚糖进行季铵盐化改性处理,通过傅里叶变换红外光谱分析谱检测确定其生成。实验以壳聚糖与壳聚糖季铵盐配比为8∶1成功制备出较为稳定的壳聚糖/壳聚糖季铵盐/甘油磷酸钠温敏性温敏水凝胶细胞支架,观察成胶情况,并进行生物安全性检测。 结果与结论：实验在傅里叶变换红外光图谱上发现了季铵基基团的特征峰。细胞毒性实验显示,水凝胶浸提液干预的大鼠骨髓间充质干细胞无毒性。急性全身毒性实验显示,浸提液对大鼠体质量增加无明显影响,支架生物安全性较好。扫描电镜观察显示,骨髓间充质干细胞在细胞支架中能正常的生长和增殖。结果证实,实验成功制备了壳聚糖/壳聚糖季铵盐/甘油磷酸钠温敏性水凝胶细胞支架,适合骨髓间充质干细胞生长和增殖。     

Chitosan inhibits fibroblasts growth in Achilles tendon via TGF-β1/Smad3 pathway by miR-29b

Background and aim: Chitosan, is a natural polymer, plays an important role in prevention of tendon adhesion in tendon healing process. However, the molecular mechanisms underlying the prevention effect is unclear. Here we investigated the effects of chitosan on Achilles tendon injury rats and fibroblasts. Methods: Eight weeks after surgery, gliding excursion and the content of collagen fibers in Achilles tendon injury rats were determined to evaluate the chitosan effect on tendon healing. Fibroblasts isolated from scar tissue of repaired tendon were treated with different concentration of chitosan, and then cell inhibition, apoptosis and cell cycle were measured using MTT and Flow Cytometry respectively. The expression of microRNAs (miRNAs) was quantified by real-time PCR and protein expression of TGF-β1, Smad3 and P21 were quantified by western blotting. MiR-29b inhibitor was transfected in cells to evaluate the mechanism underlying the effects of chitosan on tendon fibroblasts. Results: The gliding excursion of repaired tendon was increased and the content of collagen fibers was decreased by chitosan in rats. Chitosan inhibited the fibroblasts growth and arrested cells in G1 phase. Chitosan also elevated the expression of miR-29b and P21 while reduced the levels of TGFβ1 and Smad3 in both repaired tendon and fibroblasts. In addition, miR-29b inhibitor revered the effects of chitosan on fibroblasts. Conclusions: The current study demonstrated that chitosan improving the condition of tendon healing after surgery, which is reduced by the high expression of miR-29b and its down-regulation of TGF-β1/Smad3 level and inhibition of fibroblasts growth.     

Evaluation of properties of chitosan as an adjuvant for inactivated influenza vaccines administered parenterally

Studies on mice showed that chitosan as an adjuvant for H5 inactivated influenza vaccines administered intramuscularly enhances significantly antibody titers and protective efficiency not only against homologous influenza viruses, but also against drift variants. Chitosan adjuvanted vaccines induced high antibody titers after a single immunization and with a low dose of antigen. High antibody titers remained for at least 6 months. Chitosan adjuvanted vaccine stored at 4°C preserves its adjuvant properties for at least 8 months. Chitosan stimulates proliferative and cytotoxic activity of splenic mononuclear leukocytes in mice and promotes an increase in the numbers of CD3, CD3/NK, I‐AK (MHC II), and H‐2Db (MHC I) cells. After intramuscular immunization, chitosan did not induce IgE antibodies and antibodies against chitosan itself. Chitosan is a promising adjuvant candidate for inactivated influenza vaccines administered parenterally. J. Med. Virol. 81:494–506, 2009. © 2009 Wiley‐Liss, Inc.     

煅烧骨/壳聚糖复合材料的制备及表征

文题释义：                                                                                                     天然骨：主要由无机的羟基磷灰石和有机的胶原成分构成,并具有一定的力学性能。以羟基磷灰石和磷酸三钙为主的磷酸盐材料拥有良好的骨传导性和部分骨诱导性,能够与宿主的骨直接发生骨结合,已成为目前临床应用最多的骨移植材料。 锻烧骨：是经高温锻烧异体动物骨所获得的无机材料,主要成分是羟基磷灰石,其钙磷比接近于人骨,拥有极好的生物相容性和优越的骨引导性。与人工合成的羟基磷灰石相比,不用考虑煅烧骨材料的结构形貌,而且材料来源广泛、制作成本低。 背景：壳聚糖具备优异的理化性能与良好的生物相容性,但其缺乏骨结合的生物活性,需要与其他材料复合用于骨组织修复中。 目的：将煅烧骨与壳聚糖复合,分析其理化性能和细胞毒性。 方法：采用溶液共混法制备煅烧骨与壳聚糖质量比分别为1/2、1/1、2/1的复合材料,表征3种复合材料的理化性能。在第5代小鼠成纤维细胞 L929中分别加入3种复合材料浸提液,CCK-8法检测复合材料的细胞毒性。 结果与结论：①X射线衍射和红外光谱显示,3种复合材料的主要成分均为羟基磷灰石与β-磷酸三钙,并且随着煅烧骨比例的增加,复合材料中的羟基磷灰石/β-磷酸三钙的特征衍射峰逐渐增强;②扫描电镜显示,煅烧骨颗粒较均匀地分散于壳聚糖介质中;③随着煅烧骨比例的增加,复合材料的抗压强度逐渐降低;④培养7 d时,3种复合材料浸提液中的细胞生长良好,形态无明显变化;培养9 d的时间内,3种复合材料浸提液中的细胞相对增殖率均在90%以上,细胞毒性均为1级,符合生物材料的安全标准;⑤结果表明,煅烧骨/壳聚糖复合材料具备良好的结构特征、理化性能及合适的抗压强度,并且安全无毒。 ORCID: 0000-0003-3519-4485(廖健) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

Studies on the distribution of macrophages derived from rat bone marrow cells in xenogeneic radiation chimaeras

Lethally-irradiated mice were injected with rat bone marrow cells and examined subsequently for the presence of rat macrophages, using an indirect fluorescent antibody test in conjunction with a fluorochrome-labelled phagocytic cell marker. Donor bone marrow cells were fractionated by (1) adherence, (2) magnetic removal of phagocytic cells containing ingested carbonyl iron and (3) treatment with lymphocyte-absorbed anti-rat macrophage serum either in vitro or in vivo. Extensive rat cell proliferation occurred in the resulting xenogeneic chimaeras by or after Day 4 and increased during the next week. The precursor of both the free and fixed macrophages was contained in the non-adherent, non-phagocytic population of bone marrow cells. The anti-macrophage serum was not selective and abolished the capability of bone marrow cells to proliferate.     

Differentiation and activity of human preosteoclasts on chitosan enriched calcium phosphate cement

Chitosan associated to various scaffolds has been shown to promote growth and mineral rich matrix deposition by osteoblasts in vitro, whereas its influence on osteoclast differentiation, which plays also a central role in bone remodeling, has never been described. The purpose of this study was to investigate the differentiation and activity of human preosteoclastic cells on calcium phosphate cement containing 2% chitosan (Cementek^®/chitosan) compared to the Cementek^® alone. Human primary osteoclast precursors were cultured directly on both biomaterials in the presence of rhM-CSF and rhRANK-L for 7 days. Using LIVE/DEAD fluorescent assay, tartrate-resistant acid phosphatase staining, scanning electron microscopy and quantitative RT-PCR, we demonstrated that incorporation of chitosan to Cementek^® does not affect the proliferation and adhesion of preosteoclasts but inhibits the formation of TRACP positive cells and prevents the osteoclastic resorption of the composite biomaterial compared to Cementek^® alone. This inhibitory effect of chitosan on osteoclast resorption activity should have important implications on bone formation and bone remodeling after in vivo implantation. Indeed, based on the positive results obtained in vivo by several investigators, one can suggest that this property of chitosan can be beneficial for bone regeneration.     

Incorporation of a sequential BMP-2/BMP-7 delivery system into chitosan-based scaffolds for bone tissue engineering

The aim of this study was to develop a 3-D construct carrying an inherent sequential growth factor delivery system. Poly(lactic acid-co-glycolic acid) (PLGA) nanocapsules loaded with bone morphogenetic protein BMP-2 and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanocapsules loaded with BMP-7 made the early release of BMP-2 and longer term release of BMP-7 possible. 3-D fiber mesh scaffolds were prepared from chitosan and from chitosan–PEO by wet spinning. Chitosan of 4% concentration in 2% acetic acid (CHI4–HAc2) and chitosan (4%) and PEO (2%) in 5% acetic acid (CHI4–PEO2–HAc5) yielded scaffolds with smooth and rough fiber surfaces, respectively. These scaffolds were seeded with rat bone marrow mesenchymal stem cells (MSCs). When there were no nanoparticles the initial differentiation rate was higher on (CHI4–HAc2) scaffolds but by three weeks both the scaffolds had similar alkaline phosphatase (ALP) levels. The cell numbers were also comparable by the end of the third week. Incorporation of nanoparticles into the scaffolds was achieved by two different methods: incorporation within the scaffold fibers (NP–IN) and on the fibers (NP–ON). It was shown that incorporation on the CHI4–HAc2 fibers (NP–ON) prevented the burst release observed with the free nanoparticles, but this did not influence the total amount released in 25 days. However NP–IN for the same fibers revealed a much slower rate of release; ca. 70% released at the end of incubation period. The effect of single, simultaneous and sequential delivery of BMP-2 and BMP-7 from the CHI4–HAc2 scaffolds was studied in vitro using samples prepared with both incorporation methods. The effect of delivered agents was higher with the NP–ON samples. Delivery of BMP-2 alone suppressed cell proliferation while providing higher ALP activity compared to BMP-7. Simultaneous delivery was not particularly effective on cell numbers and ALP activity. The sequential delivery of BMP-2 and BMP-7, on the other hand, led to the highest ALP activity per cell (while suppressing proliferation) indicating the synergistic effect of using both growth factors holds promise for the production of tissue engineered bone.     

Deficient antibody formation in the bone marrow of nude mice

The bone marrow of young adult nude mice was investigated as a site of antibody formation after intravenous immunization with the thymus-independent antigen Escherichia coli lipopolysaccharide (LPS). Mice heterozygous for the nu-gene were found to be capable of a plaque-forming cell (PFC) response in both spleen and bone marrow after primary and secondary immunization with LPS. Primary immunization of nude mice with LPS induced a normal PFC response in the spleen, but did not evoke the appearance of PFC in the bone marrow. During the secondary response the nude mice did show PFC activity in the bone marrow, but at a much lower level than their heterozygous littermates. At all time points after secondary immunization the number of splenic PFC was higher in nude mice than in the control mice.

Determination by immunofluorescence of cells containing cytoplasmic immunoglobulin (C-Ig cells) in the bone marrow of young adult nonimmune nude and heterozygous mice, revealed a three times higher number of C-IgM cells in the bone marrow of the heterozygous thymus-bearing mice. On the other hand, the number of splenic C-IgM cells was higher in the nude mice than in their heterozygous littermates. These results suggest that the presence of the thymus facilitates the appearance of mature antibody-forming cells in the bone marrow of young adult mice, irrespective of whether the generation of these cells is initiated by so called thymus-dependent or thymus-independent antigens.

     

人工骨复合物与经伤椎螺钉置入修复胸腰椎骨折可促进新骨形成

背景：单纯伤椎置钉疗法治疗胸腰椎骨折具有较好的疗效,但存在一定不足,如对于重度压缩或爆裂骨折适用性差、伤椎痛感强、易造成伤椎创面失神经支配和椎旁肌损伤及恢复较慢等。 目的：观察人工骨复合物并伤椎螺钉置入修复胸腰椎骨折的临床效果。 方法：纳入126例胸腰椎压缩骨折患者,其中对照组62例采用常规伤椎放置椎弓根螺钉方法治疗,试验组64例采用人工骨复合物联合伤椎放置椎弓根螺钉方法治疗。随访X射线观察两组骨折愈合、椎体前缘高度百分比、矢状位Cobb角及修复6个月后椎体高度丢失率变化。 结果与结论：所有患者均获得随访,修复后12-16个月,两组骨折椎体愈合完全。修复后1周,两组椎体前缘高度与矢状位Cobb角均较修复前改善(P < 0.01),两组间椎体前缘高度与矢状位Cobb角比较差异无显著性意义(P > 0.05);修复6个月后,试验组在伤椎创面可见明显新骨生成,患者基本无痛感,对照组新骨生成较慢,患者仍有痛感,两组椎体前缘高度丢失量与矢状位Cobb角矫正丢失量比较差异均无显著性意义(P > 0.05)。表明人工骨复合物联合伤椎置钉修复胸腰椎骨折促进新骨形成,有利于患者恢复。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

Vacuum-assisted infiltration of chitosan or polycaprolactone as a structural reinforcement for sintered cancellous bovine bone graft

Sintered cancellous bovine bone (SCBB) offers numerous advantages as a bone graft substitute material; however, its mechanical properties require improvement. In this study, SCBB was infiltrated with ε-polycaprolactone (PCL) or chitosan/monetite to improve mechanical properties while retaining valuable SCBB structure. Organic infiltrating solutions consisted of (i) chitosan and monetite (CaHPO(4) ) dissolved in hydrochloric acid; (ii) chitosan, monetite (CaHPO(4) ), and genipin dissolved in hydrochloric acid; or (iii) PCL polymer dissolved in tetrahydrofuran (THF). Porous SCBB materials were infiltrated with one of the three solutions using vacuum-assisted infiltration. Chitosan and CaHPO(4) were immobilized in the SCBB structure by reprecipitation following a pH increase in an ammonia atmosphere. Genipin was used in one sample group to immobilize chitosan via crosslinking. PCL was immobilized by evaporating the THF carrier solvent. Mechanical compression testing showed an improvement in ultimate stress for the SCBB with chitosan/CaHPO(4) infiltrates, whereas PCL samples showed an increase in modulus. All SCBB samples were found to demonstrate favorable in vitro biocompatibility when subjected to L929 mouse fibroblast cells but required a vigorous washing regime to eradicate toxic ammonia residue. In conclusion, infiltration of SCBB with a polymeric or organic/mineral composite matrix positively modifies SCBB mechanical properties in favor of bone grafting applications. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2581-2592, 2012.     

Potential role of myeloid-derived suppressor cells in transition from reaction to repair phase of bone healing process

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells with immunosuppressive functions; these cells play a key role in infection, immunization, chronic inflammation, and cancer. Recent studies have reported that immunosuppression plays an important role in the healing process of tissues and that Treg play an important role in fracture healing. MDSCs suppress active T cell proliferation and reduce the severity of arthritis in mice and humans. Together, these findings suggest that MDSCs play a role in bone biotransformation. In the present study, we examined the role of MDSCs in the bone healing process by creating a bone injury at the tibial epiphysis in mice. MDSCs were identified by CD11b and GR1 immunohistochemistry and their role in new bone formation was observed by detection of Runx2 and osteocalcin expression. Significant numbers of MDSCs were observed in transitional areas from the reactionary to repair stages. Interestingly, MDSCs exhibited Runx2 and osteocalcin expression in the transitional area but not in the reactionary area. And at the same area, cllagene-1 and ALP expression level increased in osteoblast progenitor cells. These data is suggesting that MDSCs emerge to suppress inflammation and support new bone formation. Here, we report, for the first time (to our knowledge), the role of MDSCs in the initiation of bone formation. MDSC appeared at the transition from inflammation to bone making and regulates bone healing by suppressing inflammation.     

Evaluation effects of chitosan for the extracellular matrix production by fibroblasts and the growth factors production by macrophages.

Chitosan is reported as an accelerator of wound healing. Histological findings of previous reports indicate that chitosan accelerates the reformation of connective tissue, however the details of the mechanism are not clear. In this study, firstly L929 mouse fibroblasts were cultured with chitosan and the production of extracellular matrix (ECM) was evaluated in vitro. Type I and III collagens and fibronectin were secreted by L929 with or without chitosan; however there was no significant difference in the amount of ECM between the control and the chitosan groups. Secondly, macrophages were stimulated with chitosan, and then transforming growth factor-beta 1 (TGF-beta1) and platelet-derived growth factor (PDGF) messenger ribonucleic acid (mRNA) expressions and production of their proteins were assayed in vitro. As a result, chitosan promoted the production of TGF-beta1 and PDGF. These results indicate that chitosan does not directly accelerate ECM production by fibroblast and the ECM production may increase by the growth factors.     

Memory T-cell competition for bone marrow seeding

The presence in the bone marrow of memory CD8 T cells is well recognized. However, it is still largely unclear how T-cell migration from the lymphoid periphery to the bone marrow is regulated. In the present report, we show that antigen-specific CD4 T cells, as well as antigen-specific CD8 T cells, localize to the bone marrow of immunized mice, and are sustained there over long periods of time. To investigate the rules governing T-cell migration to the bone marrow, we generated chimeric mice in which the lymphoid periphery contained two genetically or phenotypically distinct groups of T cells, one of which was identical to the host. We then examined whether a distinct type of T cell had an advantage over the others in the colonization of bone marrow. Our results show that whereas ICAM1 and CD18 molecules are both involved in homing to lymph nodes, neither is crucial for T-cell bone marrow colonization. We also observed that memory-phenotype CD44high T cells, but not virgin-type CD44-/low T cells, preferentially home to the bone marrow upon adoptive transfer to normal young mice, but not to thymectomized old recipients where an existing memory T-cell pool precludes their free access. Thus, T-cell colonization of the bone marrow uses distinct molecules from those implicated in lymph node homing, and is regulated both by the properties of the T cell and by the competitive efficacy of other T cells inhabiting the same, saturable niche. This implies that the homing potential of an individual lymphocyte is not merely an intrinsic property of the cell, but rather a property of the lymphoid system taken as a whole.     

同种异体骨复合自体红骨髓移植治疗关节周围骨折

背景：关节周围骨折复位后常出现骨缺损,需进行植骨填充骨缺损以早期支撑关节面以防止关节面塌陷及移位。同种异体骨是治疗骨缺损的移植材料,但成骨能力差。自体红骨髓有成骨能力,但同种异体骨复合自体红骨髓移植治疗关节周围骨折的临床效果有待评定。 目的：采用锁定板固定、同种异体骨复合自体红骨髓移植治疗关节周围骨折的临床效果。 方法：纳入河北医科大学第三医院骨伤科治疗关节周围骨折患者43例。采用切开解剖复位关节面、将红骨髓与同种异体骨颗粒复合体植于骨缺损处,植骨完成后常规解剖锁定板内固定。胫骨平台骨折采用内侧、外侧或双侧锁定板固定。桡骨远端骨折采用背侧或掌侧锁定板固定,胫骨远端骨折采用胫骨远端内侧或外侧板锁定内固定。 结果与结论：患者43例共随访12个月至6年,平均4.3年。X射线片及CT复查结果显示,43例患者达骨性愈合,塌陷骨折复位良好。其中新鲜骨折愈合时间2-6个月,平均4个月;陈旧骨折愈合时间3-7个月,平均5.5个月。植骨后43例患者无明显免疫排斥反应,2例患者切口渗液较多,经换药2周愈合。切口感染患者1例,经引流换药4周伤口愈合,随访4年1个月至今感染未复发。根据Mankin和Komender标准评定,同种骨移植满意患者40例,占93%;不满意患者3例,占7%。结果证实,在锁定板支撑固定下,异体松质骨与自体红骨髓复合体移植治疗周围关节骨折可以起到近期支撑作用,防止关节面塌陷及骨折移位,并为关节周围骨折骨缺损提供骨重建材料,远期可以达到骨折愈合的目的。     

The degree of correction in open-wedge high tibial osteotomy compromises bone healing: A consecutive review of 101 cases

BackgroundThe bone healing in open-wedge high tibial osteotomy (OWHTO) proceeds gradually by a filling of the osteotomy gap. This can comprise several risk factors.MethodsA retrospective study analysed the clinical and radiological course of 101 consecutive OWHTOs in 96 patients. The following risk factors were considered: age, body mass index, tobacco consumption, amount of tobacco consumption, severity of comorbidities, infection of the surgical area, occurrence of a lateral hinge fracture and the degree of correction. The bone healing was evaluated by using the modified Radiographic Union Score for Tibial fractures (RUST).ResultsA disturbance in bone healing was observed in 16 of the 101 osteotomies. Binary logistic regression analysis showed a correlation between the angle of the opening wedge and the development of a disturbance in bone healing (P = 0.002). The odds ratio indicated an increase in the risk of a disturbance in bone healing of 56% with each additional degree of correction. For the risk factor ‘age’ a statistical trend was recognizable (P = 0.077) with the risk of a disturbance in bone healing in higher age.ConclusionLateral hinge fractures seem not to have a detrimental effect on the filling of the osteotomy gap. An increase in the opening wedge bears the risk of a disturbance in bone healing.