Responsiveness of osteoblastic and osteolytic bone metastases to vitamin D analogs

Bone is the primary site of metastases in advanced androgen-independent prostate cancer. These metastases are primarily bone-forming, although the presence of osteolytic response has also been reported. Bone-homing therapy is a strategy based on the popular seed-and-soil relationship between the epithelial malignant cells and the bone stroma. Calcitriol (1,25-dihydroxyvitamin D3) and its synthetic analogs (deltanoids) are drugs that have a direct effect on both the skeleton and the invading metastatic cells and, therefore, are considered useful in the treatment of advanced prostate cancer. In this article, I review the nature of the response induced by the malignant cells in the bone (bone formation or bone resorption) and how it affects the outcome of a vitamin D analog treatment in preclinical models of metastatic bone disease.     

重组合异种骨修复良性骨肿瘤及瘤样病变骨缺损

目的研究重组合异种骨(RBX)修复良性骨肿瘤及瘤样病变刮除术后遗留的骨缺损的临床应用价值。方法应用 RBX 修复64例良性骨肿瘤及瘤样病变刮除术后遗留的83处骨缺损。患者平均年龄26.5 岁,肿瘤类型依次为骨囊肿、骨纤维结构不良、内生软骨瘤、骨样骨瘤、动脉瘤样骨囊肿、非骨化性纤维瘤等,观察患者术后全身及切口局部反应,相关免疫学检测,X 线片检查,平均随访时间14个月。结果全部患者未见明显全身反应,相关免疫学检测无明显异常,随访见所有患者术后3～6个月均有 RBX 降解和骨替代现象发生。结论良性骨肿瘤及瘤样病变刮除后利用 RBX 填充修复骨缺损,无明显不良反应,并发症少,经骨替代后可真正完成骨修复。     

多孔磷酸三钙修复良性骨肿瘤骨缺损的临床研究

目的评价多孔磷酸三钙(Tricalcium Phosphate,TCP)治疗良性或侵袭性骨肿瘤骨缺损临床效果。方法 2007年9月至2010年1月对19例良性或侵袭性骨肿瘤患者采用多孔磷酸三钙修复骨缺损,其中男12例,女7例。年龄3~58岁,平均年龄22.4岁。随访3~30月,平均13月。采用VAS评分反应疼痛缓解程度,X线检查并Lane-Sandhu评分评定骨愈合情况,分析X片中植骨区灰度变化评估TCP的降解情况。结果 VAS评分术前、术后1周、术后12周、术后24周各组间总体差别比较<0.01,说明术后疼痛逐渐缓解。Lane-sandhu评分三个时段差异<0.001,说明人工骨随时间推移有明显的骨修复效果。认为手术中应当将多孔TCP人工骨松散放置,不要施加任何挤压力。结论多孔磷酸三钙人工骨可以用作良性或侵袭性骨肿瘤骨缺损的修复。     

自固化磷酸钙人工骨(CPC)修复骨肿瘤骨缺损的初步临床应用

评价自固化磷酸钙人工骨（CPC）治疗骨肿瘤缺损早期临床效果。方法对23例骨瘤患者行病灶刮除、国产CPC填塞修补术。患者年龄8～45岁，平均24.3岁。术后血液免疫学及X线检查，随访1～2年。结果CPC固化时间在15～30min，平均20min。临床使用后未见明显局部和全身不良反应，6个月后逐渐出现降解。随访X线片示CPC与宿主骨直接愈合，与原骨界面间接触紧密无间隙，骨缺损处解剖形状完全恢复。     

氰基丙烯酸酯类骨黏合剂：应用在骨折骨缺损修复中的潜能和优势

BACKGROUND: Cyanoacrylate adhesives are widely used in medical fields such as hemostatic agent, wound closure and medical embolism. OBJECTIVE: To point out the problems and focus of research of cyanoacrylate adhesives used in the orthopedic field through reviewing the properties and research progress of cyanoacrylate adhesives in fracture fixation and relevant modification research. METHODS: Articles related to cyanoacrylate as bone adhesives and relevant modification studies were retrieved in CNKI and PubMed databases (2008-01/2015-12). The key words were “cyanoacrylate, fracture, bone defect” in Chinese and English, respectively. A total of 40 articles based on inclusion and exclusion criteria were obtained for the further review. RESULTS AND CONCLUSION: Cyanoacrylate adhesives have been widely used in medical fields such as vascular anastomosis and embolization in vascular surgery, soft tissue repair, skin closure. However, it is still in the stage of animal experiments as bone adhesives for fracture fixation in load-bearing parts. Importantly, there are two problems to be solved. First, cyanoacrylate adhesives could not complete the fixation of fracture in the load-bearing parts because of viscosity and biomechanical deficiencies. Second, it still needs to observe whether the adhesives on the fracture end hinder the growth of bone. In conclusion, modification of cyanoacrylate shows a great potential in fracture fixation compared with traditional internal fixation methods. This new method has a wonderful prospect in clinical treatment of fractures.      

硫酸钙人工骨在良性骨肿瘤刮除术后骨缺损填充中的愈合情况及其重建作用研究

目的观察硫酸钙人工骨在良性骨肿瘤刮除术后骨缺损填充中的愈合情况,探讨其在骨肿瘤患者中的重建作用。方法回顾性分析在2010年1月~2013年9月期间,我院骨外科收治的临床随访资料完整的良性骨肿瘤患者,根据植骨材料的不同,分别采用硫酸钙人工骨、同种异体骨以及自体骨修复肿瘤刮除术后骨缺损。每组各选择随机样本40例。根据术后随访的X线结果和相关临床资料。评估不同移植骨在良性骨肿瘤缺损填充中的降解、吸收和愈合情况。结果 120例患者获得3~48个月随访,平均随访时间14.7个月。随访期自体骨组、硫酸钙人工骨组和同种异体骨组均未发生深部感染、植骨不愈合、伤口不愈合、植骨部位骨折及肿瘤复发等相应的并发症,临床获益率达100%。三组病例在骨愈合时间无统计学意义,愈合率也无显著性差异(0.05)。结论用硫酸钙人工骨材料填充良性骨肿瘤刮除后的骨缺损,愈合效果与自体骨和同种异体骨相近。且硫酸钙人工骨生物相容性好,并发症少,值得在临床上推广。     

激素性股骨头坏死与股骨颈骨折患者股骨头内骨小梁形态学对比研究

目的利用微计算机断层扫描技术(Micro-CT)对比分析激素性股骨头坏死与股骨颈骨折患者的股骨头内骨小梁的结构特点。 方法选取2016年9月至2017年9月因股骨颈骨折与激素性股骨头坏死于大连大学附属中山医院行人工全髋关节置换术的患者,分别设为骨折组与坏死组,每组各20例(20髋),术中完整取出股骨头作为研究材料。应用计算机对股骨头进行三维重建,利用x、y、z轴各2个相互平行的平面将股骨头分割成27个区域,27个区域的编号规则：分为内侧、中间、外侧3个区,每组按照由前向后、由上向下的顺序编为1～9号。内侧区编号为m1、m2……m9;中间区编号为c1、c2……c9;外侧区编号为l1、l2……l9。对样本进行Micro-CT断层扫描,获取股骨头样本的计算机三维图像。手工选取兴趣区,采用骨体积分数、骨小梁厚度、骨小梁数量、骨小梁间隙等三维空间参数分别对2组股骨头内骨小梁进行评价。数据比较采用t检验和单因素方差分析。 结果在骨折组中,将股骨头按矢状面分割为内侧区、中间区、外侧区进行对比,中间区表现为骨体积分数均值最大、厚度均值最大、数量均值最大、间隙均值最小的优势骨小梁区域,差异均有统计学意义(F＝36.59、73.50、38.60、48.50,P值均小于0.05);将股骨头按冠状面分割为前区、中间区、后区进行对比,前区表现为骨体积分数均值最大、厚度均值最大、数量均值最大、间隙均值最小,差异均有统计学意义(F＝69.50、43.92、85.40、36.00,P值均小于0.05);将股骨头按水平面分割为上区、中间区、下区进行对比,上区表现为骨体积分数均值最大、厚度均值最大、数量均值最大、间隙均值最小,差异均有统计学意义(F＝37.03、29.47、255.50、45.50,P值均小于0.05)。对比坏死组股骨头不同部位骨小梁微结构参数,如果将股骨头分为内侧区、中间区、外侧区,中间区表现为骨体积分数均值最大、厚度均值最大、数量均值最大、间隙均值最小的优势骨小梁区域,差异均有统计学意义(F＝41.42、26.60、400.00、36.00,P值均小于0.05);如果将股骨头分为上区、中间区、下区,上区表现为骨体积分数均值最大、厚度均值最大、数量均值最大、间隙均值最小,差异均有统计学意义(F＝52.99、25.33、28.50、37.33,P值均小于0.05);如果将股骨头分为前区、中间区、后区,前区表现为骨体积分数均值最大、厚度均值最大、数量均值最大、间隙均值最小,差异均有统计学意义(F＝2 567.17、57.29、42.11、41.17,P值均小于0.05)。与坏死组相比,骨折组骨小梁骨体积分数均值更大,差异有统计学意义(t＝4.90,P＝0.01)、骨小梁厚度均值更大,差异有统计学意义(t＝－4.17,P＝0.01)、骨小梁数量均值更大,差异有统计学意义(t＝－31.37,P＝0.01),骨小梁间隙均值更小,差异有统计学意义(t＝－7.12,P＝0.01)。 结论激素对于坏死股骨头的影响不仅仅是坏死区,包括硬化区、正常骨小梁区,即对于整个股骨头都产生了影响。     

Bone material properties and fracture analysis: Needle insertion for spinal surgery

The effectiveness of percutaneous needle-based therapy and biopsy is demonstrated in a wide variety of medical problems including spinal disorders. Combined with osteoporosis, spinal disorders are increasingly prevalent as our society ages. However, the final position of the needle depends on a complex interplay of material properties of the bone and/or pathology, as well as the shape and material of the needle, and the insertion dynamics. This paper is a survey of the literature in the area of bone material properties and needle/bone interaction in the context of needle placement. It describes research findings on bone material properties and fractures using micro-CT imaging, and integrative imaging. This review paper also discusses the feasibility of using computational methods to predict fracture by simulating needle placement on any patient-specific model with both geometrical and mechanical properties approximating those of the patient’s anatomy.     

骨髓间充质干细胞与同种异体骨复合修复犬下颌骨缺损：成骨能力检测

 背景：同种异体骨与自体骨有相似解剖外形和生物学特性,是较佳的生物支架材料。自体骨髓来源的间充质干细胞具有多分化潜能,能向成骨、成软骨细胞分化,加速骨组织及软骨组织的形成。目的：探讨同种异体骨支架复合自体骨髓间充质干细胞促进犬下颌骨半侧缺损的新骨成骨能力。方法：拔出24只比格犬左侧下颌牙,伤口愈合后2个月,人为造成犬下颌骨缺损,对照组用单纯冻干同种异体骨修复,实验组用同种异体冻干骨加自体骨髓间充质干细胞修复。术后4,12,24周对下颌骨体部进行骨密度扫描以及Micro-CT检查。结果与结论：实验组移植后12周开始,下颌骨的骨密度显著高于对照组(P < 0.05),随着时间推移,实验组和对照组骨密度均增高,但实验组增高明显高于对照组。随时间推移,实验组骨结构参数成阶梯式递增或递减,对照组虽也有递增或递减,但不明显。术后24周实验组感兴趣区骨小梁分离度大于对照组(P < 0.05),骨体积分数、骨小梁数量、骨小梁厚度小于对照组(P < 0.05)。结果表明骨髓间充质干细胞能加速同种异体骨的骨改建速度。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

Rap system of stress stimulation can promote bone union after lower tibial bone fracture: a clinical research

Background Lower tibial bone fracture may easily cause bone delayed union or nonunion because of lacking of dynamic mechanical load.Objective Research Group would design a new instrument as Rap System of Stress Stimulation (RSSS) to provide dynamic mechanical load which would promote lower tibial bone union postoperatively.Methods This clinical research was conducted from January 2008 to December 2010, 92 patients(male 61/female 31, age 16-70years, mean 36.3years) who suffered lower tibial bone closed fracture were given intramedullary nail fixation and randomly averagely separated into experimental group and control group(according to the successively order when patients went for the admission procedure). Then researchers analysed the clinical healing time, full weight bearing time, VAS (Visual Analogue Scales) score and callus growth score of Lane-Sandhu in 3,6,12 months postoperatively. The delayed union and nonunion rates were compared at 6 and 12 months separately.Results All the 92 patients had been followed up (mean 14 months). Clinical bone healing time in experimental group was 88.78±8.80 days but control group was 107.91±9.03days. Full weight bearing time in experimental group was 94.07±9.81 days but control group was 113.24±13.37 days respectively (P<0.05). The delayed union rate in 6 months was 4.3% in experimental group but 10.9% in control group(P<0.05). The nonunion rate in 12 months was 6.5% in experimental group but 19.6% in control group(P<0.05). In 3, 6, 12 months postoperatively, VAS score and Lane-Sandhu score in experimental group had more significantly difference than them in control group.Conclusions RSSS can intermittently provide dynamic mechanical load and stimulate callus formation, promote lower tibial bone union, reduce bone delayed union or nonunion rate. It is an adjuvant therapy for promoting bone union after lower tibial bone fracture.     

Microstructural trabecular bone from patients with osteoporotic hip fracture or osteoarthritis: Its relationship with bone mineral density and bone remodelling markers

Osteoporosis (OP) and osteoarthritis (OA) are the most prevalent musculoskeletal disorders in the elderly but the relationship between them is unclear. The purposes of this study are to analyze the bone turnover markers (BTM), bone mineral density (BMD) and the structural and mechanical properties of trabecular bone in patients with OP and OA, and to explore the relationship between these two diseases. We studied 12 OP patients and 13 OA patients. We analyzed BTM (β-CrossLaps and PINP), BMD and microstructural and biomechanical parameters (micro-CT). Our results were: OP group has higher levels of β-CrossLaps and lower BMD at the femoral neck. Also, OP patients have a decreased volume of trabecular bone and less trabecular number, with architecture showing prevalence of rod-like trabeculae and worse connectivity than OA patients. The biomechanical parameters were worse in OP patients. BMD was correlated with almost all the structural and biomechanical parameters. Moreover, β-CrossLaps was negatively correlated with hip BMD and with bone surface density and positively with trabecular separation. BTM, BMD and bone microstructural changes in osteoporosis are opposite to those of OA. These findings justify a less resistant bone with higher risk of fragility fractures in OP patients. These histomorphometric and biomechanical changes may be suspected by measuring of BMD and β-CrossLaps levels.     

Identification of estrogen-responsive genes involved in breast cancer metastases to the bone

Bone metastasis is the most common metastasis in breast cancer patients. Clinical observations propose strong association between estrogen receptor (ER)-positive tumors and the development of bone metastases. We hypothesized of biologically diverse sets of hormone-dependent tumors predisposed to bone metastases and of possible role of ER-signaling pathways in the development and progression of bone metastases. We developed a novel in vitro estrogen (E2)-responsive model system, in which breast cancer cells and bone cells express high levels of either ERα or ERβ. Using co-culture approach and gene array technology we identified E2-responsive genes involved in the interaction between cancer cells and bone cells. We detected 13 genes that were altered solely by ERα and 11 genes that were regulated solely by ERβ in cancer cells. Only 5 genes were modified by both ERα and ERβ. Interestingly, the majority of genes in bone cells were altered through ERβ. Two genes, namely MacMarcks and Muc-1, whose changes in expressions in cancer cells in response to E2 were highly significant, were selected for immunohistochemical analysis using tissue microarrays of 59 infiltrating ductal carcinomas. Our results indicated that both MacMarcks and Muc-1 were expressed at high frequency in ER-positive tumors. The correlation between ERα- and ERβ-status of hormone-dependent tumors with combined expression of these two markers might suggest a more aggressive tumor phenotype associated with bone metastases. Further analysis of tissues with clinicopathological characteristics and known bone metastatic disease will indicate potential prognostic values of these and other markers in the development of bone metastases in a subgroup of “bad” hormone-dependent breast cancer. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

四肢长骨转移瘤诊断和外科治疗分析

目的 探讨四肢长骨转移瘤的诊断技巧、外科治疗方法及临床意义。方法 回顾性分析西安交通大学医学院附属红会医院骨病肿瘤科2012年1月—2017年1月治疗的54例四肢长骨转移瘤患者的临床资料,其中男29例、女25例,年龄48~72(60.6±12.5)岁;股骨38例(70.4%),肱骨16例(29.6%)。54例长骨转移瘤患者均行X线、CT、MRI及全身骨扫描检查,19例进行组织活检。术前Tokuhashi评分≥12分者31例、9~11分者8例、≤8分者15例,术前Mirls评分为9~11分,平均10.3分;依据Tokuhashi评分及骨转移瘤部位拟定治疗方案,按照Mirls评分对濒临骨折患者的治疗决策进行评估。采用VAS于术前及术后3个月对患者疼痛进行评估、Karofsky体能状况评分(KPS) 评估患者术前及术后3个月身体状况、骨与软组织肿瘤协会(MSTS)评分评价患者术后肢体功能情况,应用Kaplan-Meier法进行生存分析。结果 35例(64.8%)患者通过病史资料和影像学评估获得长骨转移瘤的诊断,其与术后病理诊断结果一致;19(35.2%)例通过病史资料、影像学评估和组织活检(15例芯针经皮穿刺活检+4例切开组织活检)获得长骨转移瘤诊断。54例患者术后随访4~36个月,平均18个月。随访期间病死31例,术后平均存活10.5(4.5~30)个月;存活23例。Kaplan-Meier法生存分析显示,6个月生存率70.4%(38/54),1年生存率57.4%(31/54),2年生存率46.2%(25/54)。围手术期内患者未出现并发症,随访期间手术部位未发生内植物失效、病理性骨折等并发症。术后3个月疼痛VAS与术前比较,差异有统计学意义(t=4.085, P＜0.01);术后3个月患者KPS明显改善,与术前比较差异有统计学意义(χ²=21.476, P＜0.01)。MSTS功能评分:术后3个月平均21.95(16~28)分,上肢平均20.54分、下肢平均23.36分;其中优24.07%(13/54)、良53.70%(29/54)、中20.37%(11/54)、差1.85%(1/54),优良率77.78%(42/54)。结论 病史资料评估结合详细的影像学分析可以对大部分四肢长骨转移瘤做出正确诊断;对于难以确诊的病例,需进行组织活检。恰当的外科治疗能够有效地缓解长骨转移瘤患者的疼痛,提高患者的生活质量。     

Novel murine mammary epithelial cell lines that form osteolytic bone metastases: effect of strain background on tumor homing

We have developed a series of novel mammary epithelial cell lines from tumors arising in strain 129 mice, with the ultimate goal of evaluating the role of host factors in the development of bone metastases. Mammary tumors were induced in mice with subcutaneously implanted medroxyprogesterone acetate (MPA) pellets followed by administration of DMBA by oral gavage. Mammary tumor development was efficient in the 129 strain and was independent of osteopontin (OPN) expression. Epithelial cell lines were isolated from these tumors; surprisingly, these cells did not form tumors upon inoculation into the mammary fat pad of syngeneic mice, even when MPA was present. One OPN-deficient cell line was selected for further study; full transformation of these cells required expression of both polyoma middle T and activated ras. These doubly transfected cells, 1029 GP+Er3, grew in soft agar, and formed hormone-independent tumors efficiently in the mammary fat pad that spontaneously metastasized to several soft tissue sites but not to the bone. Derivatives of these cells were isolated from tumors arising in the fat pad and from a lung metastasis (r3T and r3L, respectively): these cells formed tumors more rapidly in the fat pad than the parental GP+Er3 cells. Upon left ventricle injection, the r3T and r3L cells formed osteolytic bone metastases in 129 mice, with few metastases seen in other organs. These tumors filled the marrow cavity, and caused extensive destruction of both cortical and trabecular bone. Intriguingly, in an alternative syngeneic host, (129× C57Bl/6) F1, osteolytic bone metastases were not seen on x-ray; instead extensive liver metastasis was present in these mice, indicating that genetic factors in these two strains regulate tumor cell homing and distribution during metastasis. These cell lines provide an important new tool in the study of bone metastasis, particularly in elucidating the role of host factors in the development of these lesions, as the 129 mouse strain is frequently used for genetic manipulations in the mouse. This revised version was published online in July 2006 with corrections to the Cover Date.     

骨水泥、钉道植骨强化动力髋螺钉固定修复老年骨质疏松性股骨转子间骨折

背景：对于老年骨质疏松性髋部骨折的动力髋螺钉固定,如能避免使用过程中造成的骨量丢失,或是采用其他手段增加固定螺钉把持力,将改善动力髋螺钉固定的治疗效果。 目的：对比研究3种固定方式修复老年骨质疏松性股骨转子间骨折的效果。   方法：回顾性分析近5年来采用常规动力髋螺钉内固定、骨水泥强化后动力髋螺钉固定及主钉道压配植骨配合动力髋螺钉固定3种固定方式治疗老年骨质疏松性股骨转子间骨折患者的资料,分别设为对照组、骨水泥组和植骨组。 结果与结论：经固定后2年随访,植骨组、骨水泥组和对照组Harris髋关节功能评分优良率分别为95%,80%,70%。植骨组骨折临床愈合时间明显缩短(P < 0.05),出现螺钉固定失败情况与骨水泥组相当。对照组较其他2组相对更多出现退钉等内固定失败情况。结果表明,与其他常规动力髋螺钉内固定、骨水泥强化后动力髋螺钉固定方式相比较,主钉道压配植骨配合动力髋螺钉内固定的疗效及安全性更好。中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程     

硼酸盐生物玻璃和自体髂骨移植对新西兰兔桡骨大段骨缺损修复的对比研究

目的比较硼酸盐生物玻璃和自体髂骨移植对新西兰兔桡骨大段骨缺损的修复效果。方法取38只新西兰兔,制作桡骨干15 mm骨缺损动物模型,并将其随机分为空白组(8只)、对照组(15只)和实验组(15只),对照组和实验组分别植入自体髂骨和硼酸盐生物玻璃(borate glass, BG)。术后4、8和12周行X线检查,观察材料的降解和新生骨生成情况。术后6周和9周分别腹腔注射茜素红和钙黄绿素。术后12周取材行组织学和Micro-CT检查。结果影像学和组织学结果显示对照组和实验组新骨生成明显优于空白组,12周后对照组和实验组新骨完全修复缺损;实验组材料降解与新骨生成协调进行;术后12周缺损处组织学切片显示,对照组和实验组缺损处有大量的新生骨组织。结论硼酸盐生物玻璃可完全修复兔桡骨干大段骨缺损,其修复效果与自体髂骨移植接近,在骨组织工程领域有广阔的应用前景。     

Breast cancer metastasis to bone: evaluation of bioluminescent imaging and microSPECT/CT for detecting bone metastasis in immunodeficient mice

This study sought to determine if weekly X-ray exposure affected breast cancer cell metastasis to bone and to also evaluate the use of bioluminescent imaging (BLI) and microSPECT for detection of metastatic bone lesions. Five week old nude mice were randomly assigned to the CT exposed (n = 7) and no CT exposure (n = 6) treatment groups. Mice received an intracardiac injection of MDA-MB-435 human breast cancer cells transduced with luciferase, or a sham injection (saline). The CT exposed group of mice received CT irradiation once a week for 5 weeks. All mice underwent weekly BLI and select mice received Tc-99m-MDP followed by microSPECT imaging after 5 weeks. Pathological evaluation and histomorphometry were used to assess the affect of CT X-rays on bone metastasis and to evaluate BLI. BLI results found no significant difference in metastasis between animals that received CT and those that did not (P > 0.05); however, histomorphometry of the knee joints revealed a significant increase (P = 0.029) in tumor area of the leg bones in mice that received CT exposure (60% ± 7%) compared to animals that did not receive CT scans (33% ± 8%). Compared to histological analysis, BLI of the leg and spine was determined to have excellent sensitivity (100%), good specificity (80–90%) and accuracy (90–96%), a positive predictive value of 81–93% and a 100% negative predictive value. Thus, multi-modality imaging techniques can be very useful for monitoring bone metastasis, however microCT X-rays should be used judiciously in order to limit irradiation that may stimulate increased metastasis to specific regions of the skeleton. MicroSPECT imaging did not detect metastatic lesions in the legs of these young nude mice.     

Micro-CT-based screening of biomechanical and structural properties of bone tissue engineering scaffolds

The development of successful scaffolds for bone tissue engineering requires a concurrent engineering approach that combines different research fields. In order to limit in vivo experiments and reduce trial and error research, a scaffold screening technique has been developed. In this protocol seven structural and three biomechanical properties of potential scaffold materials are quantified and compared to the desired values. The property assessment is done on computer models of the scaffolds, and these models are based on micro-CT images. As a proof of principle, three porous scaffolds were evaluated with this protocol: stainless steel, hydroxyapatite, and titanium. These examples demonstrate that the modelling technique is able to quantify important scaffold properties. Thus, a powerful technique for automated screening of bone tissue engineering scaffolds has been developed that in a later stage may be used to tailor the scaffold properties to specific requirements.